EVALUATION KIT AVAILABLE MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic General Description Features The MAX13325/MAX13326 dual audio line drivers provide a reliable differential interface between automotive audio components. The devices feature differential inputs and outputs, integrated output diagnostics, and are controlled using an I2C interface or operate in stand-alone mode. The outputs can deliver up to 4VRMS into 100I loads. S Comprehensive Programmability and Diagnostics Using I2C Interface The MAX13325 buffers analog audio signals for transmission over long cable distances with a fixed gain of 12dB, whereas the MAX13326 provides a 0dB fixed gain. The diagnostics on the outputs report conditions on a per channel basis, including short to GND, short to battery, overcurrent, overtemperature, and excessive offset. The output amplifiers can drive capacitive loads up to 4nF to ground and 3nF differentially. The outputs are protected according to IEC 61000-4-2 Q8kV Contact Discharge, and Q15kV Air Gap. The MAX13325/MAX13326 are specified from -40NC to +105NC and are available in a 28-pin TSSOP package with an exposed pad. Applications Automotive Radio and Rear Seat Entertainment S Autoretry Function in Stand-Alone Mode S Drive Capacitive Loads 3nF Differentially, 4nF to Ground S 112dB Signal-to-Noise Ratio S Low 0.002% THD at 4VRMS into 2.7kI Loads S High PSRR (70dB at 1kHz) S High CMRR (80dB at 1kHz) S Low Output Noise (3VRMS), MAX13326 S Excellent Channel-to-Channel Matching S Load-Dump Transient Protection S Protected Output Against Various Short-Circuit Conditions S ESD Protection for 8kV Contact Discharge, 15kV Air Gap S Long-Distance Drive Capability Typically Up to 15m or Greater S Noise-Rejecting Differential Inputs and Outputs S Low-Power Shutdown Mode < 10A Professional Remote Audio Amplifiers S Hardware or Software MUTE Function S 28-Pin TSSOP Package with Exposed Pad Typical Operating Circuit Ordering Information VSUP C1 470nF +5V VL C6 100nF CP CM D2** +12V * OPTIONAL C2 1 F R1 1kI Q1 CHOLD D1 ADD1 CHARGE PUMP SDA FLAG TO MICROPROCESSOR AND DIGITAL CONTROL BIAS MUTE FROM AUDIO SOURCE C3 1F PGND I2C INTERFACE SHDN C7 2.2F BIAS C4 10F CSS C5 220nF OUTLP INLP OUTPUT DIAGNOSTIC ESD PROTECTION -40NC to +105NC 12 MAX13326GUI/V+ 28 TSSOP-EP* -40NC to +105NC 0 1nF 1nF OUTRP INRP RIGHT C10 2.2F MAX13325GUI/V+ 28 TSSOP-EP* 1nF OUTLM INLM C8 2.2F FROM AUDIO SOURCE GAIN (dB) /V denotes an automotive qualified part. +Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad. GND LEFT C9 2.2F PINPACKAGE VDD ADD0 SCL TEMP RANGE PART 1nF 1nF OUTRM INRM MAX13325 MAX13326 1nF *OPTIONAL : NEEDED FOR AUTOMOTIVE LOAD DUMP PROTECTION ONLY **USE D2 WHEN CHARGE PUMP IS OFF AND EXTERNAL SUPPLY IS PROVIDED TO C HOLD For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maximintegrated.com. 19-5136; Rev 5; 4/13 MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic ABSOLUTE MAXIMUM RATINGS VDD to PGND.........................................................-0.3V to +28V CHOLD ..................................................................-0.3V to +28V VL to GND................................................................-0.3V to +6V GND, PGND .........................................................-0.3V to +0.3V OUT_ to PGND......................................................... -0.3V to 28V IN_, BIAS to AGND...................................-0.3V to (VDD + 0.3V) SCL, SDA, ADD0, ADD1, MUTE, SHDN, FLAG to GND...........................................................-0.3V to +6V OUT_ Short Circuit to PGND or VDD..........................Continuous Short Circuits Between Any OUT_.............................Continuous Continuous Power Dissipation (TA = +70NC) (multilayer board) 28-Pin TSSOP (derate 27mW/NC above +70NC)......2162.2mW Operating Temperature Range......................... -40NC to +105NC Storage Temperature Range............................. -65NC to +150NC Junction Temperature......................................................+150NC Lead Temperature (soldering, 10s).................................+300NC Soldering Temperature (reflow).......................................+260NC Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. PACKAGE THERMAL CHARACTERISTICS (Note 1) Junction-to-Ambient Thermal Resistance (qJA)...........37C/W Junction-to-Case Thermal Resistance (qJC)..................2C/W Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial. ELECTRICAL CHARACTERISTICS (VDD = 14.4V, VL = 5V, RL = J, load impedance from OUT_+ to OUT_-, TA = TJ = -40NC to +105NC, typical values are TA = +25NC, unless otherwise noted.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 50 V AMPLIFIER DC CHARACTERISTICS Transient Supply Voltage (Load Dump) Operating Supply Voltage Range VDDMAX Using external nMOS-RTR020N05, 300ms duration VDD 4.5 18 VL 2.7 5.5 V VDD OVLO Threshold VDDOV Rising edge 18.5 19.2 V VDD UVLO Threshold VDDUV Falling edge 3.3 3.5 V VLUV Falling edge 2.2 2.4 V VL UVLO Threshold Supply Current Logic Supply Current Shutdown Supply Current IDD IL ISHDN TA = +25NC, no load 39 TA = -40NC to +105NC, no load VL = 5V IDD 1.7 TA = +25NC 0.5 TA = -40NC to +105NC 0.5 < 0.1 IL Turn-On Time (from Shutdown) SHDN = VL, CCSS = 220nF RINDIF Single-Ended Input Impedance RIN Signal-Path Gain (Note 3) AV 2 mA mA 10 2 220 MUTE = VL Turn-On Time (from Mute) Differential Input Resistance mA 50 FA FA ms 6 ms Measure across input 18 24 30 Each input to ground (MAX13325) 15 20 25 Each input to ground (MAX13326) 12 16 20 MAX13325 11.8 12 12.2 MAX13326 -0.2 0 +0.2 kI kI dB Maxim Integrated MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic ELECTRICAL CHARACTERISTICS (continued) (VDD = 14.4V, VL = 5V, RL = J, load impedance from OUT_+ to OUT_-, TA = TJ = -40NC to +105NC, typical values are TA = +25NC, unless otherwise noted.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP Channel-to-Channel Gain Tracking Differential Mode Output Balance OUT_+ to OUT_- (Note 4) MAX UNITS Q0.4 dB -40 MUTE = GND, TA = +25NC Q0.5 Q10 MUTE = VL, TA = +25NC Q0.2 Q3 50 52.5 % 92 115 kI Output Offset Voltage (OUT_+ to OUT_-) VOOS BIAS Voltage VBIAS Relative to VDD BIAS Impedance ZBIAS IBIAS = Q10FA Output-Voltage Swing Differential 69 VDD = 14.4V, VIN = Q14.4V, RL = 1kI Q12.5 VDD = 5.0V, VIN = Q5V, RL = 1kI Q4.2 VDD = 4.5V to 18V Power-Supply Rejection Ratio PSRR Common-Mode Rejection Ratio CMRR dB -80 V -96 VDD = 14.5V, +500mVP-P ripple at 1kHz -95 VDD = 14.5V, +500mVP-P ripple at 10kHz -80 VIN = 1VRMS, 100Hz to 10kHz -48 mV dB -80 dB AMPLIFIER AC CHARACTERISTICS Total Harmonic Distortion Plus Noise (Note 5) Total Harmonic Distortion Plus Noise at VDD = 5V (Note 5) THD+N THD+N VOUT = 4VRMS, RL = 2.7kI 0.002 VOUT = 4VRMS, RL = 1kI 0.004 VOUT = 4VRMS, RL = 100I, VDD = 8V 0.03 VOUT = 7VRMS, RL = 1kI 0.2 VOUT = 1VRMS, RL = 2.7kI 0.01 VOUT = 1VRMS, RL = 1kI 0.02 VOUT = 2VRMS, RL = 1kI 0.8 Capacitive-Load Stability % 3 No sustained oscillation Capacitive-Load Drive Capability Signal-to-Noise Ratio (Note 5) % SNR CLOAD to GND 4 CLOAD differential 3 MAX13325, gain = 12dB, VOUT = 4VRMS, A-weighted 112 MAX13326, gain = 0dB, VOUT = 4VRMS, A-weighted 122 Unity-Gain Bandwidth Output Slew Rate Output-Voltage Noise 3 MHz 2.5 V/Fs A-weighted, MAX13325 10 3 VIN = 1VRMS, 1kHz Mute Time To achieve soft mute, CCSS = 220nF nF dB A-weighted, MAX13326 Crosstalk nF FV -110 dB 4 ms VIN = 1VRMS, 1kHz -75 dB Click-and-Pop Level (Note 6) KCP Into and out of mute -70 dBV Click-and-Pop Level (Note 6) KCP Into and out of shutdown, 1kI -45 dBV Mute Attenuation Maxim Integrated 3 MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic ELECTRICAL CHARACTERISTICS (continued) (VDD = 14.4V, VL = 5V, RL = J, load impedance from OUT_+ to OUT_-, TA = TJ = -40NC to +105NC, typical values are TA = +25NC, unless otherwise noted.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP VDD = 4.5V, ISOURCE = 6.6mA 3.2 4.0 VDD = 18V, ISOURCE = 6.6mA 4.5 MAX UNITS CHARGE PUMP Charge-Pump Overdrive Voltage, VCHOLD - VDD (Hard Mode) VCPH VCHOLD - VDD (Soft Mode) VCPS VDD unconnected, ISOURCE = 40FA, VL = 3.3V 2.1 VL = 5V Charge-Pump Frequency fCP CPOFF = 0 5.5 V V 3.9 CPF[1:0] = 00 333 CPF[1:0] = 01 190 CPF[1:0] = 10 426 CPF[1:0] = 11 260 kHz DIAGNOSTICS Output Current Limit Short to GND or battery 580 mA 230 mA Q250 mV Thermal Warning Threshold 135 NC Thermal Shutdown Threshold 165 NC Thermal Shutdown Hysteresis 15 NC Current-Limit Warning Threshold Open-Load Detection Output Offset Detection 10 Valid when muted kI ESD PROTECTION Air Gap IEC 61000-4-2 OUT_ pins Q15 kV Contact Discharge IEC 61000-4-2 OUT_ pins Q8 kV HBM All pins Q2 kV 4 Maxim Integrated MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic DIGITAL CHARACTERISTICS (VDD = 14.4V, VL = 3.3V, TA = TJ = -40NC to +105NC, typical values are TA = +25NC, unless otherwise noted.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DIGITAL INTERFACE Input-Voltage High VINH VL = 2.7V to 5.5V Input-Voltage Low VINL VL = 2.7V to 5.5V 0.75 x VL V 0.25 x VL Input-Voltage Hysteresis 50 Input Leakage Current V mV Q100 FA Output Low Voltage FLAG, SDA, ISINK = 3mA 0.4 Output Leakage Current FLAG, SDA = 5.5V V 2 FA Stand-Alone FLAG Pulse Width ADD0, ADD1 = GND 100 ms Stand-Alone Fault Retry Time ADD0, ADD1 = GND 500 ms I2C TIMING Serial-Clock Frequency fSCL Bus Free Time tBUF 0 Between START and STOP conditions 400 1.3 Fs 0.6 Fs tLOW 1.3 Fs SCL High Time tHIGH 0.6 Data Hold Time tHD:DAT 0 Data Setup Time tSU:DAT 100 Hold Time SCL Low Time tHD:STA Repeated START condition kHz Fs 900 ns ns Bus Capacitance CB Per bus line 400 pF Receiving Rise Time tR SCL, SDA 20 + 0.1CB 300 ns Receiving Fall Time tF SCL, SDA 20 + 0.1CB 300 ns Transmitting Fall Time tF SDA, VL = 3.6V 20 + 0.05CB 250 ns STOP Condition Setup Time Pulse Width of Suppressed Spike tSU:STO 0.6 tSP 0 Fs 50 ns Note 2: All devices are 100% tested at TA = +25NC. Limits over temperature are guaranteed by design. (VOUT_ + ) - (VOUT_ - ) Note 3: Signal path gain is defined as: 20 x log . (VIN_ + ) - (VIN _ - ) Note 3: Signal Path Gain is defined as Note 4: Measured in differential output mode, differential input voltage 4VP-P (for 0dB gain), 1VP-P (for 12dB gain) 1kHz. Common-mode output balance is defined as: 20 x log . ) x 2 ( | VOUT_ + ) - ( VOUT_ - ) ( VOUT_ + ) + ( VOUT _- Common-Mode Output Balance is defined as Note 5: 22Hz to 22kHz measurement bandwidth. Note 6: KCP level is calculated as 20log[(peak voltage during mode transition, no input signal)/1VRMS]. Units are expressed in dBV. Maxim Integrated 5 MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic Typical Operating Characteristics (VDD = 14.4V, VL = 5V, RL = 1kI, gain = 12dB, TA = +25NC, unless otherwise noted.) 0.15 0.10 0.006 -60 0.004 -70 0.003 0.002 -90 0.001 0 -100 5 20 35 50 65 80 95 0 -10 MAX13325 toc04 0.008 0.006 -60 -70 -80 0.002 0 -120 0.004 1 2 3 4 5 6 7 8 9 500mVP-P RIPPLE -40 -50 -90 -100 -110 100 10 10 MUTE ATTENUATION vs. FREQUENCY -76 RIGHT CHANNEL -80 100 1k FREQUENCY (Hz) 10k 100k 100k 10k MAX13325 toc03 100k RIGHT TO LEFT LEFT TO RIGHT 10 100 1k 10k 100k FREQUENCY (Hz) FFT vs. FREQUENCY MAX13325 toc08 0 VOUT = 1VRMS 1kHz -15 -30 -45 FFT (dBV) LEFT CHANNEL -72 OUTPUT-NOISE VOLTAGE (dBV) -68 0 -10 -20 -30 -40 -50 -60 -70 -80 90 -100 -110 -120 -130 -140 -150 1k 1VRMS INPUT 20kHz AES17 FILTER OUTPUT-NOISE VOLTAGE vs. FREQUENCY MAX13325 toc07 2VRMS INPUT A-WEIGHTED 10k 0 -10 -20 -30 -40 -50 -60 -70 -80 -90 -100 -110 -120 -130 -140 FREQUENCY (Hz) OUTPUT VOLTAGE (VRMS) -60 1k 100 CROSSTALK vs. FREQUENCY CROSSTALK (dB) 0.010 RIGHT CHANNEL 10 FREQUENCY (Hz) -20 -30 PSRR (dB) 0.012 10 100k POWER-SUPPLY REJECTION RATIO vs. FREQUENCY 0.014 -64 10k TOTAL HARMONIC DISTORTION PLUS NOISE vs. OUTPUT VOLTAGE 0.016 0 1k FREQUENCY (Hz) fIN = 1kHz LEFT CHANNEL 0 100 10 TEMPERATURE (C) 0.018 MUTE ATTENUATION (dB) 0.005 -80 0.020 THD+N (%) 0.007 -40 0.05 -40 -25 -10 6 0.008 -30 -50 1VRMS OUTPUT 0.009 THDN (%) 0.20 0.010 MAX13325 toc06 -20 CMRR (dB) 0.25 1VRMS INPUT 20kHz AES17 FILTER -10 MAX13325 toc05 SHUTDOWN CURRENT (A) 0.30 0 MAX13325 toc02 NO LOAD INPUTS SHORTED VSHDN = 0V MAX13325 toc01 0.40 0.35 TOTAL HARMONIC DISTORTION PLUS NOISE vs. FREQUENCY COMMON-MODE REJECTION RATIO vs. FREQUENCY MAX13325 toc09 SHUTDOWN CURRENT vs. TEMPERATURE -60 -75 -90 -105 -120 -135 -150 0 2 4 6 8 10 12 14 16 18 20 FREQUENCY (kHz) 10 100 1k 10k 100k FREQUENCY (Hz) Maxim Integrated MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic Typical Operating Characteristics (continued) (VDD = 14.4V, VL = 5V, RL = 1kI, gain = 12dB, TA = +25NC, unless otherwise noted.) OUTPUT VOLTAGE vs. CHARGE-PUMP OVERDRIVE VOLTAGE LEFT CHANNEL -0.005 -0.010 8.5 THDN = 1% fIN = 1kHz VDD = 14.4 RL = 1kI CPOFF = 1 8.0 7.5 -0.015 RIGHT CHANNEL -0.020 -40 -25 -10 5 7.0 20 35 50 65 80 95 0 TEMPERATURE (C) 0.15 MAX13326 (0dB) VOUT = 1VRMS LEFT CHANNEL 0.05 0 RIGHT CHANNEL -0.10 -0.15 -0.20 2 4 Maxim Integrated 6 8 10 12 14 16 18 20 FREQUENCY (kHz) -40 -25 -10 5 20 35 50 65 80 TEMPERATURE (C) MAX13325 toc12 1k 10k 100k GAIN ERROR vs. FREQUENCY 0.10 -0.05 0 100 FREQUENCY (Hz) GAIN vs. TEMPERATURE GAIN (dB) MAX13326 (0dB) 1VRMS OUTPUT 10 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 0.20 MAX13325 toc13 0 -10 -20 -30 -40 -50 -60 -70 -80 -90 -100 -110 -120 -130 -140 -150 0.050 0.045 0.040 0.035 0.030 0.025 0.020 0.015 0.010 0.005 0 -0.005 -0.010 -0.015 -0.020 -0.025 -0.030 -0.035 -0.040 -0.045 -0.050 (VCHOLD - VDD) (V) OUTPUT-NOISE VOLTAGE vs. FREQUENCY OUTPUT NOISE VOLTAGE (dBV) MAX13325 toc12 9.0 95 GAIN ERROR (dB) 0 9.5 GAIN ERROR (dB) 0.005 GAIN ERROR vs. FREQUENCY MAX13325 toc14 0.010 10.0 OUTPUT VOLTAGE (V) 0.015 GAIN ERROR (dB) 10.5 MAX13325 toc10 0.020 0.050 0.045 0.040 0.035 0.030 0.025 0.020 0.015 0.010 0.005 0 -0.005 -0.010 -0.015 -0.020 -0.025 -0.030 -0.035 -0.040 -0.045 -0.050 MAX13326 (0dB) 1VRMS OUTPUT 10 100 1k 10k FREQUENCY (Hz) MAX13325 toc15 GAIN ERROR vs. TEMPERATURE 100k 7 MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic Pin Configuration TOP VIEW + BIAS 1 VL 2 27 FLAG I.C. 3 26 CM I.C. 4 25 CP INLP 5 INLM 6 VDD 7 22 CHOLD INRM 8 21 PGND INRP 28 CSS 24 OUTLP MAX13325 MAX13326 23 OUTLM 9 20 OUTRP I.C. 10 19 OUTRM I.C. 11 18 GND SHDN 12 17 ADD1 MUTE 13 16 SDA ADD0 14 EP 15 SCL TSSOP CONNECT TO PGND. Pin Description PIN NAME 1 BIAS 2 VL Logic Supply Voltage. Connect VL to a 2.7V to 5V logic supply. Bypass VL to GND with a 0.1FF capacitor. 3, 4, 10, 11 I.C. Internally Connected. Leave unconnected. 5 INLP Left Audio Positive Input. Either input of each pair can be used as a single-ended input, with the complementary input bypassed to GND. 6 INLM Left Audio Negative Input. Either input of each pair can be used as a single-ended input, with the complementary input bypassed to GND. 7 VDD Power-Supply Input. Connect VDD to the supply voltage. Bypass VDD to GND through a 1FF capacitor. 8 INRM Right Audio Negative Input. Either input of each pair can be used as a single-ended input, with the complementary input bypassed to GND. 9 INRP Right Audio Positive Input. Either input of each pair can be used as a single-ended input, with the complementary input bypassed to GND. 12 SHDN Shutdown Input. Drive SHDN low to power down the device. 13 MUTE Mute Input. Drive MUTE low to mute the outputs. The outputs are low impedance in mute. 8 FUNCTION Analog Bias Voltage. Bypass BIAS to GND with a 10FF capacitor. Maxim Integrated MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic Pin Description (continued) PIN NAME 14 ADD0 FUNCTION I2C Address Inputs. Connect ADD0 and ADD1 to VL, GND, SCL, or SDA to select 7 I2C addresses. Connect ADD0 and ADD1 to GND for stand-alone mode. 15 SCL Serial Clock 16 SDA Serial-Data IO 17 ADD1 I2C Address Inputs. Connect ADD0 and ADD1 to VL, GND, SCL, or SDA to select 7 I2C addresses. Connect ADD0 and ADD1 to GND for stand-alone mode. 18 GND Analog Ground. Ground connection for the input bias and gain circuits. 19 OUTRM Right Audio Negative Output. Each output is current limited. 20 OUTRP Right Audio Positive Output . Each output is current limited. 21 PGND Power Ground. Ground connection for the output stage drivers. 22 CHOLD Charge-Pump Output (When Charge Pump is On; CPOFF = 0). When the charge pump is off, provide an external supply through a diode to the CHOLD input. Bypass CHOLD with 1F to PGND. 23 OUTLM Left Audio Negative Output. Each output is current limited. 24 OUTLP Left Audio Positive Outputs. Each output is current limited. 25 CP Charge-Pump Flying Capacitor, Positive Connection 26 CM Charge-Pump Flying Capacitor, Negative Connection 27 FLAG 28 CSS -- EP Open-Drain Fault Flag Output. FLAG indicates a fault on any one channel. In stand-alone mode, FLAG is stretched to a typical pulse width of 100ms. Soft-Start Capacitor Connection. CSS is charged/discharged by < 100FA current to get soft mute/ play transition. Bypass to GND through a 220nF capacitor. Exposed Pad. Connect to PGND. Detailed Description The MAX13325/MAX13326 audio line drivers are designed to transmit audio data across noisy environments. The differential interface is highly resistant to noise injection from external sources common to automotive applications. The MAX13325/MAX13326 operate in stand-alone or I2C-compatible mode with diagnostic outputs capable of detecting short to GND or battery, overcurrent, overtemperature, or excessive offset. A short across another audio output signal line is also protected. Table 1. Register Address Map ADDRESS REGISTER TYPE NAME READ/WRITE DEFAULT 0x00 Configuration CONFIG Read/Write 0x00 0x01 Command Byte CMD Read/Write 0x00 0x02 General Fault GFAULT Read 0x00 0x03 Left-Channel Fault LFAULT Cleared on Read 0x00 0x04 Right-Channel Fault RFAULT Cleared on Read 0x00 0x05 Flag FLAG Read 0x04 (12dB) 0x05 (0dB) 0x06 General Mask GMASK Read/Write 0x00 0x07 Left-Channel Mask LMASK Read/Write 0x00 0x08 Right-Channel Mask RMASK Read/Write 0x00 Maxim Integrated 9 MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic Configuration Register Table 2. Configuration Register Format REGISTER DATA FUNCTION ADDRESS CODE (HEX) D7 D6 D5 D4 D3 D2 D1 D0 POR STATE (HEX) Configuration Register 0x00 DIAG ENABLE MUTE CPOFF OLDL OLDR CPF1 CPF0 0x00 DIAG: Set DIAG to 1 to enable diagnostic mode. Write '0' to disable diagnostic mode. ENABLE: Set ENABLE bit to 1 to enable the device. Write `0' disables the device. Low on the SHDN pin overrides the ENABLE bit. MUTE: Set the MUTE bit to 1 to mute both the output channels. Output is low impedance when in mute. Low on the MUTE pin input overrides the MUTE bit. CPOFF: Set the CPOFF bit to 1 to turn off the charge pump. CHOLD pin must be externally supplied (see the VCPH parameter in the Electrical Characteristics table). Charge pump is enabled when CPOFF = 0. OLDL: Write 1 to the OLDL bit to initiate the open-load detection for the left channel. To run OLDL again, write `0' and `1' again. OLDR: Write 1 to the OLDR bit to initiate the open-load detection for the right channel. To run OLDR again, write `0' and `1' again. Table 2a. Charge-Pump Frequency Bits CPF1 CPF0 FREQUENCY (kHz) 0 0 333 0 1 190 1 0 426 1 1 260 CPF[1:0]: Sets the frequency of the charge pump. Command Byte Register Table 3. Command Byte Register Format REGISTER DATA FUNCTION ADDRESS CODE (HEX) D7 D6 D5 D4 D3 D2 D1 D0 POR STATE (HEX) Command Byte Register 0x01 RETRYL RETRYR x x x x x x 0x00 RETRYR: The right-channel power amplifier switches off after a fault condition. Write `1' to turn it back on after the fault condition. RETRYL: The left-channel power amplifier switches off after a fault condition. Write `1' to turn on the left-channel power amplifier after the fault condition. 10 Maxim Integrated MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic General Faults Table 4. General Fault Register Format REGISTER DATA FUNCTION ADDRESS CODE (HEX) D7 D6 D5 D4 D3 D2 D1 D0 POR STATE (HEX) General Fault Register 0x02 x TWARN TSHDN DUMP x x x x 0x00 TWARN: The TWARN bit is set to `1' when the temperature warning threshold is reached. TSHDN: The TSHDN is set to `1' when the temperature shutdown threshold is reached. DUMP: The DUMP bit is set to `1' when the VDD voltage exceeds the overvoltage threshold. Set the appropriate mask bit in the GMASK register to detect the general faults. See Table 8. Left-Channel Faults Table 5. Left-Channel Fault Register Format FUNCTION ADDRESS CODE (HEX) Left-Channel Fault Register 0x03 REGISTER DATA D7 D6 D5 D4 D3 D2 D1 D0 POR STATE (HEX) SVDDL SGNDL LIMITL x OFFSETL OPENL x x 0x00 SVDDL: The SVDDL bit is set to `1' when a short to VDD is detected on the left channel. SGNDL: The SGNDL bit is set to `1' when a short to GND is detected on the left channel. LIMITL: The LIMITL bit is set to `1' when the current-limit threshold is tripped for left output. OFFSETL: The OFFSETL bit is set to `1' when excessive offset is detected on the left-channel output. OPENL: The OPENL bit is set to `1' when an open load is detected on the left channel. Set the appropriate mask bit in the LMASK register to detect the faults on the left channel. See Table 9. When any bit of the LFAULT register is high, the FLAG output is low. Right-Channel Faults Table 6. Right-Channel Fault Register Format FUNCTION ADDRESS CODE (HEX) Right-Channel Fault Register 0x04 REGISTER DATA D7 D6 D5 D4 D3 D2 D1 D0 POR STATE (HEX) SVDDR SGNDR LIMITR x OFFSETR OPENR x x 0x00 SVDDR: The SVDDR bit is set to `1' when a short to VDD is detected on the right channel. SGNDR: The SGNDR bit is set to `1' when a short to GND is detected on the right channel. LIMITR: The LIMITR bit is set to `1' when the current-limit threshold is tripped for right output. OFFSETR: The OFFSETR bit is set to `1' when excessive offset is detected on the right-channel output. OPENR: The OPENR bit is set to `1' when an open load is detected on the right channel. Set the appropriate mask bit in the RMASK register to detect the faults on the right channel. See Table 10. When any bit of the RFAULT register is high, the FLAG output is pulled low. Maxim Integrated 11 MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic FLAG Register Table 7. Flag Register Format FUNCTION ADDRESS CODE (HEX) FLAG Register 0x05 REGISTER DATA D7 D6 D5 D4 D3 D2 D1 D0 POR STATE (HEX) FLAG LHIGHZ RHIGHZ OFFSETL OFFSETR ID2 ID1 ID0 0x04/0x05 FLAG: FLAG bit is set to `1' when the FLAG output is logic-low. The FLAG bit allows to quickly access the status of the device without using the FLAG output and without having to read all the fault registers. LHIGHZ: The LHIGHZ bit is set to `1' when the left-channel output is high impedance; for example due to a short circuit. RHIGHZ: The RHIGHZ bit is set to `1' when the right-channel output is high impedance; for example due to a short circuit. OFFSETL: The OFFSETL bit is set to `1' when excessive offset is detected on the left-channel output. OFFSETR: The OFFSETR bit is set to `1' when excessive offset is detected on the right-channel output. ID[2:0]: The ID[2:0] bits indicate the device type (12dB = 100 and 0dB = 101). General Mask Register Table 8. General Mask Register Format FUNCTION ADDRESS CODE (HEX) General Mask Register 0x06 REGISTER DATA D7 D6 D5 D4 D3 D2 D1 D0 POR STATE (HEX) 0 MTWARN MTSHDN MDUMP x x x x 0x00 MTWARN: Set MTWARN to `1' to enable the TWARN fault detection. See Table 4. MTSHDN: Set MTSHDN to `1' to enable the TSHDN fault detection. See Table 4. MDUMP: Set MDUMP to `1' to enable the DUMP fault detection. See Table 4. Left-Channel Mask Register Table 9. Left-Channel Mask Register FUNCTION ADDRESS CODE (HEX) Left-Channel Mask Register 0x07 REGISTER DATA D7 D6 D5 D4 D3 D2 D1 D0 MSVDDL MSGNDL MLIMITL 0 MOFFSETL MOPENL x x POR STATE (HEX) 0x00 MSVDDL: Set MSVDDL to 1 to enable the short to VDD detection on the left channel. MSGNDL: Set MSGNDL to 1 to enable the short to GND detection on the left channel. MLIMITL: Set MLIMITL to 1 to enable overcurrent detection on the left channel. MOFFSETL: Set MOFFSETL to 1 to enable excessive-offset detection on the left-channel output. MOPENL: Set MOPENL to 1 to enable open-load detection on the left channel. 12 Maxim Integrated MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic Right-Channel Mask Register Table 10. Right-Channel Mask Register FUNCTION ADDRESS CODE (HEX) Right-Channel Mask Register 0x08 REGISTER DATA D7 D6 D5 D4 D3 D2 D1 D0 MSVDDR MSGNDR MLIMITR 0 MOFFSETR MOPENR x x POR STATE (HEX) 0x00 MSVDDR: Set MSVDDR to 1 to enable the short to VDD detection on the right channel. MSGNDR: Set MSGNDR to 1 to enable the short to GND detection on the right channel. MLIMITR: Set MLIMITR to 1 to enable overcurrent detection on the right channel. MOFFSETR: Set MOFFSETR to 1 to enable excessive-offset detection on the right channel. MOPENR: Set MOPENR to 1 to enable open-load detection on the right channel. I2C and Stand-Alone Diagnostics When the DIAG bit and the appropriate mask bits are set to 1, the MAX13325/MAX13326 enter diagnostic mode. In this mode, the MAX13325/MAX13326 detect short to GND, short to battery, overcurrent condition, overtemperature condition, excessive offset, and report the diagnosis using the I2C serial interface, FLAG bit, and the FLAG output. For stand-alone mode, there exists a 500ms stand-alone fault retry function (for autoretry) until the fault goes away. The FLAG output is pulsed to indicate a fault. Output Short to VDD When in diagnostic mode, the MAX13325/MAX13326 detect if any of the differential outputs is shorted to VDD or battery. Upon detection of the short to VDD or battery, the faulted channel is switched off and its output goes into a high-impedance state. The fault is reported using the I2C interface and the FLAG output. See Table 11. Table 11. Output Short to VDD/Battery Diagnostic FAULT CONDITION STATUS REPORT FLAG is asserted low. FLAG bit set. See Table 7. Left-Channel Output Short to VDD SVDDL bit is set in the LFAULT register. See Table 5. Left channel switches off and output goes to high-impedance state. FLAG is asserted low. FLAG bit set. See Table 7. Right-Channel Output Short to VDD Maxim Integrated SVDDR bit is set in the RFAULT register. See Table 6. Right channel switches off and output goes to high-impedance state. UNMASK RECOVERY In LMASK register, set MSVDDL bit to 1. See Table 9. Cleared on reading the LFAULT register. See Table 5. Note: 500ms autoretry in standalone mode. Cannot be masked. Output is enabled by setting the RETRYL bit to 1 in the Common Byte register. See Table 3. In RMASK register, set MSVDDR bit to 1. See Table 10. Cleared on reading the RFAULT register. See Table 6. Note: 500ms autoretry in standalone mode. Cannot be masked. Output is enabled by setting the RETRYR bit to 1 in the Command Byte register. See Table 3. 13 MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic Output Short to GND When in diagnostic mode, the MAX13325/MAX13326 detect if any of the differential outputs is shorted to ground. Upon detection of the short to ground, the faulted channel is switched off and its output goes into a high-impedance state. The fault is reported using the I2C interface and the FLAG output. See Table 12. Overtemperature When in diagnostic mode, if the MAX13325/MAX13326 exceed the overtemperature warning or temperature shutdown thresholds the device reports the condition using the I2C interface and the FLAG output. See Table 13. Table 12. Output Short to GND Diagnostic FAULT CONDITION STATUS REPORT FLAG is asserted low. FLAG bit set. See Table 7. Left-Channel Output Short to GND SGNDL bit is set in the LFAULT register. See Table 5. Left channel switches off and output goes to high-impedance state. FLAG is asserted low. FLAG bit set. See Table 7. Right-Channel Output Short to GND SGNDR bit is set in the RFAULT register. See Table 6. Right channel switches off and output goes to high-impedance state. UNMASK RECOVERY In LMASK register, set MSGNDL bit to 1. See Table 9. Cleared on reading the LFAULT register. See Table 5. Note: 500ms autoretry in standalone mode. Cannot be masked. Output is enabled by setting the RETRYL bit to 1 in the Command Byte register. See Table 3. In RMASK register, set MSGNDR bit to 1. See Table 10. Cleared on reading the RFAULT register. See Table 6. Note: 500ms autoretry in standalone mode. Cannot be masked. Output is enabled by setting the RETRYR bit to 1 in the Command Byte register. See Table 3. Table 13. Overtemperature Diagnostic FAULT CONDITION Overtemperature Warning STATUS REPORT FLAG is asserted low. FLAG bit set. See Table 7. TWARN bit is set in the GFAULT register. See Table 4. UNMASK RECOVERY In GMASK register, set MTWARN bit to 1. See Table 8. Die temperature falls below warning threshold. Cleared on reading the GFAULT register. In GMASK register, set MTSHDN bit to 1. See Table 8. Die temperature falls below shutdown threshold. Cleared on reading the GFAULT register. Note: 500ms autoretry in standalone mode. Cannot be masked. Left channel is enabled by setting the RETRYL bit to 1 in the Command Byte register. Right channel is enabled by setting the RETRYR bit to 1 in the Command Byte register. See Table 3. FLAG is asserted low. FLAG bit set. See Table 7. TSHDN bit is set in the GFAULT Register. See Table 4. Overtemperature Shutdown Left and right channels switch off and output goes to highimpedance state. 14 Maxim Integrated MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic Excessive Offset When in diagnostic mode with mute enabled, if there is excessive offset on any output, the MAX13325/ MAX13326 reports the condition through the I2C interface and the FLAG output. See Table 14. Overcurrent When in diagnostic mode, if any of the output pairs is excessively loaded, the MAX13325/MAX13326 issue a warning and report the condition through the I2C interface and the FLAG output. The faulted channel is not switched off. See Table 15. Open Load When in diagnostic mode and the open-load detection is initiated, the selected channel is switched off for 1ms during which the diagnosis is taking place. Upon detecting an open load on any channel, the MAX13325/ MAX13326 report the condition using the I2C interface and the FLAG output. See Table 16. Overvoltage When in diagnostic mode, if the MAX13325/MAX13326 exceed the VDD overvoltage threshold (for example during a load-dump condition), the device reports the condition using the I2C interface and the FLAG output. See Table 17. Table 14. Excessive Offset Diagnostic FAULT CONDITION Excessive Output Offset on Left Channel Excessive Output Offset on Right Channel STATUS REPORT FLAG is asserted low. FLAG bit set. See Table 7. OFFSETL bit is set in the LFAULT register. See Table 5. FLAG is asserted low. FLAG bit set. OFFSETR bit is set in the RFAULT register. See Table 6. UNMASK RECOVERY In the LMASK register, set MOFFSETL bit to 1. See Table 9. Cleared on reading the LFAULT register. In the RMASK register, set MOFFSETR bit to 1. See Table 10. Cleared on reading the RFAULT register. UNMASK RECOVERY In the LMASK register, set MLIMITL bit to 1. See Table 9. Load current falls below the current-limit threshold. Cleared on reading the LFAULT register. In the RMASK register, set MLIMITR bit to 1. See Table 10. Load current falls below the current-limit threshold. Cleared on reading the RFAULT register. UNMASK RECOVERY In the LMASK register, set MOPENL bit to 1. See Table 9. Cleared on reading the LFAULT register. In the RMASK register, set MOPENR bit to 1. See Table 10. Cleared on reading the RFAULT register. Table 15. Overcurrent Diagnostic FAULT CONDITION Overcurrent on Left Channel Overcurrent on Right Channel STATUS REPORT FLAG is asserted low. FLAG bit set. See Table 7. LIMITL bit is set in the LFAULT register. See Table 5. FLAG is asserted low. FLAG bit set. See Table 7. LIMITR bit is set in the RFAULT register. See Table 6. Table 16. Open-Load Diagnostic FAULT CONDITION Left-Channel Open Load Right-Channel Open Load Maxim Integrated STATUS REPORT FLAG is asserted low. FLAG bit set. See Table 7. OPENL bit is set in the LFAULT register. See Table 5. FLAG is asserted low. FLAG bit set. See Table 7. OPENR bit is set in the RFAULT register. See Table 6. 15 MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic Table 17. Overvoltage Diagnostic FAULT CONDITION STATUS REPORT FLAG is asserted low. FLAG bit set. See Table 7. DUMP bit is set in the GFAULT register. See Table 4. Overvoltage Shutdown Left and right channels switch off and output goes to a high-impedance state. Applications Information Serial Interface Writing to the MAX13325/MAX13326 using I2C requires that first the master sends a START (S) condition followed by the device's I2C address. After the address, the master sends the register address of the register that is to be programmed. The master then ends communication by issuing a STOP (P) condition to relinquish UNMASK RECOVERY In GMASK register, set MDUMP bit to 1. See Table 8. VDD voltage falls below overvoltage threshold. Cleared on reading the GFAULT register. Note: 500ms autoretry in stand-alone mode. Cannot be masked. Left channel is enabled by setting the RETRYL bit to 1. Right channel is enabled by setting the RETRYR bit to 1. See Table 3. control of the bus, or a Repeated START (Sr) condition to communicate to another I2C slave (see Figure 1). Bit Transfer Each SCL rising edge transfers one data bit. The data on SDA must remain stable during the high portion of the SCL clock pulse (see Figure 2). Changes in SDA while SCL is high are read as control signals (see the START and STOP Conditions section). When the serial interface is inactive, SDA and SCL idle high. SDA tF tLOW tLOW tSU:DAT tHD:STA tF tSP tR tBUF SCL tHD:STA S tHD:DAT tHIGH tSU:STA tSU:STO Sr P S Figure 1. I2C Timing SDA SCL DATA LINE STABLE; DATA VALID CHANGE OF DATA ALLOWED Figure 2. Bit Transfer 16 Maxim Integrated MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic START and STOP Conditions A master device initiates communication by issuing a START condition, which is a high-to-low transition on SDA with SCL high. A START condition from the master signals the beginning of a transmission to the MAX13325/MAX13326. The master terminates transmission by a STOP condition (see the Acknowledge Bit section). A STOP condition is a low-to-high transition on SDA while SCL is high (Figure 3). The STOP condition frees the bus. If a Repeated START condition is generated instead of a STOP condition, the bus remains active. When a STOP condition or incorrect slave ID is detected, the device internally disconnects SCL from the serial interface until the next START or Repeated START condition, minimizing digital noise and feedthrough. Acknowledge Bit The acknowledge (ACK) bit is a clocked 9th bit that the MAX13325/MAX13326 use to handshake receipt of each byte of data when in write mode. The MAX13325/ MAX13326 pull down SDA during the entire mastergenerated 9th clock pulse if the previous byte is successfully received (see Figure 4). Monitoring ACK allows for detection of unsuccessful data transfers. An unsuccessful data transfer occurs if a receiving device is busy or if a system fault has occurred. In the event START CONDITION STOP CONDITION SDA SCL Figure 3. START/STOP Conditions NOT ACKNOWLEDGE S SDA ACKNOWLEDGE 1 SCL 8 9 Figure 4. Acknowledge and Not-Acknowledge Bits Table 18. Slave Address ADD1 ADD0 A6 A5 A4 A3 A2 A1 A0 R/W SLAVE ADDRESS READ (HEX) SLAVE ADDRESS WRITE (HEX) MODE GND GND -- -- -- -- -- -- -- -- -- -- Standalone VL GND 1 1 0 0 0 0 1 1/0 0xC3 0xC2 I2C GND VL 1 1 0 0 0 1 0 1/0 0xC5 0xC4 I2C VL VL 1 1 0 0 0 1 1 1/0 0xC7 0xC6 I2C SCL VL 1 1 0 0 1 0 0 1/0 0xC9 0xC8 I2C SDA VL 1 1 0 0 1 0 1 1/0 0xCB 0xCA I2C VL SCL 1 1 0 0 1 1 0 1/0 0xCD 0xCC I2C VL SDA 1 1 0 0 1 1 1 1/0 0xCF 0xCE I2C Maxim Integrated 17 MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic of an unsuccessful data transfer, the bus master may retry communication. The master must pull down SDA during the 9th clock cycle to acknowledge receipt of data when the MAX13325/MAX13326 are in read mode. An acknowledge must be sent by the master after each read byte to allow data transfer to continue. A notacknowledge is sent when the master reads the final byte of data from the MAX13325/MAX13326, followed by a STOP condition. Register Address Map Single-Byte Write Operation For a single-byte write operation, send the slave address as the first byte followed by the register address and then a single data byte (see Figure 5). Burst Write Operation For a burst write operation, send the slave address as the first byte followed by the register address and then the data bytes (see Figure 6). Slave Address The MAX13325/MAX13326 are programmable to one of seven I2C slave addresses. These slave addresses are unique device IDs. Connect ADD_ to GND, VL, SCL, or SDA to set the I2C slave address. The address is defined as the seven most significant bits (MSBs) followed by the read/write bit. Set the read/write bit to 1 to configure the MAX13325/MAX13326 to read mode. Set the read/ write bit to 0 to configure the device to write mode. The address is the first byte of information sent after the START condition. S S7 S6 S5 S4 S3 S2 R/W =0 S1 Single-Byte Read Operation For a single-byte read operation, send the slave address with the read bit set, as the first byte followed by the register address. Then send a Repeated START condition followed by the slave address. After the slave sends the data byte, send a not-acknowledge followed by a STOP condition (see Figure 7). Burst Read Operation For a burst read operation, send the slave address with a write as the first byte followed by the register address. Then send a Repeated START condition followed by the slave address. The slave sends data bytes until a notacknowledge condition is sent (see Figure 8). ACK C7 C6 C5 SLAVE ADDRESS B7 B6 B5 B4 B3 C4 C3 C2 C1 C0 ACK REGISTER ADDRESS B2 B1 B0 ACK P DATA 1 Figure 5. A Single-Byte Write Operation S S7 S6 S5 S4 S3 S2 S1 R/W =0 ACK R7 R6 SLAVE ADDRESS B7 B6 B5 B4 B3 R5 R4 R3 R2 R1 R0 ACK B2 B1 B0 ACK B2 B1 B0 ACK REGISTER ADDRESS B2 B1 B0 ACK B7 B6 B5 DATA 1 B4 B3 DATA 2 ACK B7 B6 B5 B4 B3 P DATA N Figure 6. A Burst Write Operation 18 Maxim Integrated MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic S S7 S6 S5 S4 S3 S2 R/W =0 S1 ACK B7 B6 B5 SLAVE ADDRESS Sr S7 S6 S5 S4 B4 B3 B2 B1 B0 ACK B1 B0 NACK REGISTER ADDRESS S3 S2 R/W =1 S1 ACK B7 B6 B5 B4 SLAVE ADDRESS B3 B2 P DATA Figure 7. A Single-Byte Read Operation S S7 S6 S5 S4 S3 S2 S1 R/W =0 ACK B7 B6 B5 SLAVE ADDRESS Sr S7 S6 S5 S4 S3 B4 B3 B2 B1 B0 ACK B2 B1 B0 ACK B1 B0 NACK P REGISTER ADDRESS S2 S1 R/W =1 ACK B7 B6 B5 B4 SLAVE ADDRESS B3 DATA 1 ACK B7 B6 B5 B4 B3 B2 DATA N Figure 8. A Burst Read Operation Charge Pump The MAX13325/MAX13326 charge pump can be disabled depending on application requirements. When charge pump is enabled [CPOFF = 0], please follow the charge-pump capacitor selections. When the charge pump is disabled [CPOFF = 1], the flying capacitor (C1) is not needed. There are internal diodes between VDD/OUT_ to CHOLD, so it is important that CHOLD not be forced below VDD or any of the outputs. A series diode needs to be placed between the external supply (VSUP) and CHOLD. See D2 in the Typical Operating Circuit. Charge-Pump Capacitor Selection Use ceramic capacitors with a low ESR for optimum performance. For optimal performance over the extended temperature range, select capacitors with an X7R dielectric. Table 19 lists suggested manufacturers. Flying Capacitor (C1) The value of the flying capacitor (see the Typical Operating Circuit) affects the charge pump's load regulation and output resistance. A C1 value that is too small degrades the device's ability to provide sufficient current drive, which leads to a loss of output voltage. Increasing the value of C1 improves load regulation and reduces the charge-pump output resistance. For optimum performance, use a 470nF capacitor for C1. When the charge pump is disabled [CPOFF = 1], the flying capacitor (C1) is not needed. Hold Capacitor (C2) The hold capacitor value (see the Typical Operating Circuit) and ESR directly affect the ripple at the internal negative rail. Increasing the value of C2 reduces output ripple. Likewise, decreasing the ESR of C2 reduces both ripple and output resistance. Lower capacitance values can be used in systems with low maximum output power levels. For optimum performance, use a 1FF capacitor for C2. Table 19. Suggested Capacitor Vendors PHONE FAX Murata Electronics North America, Inc. SUPPLIER 770-436-1300 770-436-3030 www.murata-northamerica.com Taiyo Yuden 800-348-2496 847-925-0899 www.t-yuden.com TDK Corp. 847-803-6100 847-390-4405 www.component.tdk.com Maxim Integrated WEBSITE 19 MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic Power-Supply Bypass Capacitor (C3) The power-supply bypass capacitor (see the Typical Operating Circuit) lowers the output impedance of the power supply, and reduces the impact of the MAX13325/ MAX13326 charge-pump switching transients. Bypass VDD with C3, the same value as C2, and place it physically close to the VDD and PGND pins. Load-Dump Protection With minimal external components, the MAX13325/ MAX13326 can be protected against automotive loaddump conditions. See the Typical Operating Circuit. nMOSFET (Q1) Q1 should be selected to withstand the full-voltage exposure (BVDSS > 45V). The gate-source turn-on voltage should be chosen to be less than VCPS to ensure initial startup. Using an external nMOS, RTR020N05, 300ms duration component provides 50V load-dump protection. Zener Diode (D1) During short-to-battery condition, OUT_ lifts up CHOLD using an internal diode. In order not to violate the maximum gate-source voltage of Q1, a zener diode of appropriate clamping voltage should be added between the gate and source terminals. Series Resistor (R1) Normally, a series resistor for current limitation is needed during short-to-battery condition. R1 should be chosen according to (18V - VDD(min) - VZENER)/1mA so that no excessive current is being drawn from CHOLD. Layout and Grounding Proper layout and grounding are essential for optimum performance. Connect the EP and GND together at a single point on the PCB. Ensure ground return resistance is minimized for optimum crosstalk performance. Chip Information PROCESS: BCD 20 Package Information For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 28 TSSOP-EP U28E+5 21-0108 90-0147 Maxim Integrated MAX13325/MAX13326 Dual Automotive, Audio Line Drivers with I2C Control and Diagnostic Revision History REVISION NUMBER REVISION DATE DESCRIPTION PAGES CHANGED 0 1/10 Initial release -- 1 3/10 Updated the Typical Operating Circuit 1 Added new register bits to Tables 1, 2, and 7. Revised FLAG Register section and added Table 2a and Charge Pump section. Introduced the MAX13326. Updated the Electrical Characteristics table and added new Typical Operating Characteristics graphs. 2 4/10 1, 4, 7, 8-12, 19, 20 3 6/10 4 9/12 Corrected slave addresses in Table 18 17 5 4/13 Corrected bits D[7:6] in Table 3 10 1, 4, 5, 7 Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. Maxim Integrated 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-1000 (c) 2013 Maxim Integrated 21 The Maxim logo and Maxim Integrated are trademarks of Maxim Integrated Products, Inc.