19-5221; Rev 0; 5/10 MAX98500 Evaluation Kit The MAX98500 evaluation kit (EV kit) is a fully assembled and tested circuit board that uses the MAX98500 boosted Class D amplifier to drive a mono bridge-tied-load (BTL) speaker in portable audio applications. Designed to operate from a 2.5V to 5.5V DC power supply, the EV kit delivers 2.2W into an 8I load. The EV kit accepts differential or single-ended input signals, features three selectable gain settings (6dB, 15.5dB, and 20dB), and provides separate speaker and boost shutdown inputs. Features S 2.5V to 5.5V Single-Supply Operation S Output Power: 2.2W into 8, 10% THD+N S Selectable Gain Settings (6dB, 15.5dB, and 20dB) S Boosted Class D Output S Differential or Single-Ended Input Signals S Boost Converter Shutdown S Speaker Output Shutdown S Fully Assembled and Tested Ordering Information PART TYPE MAX98500EVKIT+ EV Kit +Denotes lead(Pb)-free and RoHS compliant. Component List DESIGNATION QTY DESCRIPTION DESIGNATION QTY REQUIRED COMPONENTS C1 C2 C3, C4 C5 C8 C9, C10 C12, C13 1 1 DESCRIPTION 10FF Q10%, 6.3V X7R ceramic capacitor (0805) Murata GRM21BR70J106K TDK C2012X7R0J106K C14-C18 5 0.22FF Q10%, 25V X7R ceramic capacitors (0603) Murata GRM188R71E224K TDK C1608X7R1E224K FB1 1 0I resistor (0603) 22FF Q20%, 16V X5R ceramic capacitor (1206) Murata GRM31CR61226M Taiyo Yuden EMK316BJ226M FB2, FB3 0 Not installed, ferrite beads (0603) J1 1 Phono jack, black (side-entry PCB mount) JU1, JU2, JU3 3 3-pin headers JU4 1 2-pin header L1 1 2.2FH, 34mI, 4.5A inductor TOKO FDV0530S-2R2M (5mm x 5mm x 3mm) TDK LTF5022T-2R2N3R2-LC (5mm x 5mm x 2.2mm) NEC MPLC0525L2R2 (5.2mm x 6.2mm x 2.5mm) L2, L3 0 Not installed, inductors TOKO A916CY-220M (provided with EV kit) OUT-, OUT+, PGND, RKNEE 4 Test points R1 1 27.4k Q1% resistor (0603) R2, R3 2 22 Q5% resistors (0603) 2 1FF Q10%, 25V X7R ceramic capacitors (0603) Murata GRM188R71E105K Murata GRM188R71E105M 1 22FF Q10%, 6.3V X5R ceramic capacitor (0805) Murata GRM21BR60J226M TDK C2012X5R0J226K 1 0.1FF Q10%, 16V X7R ceramic capacitor (0402) Murata GRM155R71C104K TDK C1005X7R1C104K 0 Not installed, ceramic capacitors (0402) 0 Not installed, ceramic capacitors (0603) ________________________________________________________________ Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com. Evaluates: MAX98500 General Description Evaluates: MAX98500 MAX98500 Evaluation Kit Component List (continued) DESIGNATION QTY U1 DESCRIPTION DESIGNATION 1 VCCOUT 0 Not installed, test point -- 4 Shunts -- 1 PCB: MAX98500 EVALUATION KIT+ QTY DESCRIPTION OPTIONAL COMPONENTS Boosted Class D amplifier (16 WLP) Maxim MAX98500EWE+ L2, L3 22FH Q20%, 0.7A inductors (D63CB) TOKO A916CY-220M 2 Component Suppliers SUPPLIER PHONE WEBSITE Murata Electronics North America, Inc. 770-436-1300 www.murata-northamerica.com NEC TOKIN America, Inc. 408-324-1790 www.nec-tokinamerica.com TDK Corp. 847-803-6100 www.component.tdk.com TOKO America, Inc. 847-297-0070 www.tokoam.com Note: Indicate that you are using the MAX98500 when contacting these component suppliers. Quick Start Recommended Equipment * 2.5V to 5.5V, 4A DC power supply * 8I speaker * Mono audio signal source Procedure The MAX98500 EV kit is fully assembled and tested. Follow the steps below to verify board operation. Caution: Do not turn on the power supply until all connections are completed. 1) Verify that shunts are installed as follows: JU1: Open (15.5dB gain) JU2: Pins 1-2 (speaker enabled) JU3: Pins 1-2 (boost enabled) JU4: Short (single-ended/unbalanced input) 2) Set the power-supply output to 3.6V. 3) Disable the power-supply output. 4) Connect the power-supply ground to the PGND pad and the power-supply positive output to the VBAT pad on the EV kit. Keep VBAT lengths < 6in and twisted to minimize inductance, to ensure proper device operation. 5) Verify that the audio source output is disabled. 6) Connect the mono audio source between the IN+ and IN- pads or J1 on the EV kit. 7) Connect the speaker across the OUT+ and OUTtest points. 8) Enable the power-supply output. 9) Enable the audio source. 10) Verify that the speaker is playing the audio source signal. Detailed Description of Hardware The MAX98500 EV kit features the MAX98500 boosted Class D amplifier IC, designed to drive a BTL mono speaker in portable audio applications. The EV kit accepts a differential or single-ended audio input, features three selectable gain settings (6dB, 15.5dB, and 20dB), and provides two active-low shutdown inputs for flexibility. The audio input source is amplified to drive 2.2W into an 8I speaker. The EV kit operates from a single DC power supply that provides 2.5V to 5.5V. The EV kit provides two sets of differential outputs. The device outputs (OUT+ and OUT-) can be connected directly to a speaker load without any filtering. However, a filter can be added to ease evaluation. 2 _______________________________________________________________________________________ MAX98500 Evaluation Kit Optional Output Filtering The MAX98500 speaker amplifier is designed to pass FCC emissions standards without any filtering. When evaluating the MAX98500 without any filtering, connect the speaker to the output test points (OUT+, OUT-). Shutdown Inputs Jumper JU4 provides the option to select between a differential or single-ended input mode for the EV kit. See Table 3 for JU4 configuration. The EV kit also features PCB pads for a lowpass filter that can be added to ease evaluation. Audio analyzers typically cannot accept the Class D amplifier's pulsewidth-modulated (PWM) waveform at their inputs. The lowpass filter extracts the audio content from the PWM output signal and allows the device to be connected directly to an audio analyzer. The PWM output signal can be lowpass-filtered by simply installing L2 and L3; all other components are populated. The filtered outputs should then be monitored at the FOUT+/FOUT- pads. See Table 4 for suggested filtering components for an 8I load. Table 1. Gain Input (JU1) Table 3. Input Mode (JU4) The MAX98500 features two active-low shutdown inputs (SDSPK and SDBST). Jumper JU2 enables or disables the speaker amplifier (SDSPK) and jumper JU3 controls the boost converter (SDBST). See Table 2 for jumpers JU2 and JU3 configuration. Note that the boost must be enabled for the speaker amplifier to enable. Input Mode SHUNT POSITION GAIN PIN GAIN SETTING (dB) 2-3 Not installed* 1-2 Connected to AGND Unconnected Connected to VBAT 6 15.5 20 *Default position. Table 2. Shutdown Configuration (JU2, JU3) SHUNT POSITION IN- PIN INPUT MODE Installed* Connected to AGND Single-ended/ unbalanced input Not installed Connected to usersupplied negative differential output Differential input *Default position. SDSPK PIN (JU2) SDBST PIN (JU3) BOOST STATUS SPEAKER STATUS 2-3 (low) 1-2 (high) 2-3 (low) 1-2* (high) *Default position. 2-3 (low) 2-3 (high) 1-2 (low) 1-2* (high) Off Off On On Off Off Off On Table 4. Suggested Filtering Components for 8I Load DESIGNATION QTY DESCRIPTION L2, L3 2 22FH Q20%, 0.7A inductor (D63CB) TOKO A916CY-220M _______________________________________________________________________________________ 3 Evaluates: MAX98500 Selectable Gain Setting The MAX98500 features three internal gain settings that are selectable with the GAIN input. Jumper JU1 controls the amplifier's gain select input. See Table 1 for jumper JU1 configuration. Evaluates: MAX98500 MAX98500 Evaluation Kit Figure 1. MAX98500 EV Kit Schematic 4 _______________________________________________________________________________________ MAX98500 Evaluation Kit Figure 2. MAX98500 EV Kit Component Placement Guide-- Component Side 1.0" Figure 3. MAX98500 EV Kit PCB Layout--Component Side 1.0" Figure 4. MAX98500 EV Kit PCB Layout--Solder Side _______________________________________________________________________________________ 5 Evaluates: MAX98500 1.0" MAX98500 Evaluation Kit Evaluates: MAX98500 Revision History REVISION NUMBER REVISION DATE 0 5/10 DESCRIPTION Initial release PAGES CHANGED -- Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 6 (c) Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 2010 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.