MIC2225 2MHz 600mA Synchronous Buck Regulator with 300mA LDO General Description Features The Micrel MIC2225 is a dual output regulator featuring a high efficiency 2MHz PWM synchronous buck (step-down) regulator and a 300mA LDO. The MIC2225 is an ultra-low noise, small size, and high efficiency solution for portable power applications, providing core and I/O supply rails for applications like application processors, camera DSPs and multimedia chipsets. In PWM mode, the MIC2225 operates with a constant 2MHz frequency. The MIC2225 switching regulator operates from 2.7V to 5.5V input and features internal power MOSFETs that can supply up to 600mA output current in PWM mode. The MIC2225 is available in the 10-pin 2mm x 2mm Thin MLF(R) package with a junction operating range from -40C to +125C. Data sheets and support documentation can be found on Micrel's web site at: www.micrel.com. DC-DC Converter * 2.7 to 5.5V supply voltage * 2MHz PWM mode * Output current to 600mA * >95% efficiency * 100% maximum duty cycle * Fixed output voltage option down to 1V * Ultra-fast transient response * Stable with 2.2F ceramic output capacitor * Fully integrated MOSFET switches * Micropower shutdown (1mA in shutdown) * Thermal shutdown and current limit protection * Pb-free 10-pin 2mm x 2mm Thin MLF(R) package * -40C to +125C junction temperature range LDO * VIN range 2.7V to 5.5V * 300mA output current * Output voltage down to 0.8V * Thermal shutdown protection * Current limit protection Applications * Cellular phones * PDAs * USB peripherals ___________________________________________________________________________________________________________ Typical Application 1.8V Efficiency @ 25C 100 90 2.7VIN 80 70 60 50 3.6VIN 5.5VIN 40 30 20 10 0 0 0.1 0.2 0.3 0.4 0.5 LOAD CURRENT (A) 0.6 MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc. Micrel Inc. * 2180 Fortune Drive * San Jose, CA 95131 * USA * tel +1 (408) 944-0800 * fax + 1 (408) 474-1000 * http://www.micrel.com February 2008 M9999-022008-D Micrel, Inc. MIC2225 Ordering Information Part Number Marking Code Voltage* Temperature Range Package MIC2225-4KYMT 4TK 1.2V/2.6V -40 to +125C 10-Pin 2x2 Thin MLF(R) Pb-Free (R) Pb-Free Lead Finish MIC2225-4MYMT 4TM 1.2V/2.8V -40 to +125C 10-Pin 2x2 Thin MLF MIC2225-4OYMT 4TO 1.2V/2.9V -40 to +125C 10-Pin 2x2 Thin MLF(R) Pb-Free -40 to +125C 10-Pin 2x2 Thin MLF (R) Pb-Free (R) Pb-Free MIC2225-4SYMT 4TS 1.2V/3.3V MIC2225-G4YMT GT4 1.8V/1.2V -40 to +125C 10-Pin 2x2 Thin MLF MIC2225-GFYMT GTF 1.8V/1.5V -40 to +125C 10-Pin 2x2 Thin MLF(R) Pb-Free -40 to +125C 10-Pin 2x2 Thin MLF (R) Pb-Free 10-Pin 2x2 Thin MLF (R) Pb-Free MIC2225-GJYMT MIC2225-GMYMT GTJ GTM 1.8V/2.5V 1.8V/2.8V -40 to +125C Note: MLF(R) is a GREEN RoHS compliant package. Lead finish is NiPdAu. Mold compound is Halogen Free. Other voltage options available. Please contact Micrel for details. * Refers to nominal output voltage of DC/DC and LDO respectively. Pin Configuration AGND 1 10 PGND LDO 2 9 SW BIAS 3 8 VIN AVIN 4 7 ENLDO FB 5 6 EN 10-Pin 2mm x 2mm Thin MLF(R) (MT) February 2008 2 M9999-022008-D Micrel, Inc. MIC2225 Pin Description Pin Number Pin Name 1 AGND 2 LDO LDO Output (Output): Connect to a 2.2F output capacitor. 3 BIAS Internal circuit bias supply. Must be de-coupled to signal ground with a 0.1F capacitor and should not be loaded. 4 AVIN Analog Supply Voltage (Input): Supply voltage for the analog control circuitry and LDO input power. Requires bypass capacitor to GND. It must be tied to VIN. 5 FB Feedback. Input to the error amplifier. For the Adjustable option, connect to the external resistor divider network to set the output voltage. For fixed output voltage options, connect to VOUT and an internal resistor network sets the output voltage. 6 EN Enable (Input). Logic low will shut down the switching regulator reducing the quiescent current to less than 5A. 7 ENLDO 8 VIN 9 SW 10 PGND February 2008 Pin Function Analog (signal) Ground. Enable LDO (Input): Logic low will shut down the LDO, reducing the quiescent current to less than 5A. Supply Voltage (Input): Supply voltage for the internal switches and drivers. Switch (Output): Internal power MOSFET output switches. Power Ground. 3 M9999-022008-D Micrel, Inc. MIC2225 Absolute Maximum Ratings(1) Operating Ratings(2) Supply Voltage (VIN) .......................................................+6V Output Switch Voltage (VSW) ..........................................+6V Output Switch Current (ISW)..............................................1A Logic Input Voltage (VEN,VLOWQ)........................ -0.3V to VIN Storage Temperature (Ts) .........................-60C to +150C ESD Rating(3) .................................................................. 2kV Supply Voltage (VIN)..................................... +2.7V to +5.5V Logic Input Voltage (VEN,VLOWQ)........................ -0.3V to VIN Junction Temperature (TJ) ........................ -40C to +125C Junction Thermal Resistance Thin MLF-10L (JA) ............................................90C/W Electrical Characteristics DC/DC(4) VEN = VIN = 3.6V, L = 2.2H; COUTDC/DC = 2.2F, CLDO = 2.2F; IOUTDC/DC = 100mA; CBIAS = 0.1F VENLDO = 0V; TJ = 25C, bold values indicate -40C < TJ < +125C; unless noted. Parameter Condition Min Typ Max UVLO Threshold Rising input voltage during turn-on 2.45 2.55 2.65 UVLO Hysteresis 70 Units V mV Switcher Ground Pin Current ENLDO = 0V, VFB = GND ; IL=0mA 850 1100 A LDO Ground Pin Current EN = 0V 67 110 A Ground Pin Current in Shutdown EN +ENLDO = 0V 0.2 5 A Over-temperature Shutdown 160 C Over-temperature Shutdown Hysteresis 23 C Enable Input Voltage Logic Low Logic High Enable Input Current 0.2 V V 1.0 VIL < 0.2V 0.1 1 A VIH > 1.0V 0.1 1 A Turn-on Time ILOAD = 5mA 50 Fixed Output Voltages Nominal VOUT tolerance Io=50mA Current Limit in PWM Mode VFB = 0.9*VNOM Output Voltage Line Regulation VIN = 2.7V to 5.5V, ILOAD= 100mA Output Voltage Load Regulation 20mA < ILOAD < 300mA Maximum Duty Cycle VFB 0.4V PWM Switch ON-Resistance ISW = 150mA; VFB = 0.7VFB_NOM ISW = -150mA; VFB = 1.1VFB_NOM 0.675 +2 +3 % % 0.12 1 % % 0.2 1.5 % 0.95 A 100 % 0.4 0.4 Oscillator Frequency February 2008 -2 -3 s 1.8 4 2 2.2 MHz M9999-022008-D Micrel, Inc. MIC2225 Electrical Characteristics LDO(4) COUTLDO = 2.2F, IOUTLDO = 100A; TJ = 25C, bold values indicate -40C < TJ < +125C; unless noted. Parameter Input Voltage Output Voltage Accuracy Line Regulation Turn-on Time Load Regulation Dropout Voltage, Note 5 Ripple Rejection Current Limit Output Voltage Noise Condition Min Variation from nominal VOUT Variation from nominal VOUT; -40C to +125C VIN = VOUT +1V to 5.5V; IOUT = 100A ILOAD = 300mA IOUT = 100A to 300mA @ VIN = VOUT + 1 IOUT = 300mA @ VIN = 2.7V f = 1kHz; COUT = 2.2F f = 20kHz; COUT = 2.2F VOUT = 0V COUT = 2.2F, 10Hz to 100kHz Typ 2.7 -2.0 -3.0 0.2 30 0.70 210 43 17 400 470 Max Units 5.5 +2.0 +3.0 V % % % s % mV dB dB mA VRMS Notes: 1. Exceeding the absolute maximum rating may damage the device. 2. The device is not guaranteed to function outside its operating rating. 3. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF. 4. Specification for packaged product only. 5. Dropout voltage is defined as the input-to-output differential at which the output voltage drops 2% below its nominal value that is initially measured at a 1V differential. For outputs below 2.7V, the dropout voltage is the input-to-output voltage differential with a minimum input voltage of 2.7V. February 2008 5 M9999-022008-D Micrel, Inc. MIC2225 Typical Characteristics (DC-DC) 1.2V Efficiency @ -40C 100 90 2.7VIN 3.6VIN 80 1.2V Efficiency @ 25C 100 90 70 60 5.5VIN 50 40 50 40 30 30 20 10 20 10 150 0.1 0.2 0.3 0.4 0.5 LOAD CURRENT (A) 0.6 Quiescent Current vs. Input Voltage 0 0 1200 125 1000 100 800 75 600 50 VOUT = 1.2V LOAD = 0 ENLDO = 0V EN = VIN 25 0 2.5 100 90 3 3.5 4 4.5 5 INPUT VOLTAGE (V) 5.5 Turn-On Time vs. Input Voltage 3.6VIN 5.5VIN 0.1 0.2 0.3 0.4 0.5 LOAD CURRENT (A) 0.6 Quiescent Current vs. Load Current VOUT = 1.19V VLDO = 2.8V ENLDO = 5V 20 10 3 3.5 4 4.5 5 INPUT VOLTAGE (V) February 2008 5.5 5.5VIN 0.1 0.2 0.3 0.4 0.5 LOAD CURRENT (A) 0.6 Enable Threshold vs. Input Voltage 1.0 0.8 0.6 VOUT = 1.2V EN = VIN ENLDO = 0V 30 40 50 60 LOAD CURRENT (mA) Peak Current Limit vs. Input Voltage 0.4 VOUT = 1.19V ENLDO = 5V 0.2 0 2.5 2.9 3 3.5 4 4.5 5 INPUT VOLTAGE (V) 5.5 Frequency vs. Input Voltage 2.7 2.5 2.3 2.1 0.3 0.2 0.1 0 2.5 3.6VIN 1.2 0.5 0.4 40 30 10 0 0 1.4 0.7 0.6 60 50 2.7VIN 40 30 20 200 0 90 80 70 60 50 400 1.0 0.9 0.8 80 70 0 2.5 100 2.7VIN 80 70 60 0 0 1.2V Efficiency @ 70C 1.9 VOUT = 1.2V EN = ENLDO = VIN 3 3.5 4 4.5 5 INPUT VOLTAGE (V) 6 5.5 VOUT = 1.2V LOAD = 0 ENLDO = VIN 1.7 1.5 2.5 3 3.5 4 4.5 5 INPUT VOLTAGE (V) 5.5 M9999-022008-D Micrel, Inc. MIC2225 Typical Characteristics (LDO) PSRR 70 90 60 80 100mA 78 76 74 72 70 60 40 300mA 30 40 30 20 VIN = 1.7V 10 VOUT = 2.8V COUT = 2.2F 0 100 1K 10K FREQUENCY (Hz) 100 10 100K 0 0 3.00 2.95 ENLDO = VIN 1 2 3 4 INPUT VOLTAGE (V) 5 Output Voltage vs. Load Current 2.80 2.75 2.75 2.70 1mA 2.65 25 VIN = 3.6V ENLDO = VIN 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (C) Output Voltage vs. Temperature 2.86 2.60 2.55 VIN = 3.6V ENLDO = VIN 2.50 0.025 0.075 0.125 0.175 0.225 0.275 LOAD CURRENT (A) 0.20 0.18 2.84 2.82 Dropout Voltage vs. Load Current 2.70 2.65 2.60 50 40 30 2.76 0.12 0.10 2.74 2.72 0.08 0.06 20 VIN = 3.6V ENLDO = VIN Load = 10mA 2.70 2.68 2.66 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (C) 2.0 1.8 Peak Current Limit vs. Input Voltage 50 45 1.6 40 1.4 1.2 35 30 1.0 0.8 25 20 0.6 15 0.4 0.2 10 5 0 2.5 EN = ENLDO = VIN 3 3.5 4 4.5 5 INPUT VOLTAGE (V) February 2008 5.5 0 2.5 Dropout Voltage vs. Temperature ENLDO = VIN 50mA 0.04 0.02 0 0 VIN = 3.6V ENLDO = VIN Load = 1mA 2.55 2.50 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (C) 0.16 0.14 2.8 2.78 Output Voltage vs. Temperature 3.00 2.85 2.80 100mA VIN = 3.6V 62 ENLDO = VIN 60 0.025 0.075 0.125 0.175 0.225 0.275 LOAD CURRENT (A) 2.95 2.90 2.85 2.90 50mA 50 68 66 64 0mA 20 Quiescent Current vs. Temperature 125 100mA 50 10mA Quiescent Current vs. Load Current 80 60mA 70 50 75 Quiescent Current vs. Input Voltage VIN = 3.6V ENLDO = VIN 0.05 0.1 0.15 0.2 0.25 0.3 LOAD CURRENT (A) Turn-On Time vs. Input Voltage 25mA 10mA 10 1mA 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (C) 1.4 Enable Threshold vs. Input Voltage 1.2 1.0 0.8 0.6 0.4 0.2 ENLDO = VIN 3 3.5 4 4.5 5 INPUT VOLTAGE (V) 7 5.5 0 2.5 3 LDO = 2.8V 3.5 4 4.5 5 5.5 INPUT VOLTAGE (V) M9999-022008-D Micrel, Inc. MIC2225 Typical Characteristics (LDO) continued 3.0 Output Noise Spectral Density VIN = 3.6V VOUT = 3.3V COUT = 2.2F CBYP = 0.1F 2.5 2.0 Noise(10Hz-100kHz) = 169VRMS 1.5 1.0 0.5 0 10 100 1K 10K 100K FREQUENCY (Hz) February 2008 1M 8 M9999-022008-D Micrel, Inc. MIC2225 Functional Characteristics February 2008 9 M9999-022008-D Micrel, Inc. MIC2225 Functional Diagram VIN AVIN P-Channel Current Limit 6 BIAS HSD PWM Control SW VOUT1 Anti-Shoot Through COUT1 LSD N-Channel Current Limit EN ENLDO Enable and Control Logic Bias, UVLO, Thermal Shutdown Soft Start FB EA 1.0V LDO LDO Block LDO Current Limit EA VOUT2 COUT2 1.0V SGND PGND MIC2225 Block Diagram February 2008 10 M9999-022008-D Micrel, Inc. MIC2225 Functional Description BIAS The BIAS pin supplies the power to the internal power to the control and reference circuitry. The bias is powered from AVIN through an internal 6 resistor. A small 0.1F capacitor is recommended for bypassing. VIN VIN provides power to the MOSFETs for the switch mode regulator section, along with the current limiting sensing. Due to the high switching speeds, it is recommended that an 1F capacitor be placed close to VIN and the power ground (PGND) pin for bypassing. Please refer to layout recommendations. FB The feedback pin (FB) provides the control path to control the output. For fixed output, the controller output is directly connected to the feedback (FB) pin. AVIN Analog VIN (AVIN) provides power to the LDO section and the bias through an internal 6 resistor. AVIN and VIN must be tied together. Careful layout should be considered to ensure high frequency switching noise caused by VIN is reduced before reaching AVIN. SW The switch (SW) pin connects directly to the inductor and provides the switching current necessary to operate in PWM mode. Due to the high speed switching on this pin, the switch node should be routed away from sensitive nodes. LDO The LDO pin is the output of the linear regulator and needs to be connected to a 2.2F output capacitor. PGND Power ground (PGND) is the ground path for the high current PWM mode. The current loop for the power ground should be as small as possible and separate from the Analog ground (AGND) loop. Refer to the layout considerations for more details. EN The enable pin provides a logic level control of the output. In the off state, the supply current of the device is greatly reduced (typically <1A). Also, in the off state, the output drive is placed in a "tri-stated" condition, wherein both the high side P-channel MOSFET and the low-side N-channel are in an "off" or non-conducting state. Do not drive the enable pin above the supply voltage. SGND Signal ground (SGND) is the ground path for the biasing and control circuitry. The current loop for the signal ground should be separate from the Power ground (PGND) loop. Refer to the layout considerations for more details. ENLDO The enable pin provides a logic level control of the LDO output. In the off state, supply current of the device is greatly reduced (typically <1A). Do not drive the enable pin above the supply voltage. February 2008 11 M9999-022008-D Micrel, Inc. MIC2225 not recommended. In addition to a 2.2F, a small 10nF is recommended close to the load for high frequency filtering. Smaller case size capacitors are recommended due to there lower ESR and ESL. Application Information The MIC2225 is a 600mA PWM and 300mA LDO dual power supply. Both PWM output and LDO outputs are independent and are controlled by EN and ENLDO pins respectively. These enable pins are logic level compatible. Inductor Selection The MIC2225 is designed for use with a 2.2H inductor. Proper selection should ensure that the inductor can handle the maximum average and peak currents required by the load. Maximum current ratings for the inductor are generally given in two methods; permissible DC current and saturation current. Permissible DC current can be rated either for a 40C temperature rise or a 10% to 20% loss in inductance. Ensure that the inductor selected can handle the maximum operating current. When saturation current is specified, make sure that there is enough margin so that the peak current will not saturate the inductor. Peak inductor current can be calculated as follows: Input Capacitor A minimum 1F ceramic is recommended on the VIN pin for bypassing. X5R or X7R dielectrics are recommended for the input capacitor. Y5V dielectrics loose most of their capacitance over temperature and are therefore, not recommended. A minimum 1F is recommended for placement close to the VIN and PGND pins for high frequency filtering. Smaller case size capacitors are recommended due to their lower ESR and ESL. Please refer to layout recommendations for proper layout of the input capacitor. Output Capacitor Even though the MIC2225 is optimized for a 2.2F output capacitor, output capacitance can be varied from 1F to 10F. The MIC2225 utilizes Type III internal compensation and utilizes an internal high frequency zero to compensate for the double pole roll off of the LC filter. For this reason, larger output capacitors can create instabilities. X5R or X7R dielectrics are recommended for the output capacitor. Y5V dielectrics lose most of their capacitance over temperature and are therefore, February 2008 IPK = IOUT 12 V VOUT 1 - OUT VIN + 2x f xL M9999-022008-D Micrel, Inc. MIC2225 PCB Layout Recommendations Top Layer Bottom Layer Note: The above figures demonstrate the recommended layout for the MIC2225 fixed output option. February 2008 13 M9999-022008-D Micrel, Inc. MIC2225 8 R1 10k 1 2 JP1 1X2 L1 0.47H / 2.2H MIC2225 J1 VIN 5.5V Max J7 ENLDO J6 EN C1 2.2F/ 6.3V R2 10k C2 0.1F/ 6.3V J2 GND VIN SW 9 4 AVIN FB 5 6 EN 7 ENLDO LDO 2 3 BIAS PGND AGND 10 R3 0 C3 2.2F/ 6.3V J3 VO1 C4 2.2F/ 6.3V J4 VO2 J5 GND 1 Schematic Diagram Bill of Materials Item C1 C2 Part Number C1608X5R0J225K VJ0402Y104KXQCW1BC Manufacturer TDK (1) Vishay Vitramon 2.2F/6.3V, X5R 1 2.2F/6.3V, X5R 1 (2) 10k, 0603, 1/16W, 1% 1 (2) 10k, 0603, 1/16W, 1% 1 0, 0805, 1/8W, 1% 1 2.2H, 1.1A (Isat) 1 2Mhz PWM Synchronous Buck Regulator with 300mA LDO 1 TDK C1608X5R0J225K TDK(1) Vishay Dale R2 CRCW06031002FKEYE3 Vishay Dale R3 CRCW08050000FKEYE3 Vishay Dale(2) U1 CDRH2D11/HPNP-2R2NC MIC2225-XYMT 1 1 C1608X5R0J225K L1 2.2F/6.3V, X5R 0.1F/6.3V, X7R C4 CRCW06031002FKEYE3 Qty. (1) C3 R1 (2) Description Sumida (3) (4) Micrel, Inc. Notes: 1. TDK: www.tdk.com 2. Vishay: www.vishay.com 3. Sumida: www.sumida.com 4. Micrel, Inc.: www.micrel.com February 2008 14 M9999-022008-D Micrel, Inc. MIC2225 Package Information 10-Pin Thin MLF(R) (MT) MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com The information furnished by Micrel in this data sheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer. Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser's use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser's own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. (c) 2007 Micrel, Incorporated. February 2008 15 M9999-022008-D