MA5001 MPOWER | Alldatasheet

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1.5A 1.5MHz Synchronous Buck Converter  GENERAL DESCRIPTION The MA5001 is a monolithic synchronous buck r egulator with a built in internal power MOSFET. It achieves 1.5A continuous output current fix switching frequency with excellent load and line regulation. Current mode operation provides fast transient response and eases of loop stabilization. Fault condition protection includes cycle-by-c ycle current limiting, output short circuit protection and thermal shutdown. In shut down mode the regulator draws less than 1 μA of supply current. Internal soft-start minimizes the inrush supply current at initial startup. The MA5001 requires a minimum number of readily available standard external components. It is available in SOT23-5L and TSOT23-5L package.  FEATURES - 2.5V to 5.5V input voltage range - Up to 1.5A Output Current - 170/130mΩ Internal Power MOSFET Switch - Stable with Low ESR Output Ceramic Capacitors - Up to 95% Efficiency - Less than 1μA Shutdown Current - 1.5Mhz Switching Frequency - Thermal Shutdown Protection - Current limit and short circuit protections. - Output Adjustable from 1V to VIN - Available in SOT23-5L and TSOT23-5L Pb-Free Package - Build-in soft start function - Input UVLO and OVLO protections

 BLOCK DIAGRAM PWM CONTROL LOGIC OSCILLATOR COMP ILIMIT EA REFERENCE and BIAS SOFTSTART UVLO and POR 0.6V P-SWITCH EN FB GND SW VCC ISEN Thermal Shutdown DRIVER  PIN ASSIGNMENT The packages of MA5001 are SOT23-5L and TSOT23-5L ; the pin assignment is given by: Name Description EN Chip Enable pin. Active high. GND Ground Pin. SW Switching Pin VCC VCC Input Pin FB Feedback Pin.

 ORDER/MARKING INFORMATION Order Information (SOT, TSOT) Top Marking (SOT, TSOT) B 1 Y WX  ABSOLUTE MAXIMUM RATINGS (at TA=25°C) Characteristics Symbol Rating Unit VCC pin voltage VIN -0.3 to 7 V SW pin voltage VSW -0.7 to V IN+0.3 V EN, FB pins voltage -0.3 to V IN+0.3 V Continuous Power Dissipation PD ( T J-TA ) / θJA mW Operating Junction Temperature Top -40 to 125 °C Storage Temperature Range -65 to 150 °C Thermal Resistance from Junction to case SOT,TSOT θJC 110 °C/W Thermal Resistance from Junction to ambient SOT,TSOT θJA 250 °C/W Note: θJA is measured with the PCB copper are (need connect to GND of the MA5001) of approximately 1 in2 (Multi-layer).

 ELECTRICAL CHARACTERISTICS (VIN = 5V, VEN = 5V, VOUT = 3.3V, TA = 25°C) Characteristics Symbol Conditions Min Typ Max Units Input Voltage Range V IN 2.5 - 5.5 V Input UVLO UVLO I OUT=0A 1.8 2.2 2.5 V Input OVLO OVLO IOUT=0A - 6.0 - V Quiescent Current I CCQ V FB = 1V - 250 350 μA Shutdown Current I SD V EN = 0V - 0.1 1 μA FB Pin Voltage V FB 0.588 0.6 0.612 V FB Pin Current (Note1) I FB - - ±50 nA Load Regulation 0A < I OUT<1.5A - 0.6 - % Line Regulation 2.5V<V IN<5.5V - 0.3 - %/V EN Pin Voltage High V ENH 1.5 - - V EN Pin Voltage Low V ENL - - 0.4 V EN Pin Leakage Current V EN = 3V - 0.1 1 μA Switching Frequency F OSC 1.1 1.5 1.9 MHz Current Limit C L 1.7 2.2 - A Switching Maximum Duty Dmax - - 100 % Minimum Duty Dmin 0 - - % P-Switch RDS(ON) R DS(ON)-P - 170 - mΩ N-Switch RDS(ON) (Note1) R DS(ON)-N - 130 - mΩ Low Side Discharger - 60 - Ω Thermal Shutdown T SD - 155 - °C Thermal Shutdown Protection hysteresis TSH - 30 - °C Note1: Guaranteed by design.

 APPLICATION CIRCUIT ˰1.8V≦VOUT≦4.4V˱ OFF ON 1.5A GND FB SW EN 10μF VIN VOUT VCC 10μF Vout=0.6x(1+R1/R2) 22P 2.2μH VOUT＝VFB × (1+R1/R2), VFB = 0.6V, R2 suggest 60k~300kΩ ˰1.0V≦VOUT≦1.6V˱ OFF ON 1.5A GND FB SW EN 10μF VIN VOUT VCC 22μF Vout=0.6x(1+R1/R2) 2.2μH 22μF Layout Guide EN GND SW FB VCC VOUT SW should be connected to Inductor by wide and short trace, keep sensitive components away from this trace MA5001 123 C1's ground must be as closer to IC's GND pin as possible REN C2's ground must be as closer to IC's GND pin as possible CFB VCC GND GND  FUNCTION DESCRIPTION Normal Operation The MA5001 uses a user adjustable frequen cy, current mode, synchronous step-down architecture with internal paver switch. During normal operation, the internal power switch is turned on each cycle when the oscillator se ts the SR latch, and turned off when the comparator resets the SR latch. The peak in ductor current at which comparator resets the SR latch is controlled by the output of error amplifier EA. While the high-side switch is off, the external schottky diode turns on until either the inductor current starts to reverse or the beginning of the next switching cycle.

As the input supply voltage decreases to a value approaching the output voltage, the duty cycle increases toward the maximum on-ti me. Further reduction of the supply voltage forces the high-side switch to remain on fo r more than one cycle until it reaches 100% duty cycle. The output voltage is dropped from the input supply for the voltage which across the high-side switch. Setting the Output Voltage Application circuit item shows the basic applicat ion circuit with adjustable output version. The external resistor sets the output voltage according to the following equation: VOUT=VFB × (1+R1/R2), VFB = 0.6V, R2 suggest 60k~300kΩ Table 1 Resistor select for output voltage setting VOUT R2 R1 1.0V 150K 100K 1.2V 100K 100K 1.5V 100K 150K 1.8V 100K 200K 2.5V 150K 470K 3.3V 100K 450K Over Temperature Protection In most applications the MA5001 does not dissipate much heat due to high efficiency. But, in applications where the MA5001 is r unning at high ambient temperature with low supply voltage and high duty cycles, such as in dropout, the heat dissipated may exceed the maximum junction temperature of the part. If the junction temperature reaches approximately 155°C, the internal high-side power switch will be turned off and the LX node will become high impedance. Over Current Protection The MA5001 cycle-by-cycle limits the peak inductor current to protect embedded switch from damage. Hence the maximum output current (the average of inductor current) is also limited. In case the load increases, the i nductor current is also increase. Whenever the current limit level is reached, the output voltage cannot be regulated and starting to drop. Soft-Start The MA5001 employs internal soft-start circuitry to reduce supply inrush current during startup conditions. When the device exits under-voltage lockout or shut-down mode, the soft-start circuitry will slowly ramp up the output voltage. Short-circuit Protection Short-circuit protection will activate once the feedback voltage falls below, and the operating frequency will be reducing normal swit ching frequency to reduce power delivered from input to output.

 TYPICAL CHARACTERISTICS VIN = 5V, VOUT = 1.8V, ILOAD = No Load VIN = 5V, VOUT = 1.8V, ILOAD = 1.5A Power-on from VIN Ch1=SW , Ch2=VOUT ,Ch3=VIN , Ch4=IOUT Ch1=SW , Ch2=VOUT ,Ch3=VIN , Ch4=IOUT

5V→3.3V @50mA→500mA e 5V→3.3V @500mA→1.5A 5V→2.5V @50mA→500mA 5V→1.8V @50mA→500mA 5V→2.5V @500mA→1.5A 5V→1.8V @500mA→1.5A

5V→1V @50mA→500mA 3.3V→1.8V @50mA→500mA 3.3V→1V @50mA→500mA Ch2=VOUT, Ch4=IOUT 5V→1V @500mA→1.5A 3.3V→1V @500mA→1.5A Ch2=VOUT, Ch4=IOUT

5V→3.3V @1.5A→OCP Auto Recovery Short-circuit Protection 5V →3.3V @0A→SCP Auto Recovery 5V →3.3V @1.5A→SCP Auto Recovery

 Package Outlines (1) SOT23-5L L D b(5x) DETAL A 1(4x) 2(4x) e GAUGE PLANE θ θ θ DETAL A Symbol Dimensions in Millimeters Dimensions in Inches A 1.05 - 1.35 0.041 - 0.053 A1 0.05 - 0.15 0.002 - 0.006 b 0.30 - 0.50 0.012 - 0.020 C 0.08 - 0.22 0.003 - 0.009 L 0.30 - 0.60 0.012 - 0.024 θ 0 o 4 o 8 o 0 o 4 o 8 o θ1 5 o 10 o 15 o 5 o 10 o 15 o θ2 5 o 10 o 15 o 5 o 10 o 15 o

(2) TSOT23-5L e b D y R C θ Symbol Dimensions in Millimeters Dimensions in Inches A1 0.00 - 0.10 0 - 0.004 e 0.95 BSC. 0.037 BSC. e1 1.90 BSC. 0.075 BSC. L1 0.60 REF. 0.024 REF. L2 0.25 BSC. 0.010 BSC. θ 0o - 8 o 0o - 8 o JECED outline: MO-193 AB