MP4462 – 3.5A, 4MHz, 36V STEP-DOWN CONVERTER
PIN FUNCTIONS
SOIC QFN
Pin # Pin #
Name Description
Switch Node. This is the output from the high-side switch. A low forward drop Schottky
diode to ground is required. The diode must be close to the SW pins to reduce
switching spikes.
1
1, 2
SW
Enable Input. Pulling this pin below the specified threshold shuts the chip down. Pulling
it up above the specified threshold or leaving it floating enables the chip.
2
3
3
4
EN
Compensation. This node is the output of the error amplifier. Control loop frequency
compensation is applied to this pin.
COMP
Feedback. This is the input to the error amplifier. The output voltage is set by a resistive
divider connected between the output and GND which scales down VOUT equal to the
internal +0.8V reference.
4
5
FB
GND Ground. It should be connected as close as possible to the output capacitor to shorten
Exposed the high current switch paths. Connect exposed pad to GND plane for optimal thermal
5
6
7
8
6
7
Pad
performance.
Switching Frequency Program Input. Connect a resistor from this pin to ground to set
the switching frequency.
FREQ
Input Supply. This supplies power to all the internal control circuitry, both BS regulators
and the high-side switch. A decoupling capacitor to ground must be placed close to this
pin to minimize switching spikes.
8, 9
10
VIN
Bootstrap. This is the positive power supply for the internal floating high-side MOSFET
driver. Connect a bypass capacitor between this pin and SW pin.
BST
MP4462 Rev. 1.02
3/4/2013
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