MP8792 – 16V, 12A, SYNCHRONOUS STEP-DOWN CONVERTER

MP8792 Rev. 1.0

www.MonolithicPower.com

4

12/2/2019

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PIN FUNCTIONS

Pin #

Name

Description

1

BST

Bootstrap. Connect a capacitor between SW and BST to form a floating supply

across the high-side switch driver.

2

AGND

Analog ground. Select AGND as the control circuit reference point.

3

CS

Current limit. Connect a resistor to ground to set the current limit trip point.

4

MODE

Operation mode selection. Program MODE to select CCM, pulse skip mode, and

the operating switching frequency. See Table 1 on page 14 for additional details.

5

TRK/REF

External tracking voltage input. The output voltage tracks this input signal.

Decouple TRK/REF with a ceramic capacitor as close to the pin as possible. X7R or

X5R grade dielectric ceramic capacitors are recommended for their stable

temperature characteristics. The capacitance determines the soft-start time. See

Equation 2 on page 14 for additional details.

6

VSNS-

Differential remote-sense negative input. Connect VSNS- directly to the negative

side of the voltage sense point. Short to GND if remote sense is not used.

7

FB

Feedback (differential remote-sense positive input). An external resistor divider

from the output to VSNS- (tapped to FB) sets the output voltage. It is recommended

to place the resistor divider as close to FB as possible. Avoid placing vias on the FB

traces.

8

EN

Enable. EN is an input signal that turns the regulator on or off. Drive EN high to turn

the regulator on; drive EN low to turn it off. Connect EN to VIN through a pull-up

resistor or a resistive voltage divider for automatic start-up. Do not float EN.

9

PGOOD

Power good output. This is an open-drain signal. A pull-up resistor connected to a

DC voltage is required to indicate if the output voltage is within regulation. There is a

delay of about 1ms from when the FB voltage becomes greater than or equal to

92.5% of the reference voltage and the time PGOOD pulls high.

10, 21

VIN

Input voltage. VIN supplies power for the internal MOSFET and regulator. Input

capacitors are required to decouple the input rail. Use wide PCB traces to make the

connection.

11

–18

PGND

System ground. PGND is the reference ground of the regulated output voltage, and

it should be considered while designing the PCB layout. Use wide PCB traces to

make the connection.

19

VCC

Internal 3V LDO output. The driver and control circuits are powered from this

voltage. Decouple VCC with a minimum 1µF ceramic capacitor, placed as close to

VCC as possible. X7R or X5R grade dielectric ceramic capacitors are recommended

for their stable temperature characteristics.

20

SW

Switch output. Connect SW to the inductor and bootstrap capacitor. SW is driven up

to VIN by the high-side switch during the on time of the PWM duty cycle. The inductor

current drives SW low during the off time. Use wide PCB traces to make the

connection.