Pin Descriptions
Pin
Name
Description
Feedback pin of Channel 1. Connect FB1 to an external voltage divider to set the
output voltage of Channel 1.
1
FB1
Soft start pin of Channel 1. Connect a capacitor between this pin and ground to
program the start up speed.
2
SS1
EN1
Enable control input for Channel 1. Logic high enables operation. Do not allow this
pin to float or be greater than VIN + 0.3V.
3
Input supply for generating the internal bias used by the entire IC and for generating
the internal bootstrap bias. Needs to be locally bypassed.
4
AVIN
GND
EN2
Signal and Power ground pin. Kelvin connect the lower resistor of the feedback
voltage divider to this pin for good load regulation.
5
Enable control input for Channel 2. Logic high enables operation. Do not allow this
pin to float or be greater than VIN + 0.3V.
6
Soft start pin of Channel 2. Connect a capacitor between this pin and ground to
program the start up speed.
7
SS2
Feedback pin of Channel 2. Connect FB2 to an external voltage divider to set the
output voltage of Channel 2.
8
FB2
Supply rail for the gate drive of Channel 2's NMOS switch. A bootstrap capacitor
should be placed between the BST2 and SW2 pins.
9
BST2
SW2
PVIN
SW1
BST1
Switch node of Channel 2. Connects to the inductor, catch diode, and bootstrap
capacitor.
10
Input voltage of the power supply. Directly connected to the drain of the internal
NMOS switch. Tie these pins together and connect to a local bypass capacitor.
11, 12, 13,14
Switch node of Channel 1. Connects to the inductor, catch diode, and bootstrap
capacitor.
15
16
Supply rail for the gate drive of Channel 1's NMOS switch. A bootstrap capacitor
should be placed between the BST1 and SW1 pins.
Must be connected to system ground for low thermal impedance and low grounding
inductance.
DAP
Die Attach Pad
3
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