LM26400Y
Pin Descriptions
Pin
1
2
3
4
5
6
7
8
9
10
11, 12, 13,14
15
16
DAP
Name
FB1
SS1
EN1
AVIN
GND
EN2
SS2
FB2
BST2
SW2
PVIN
SW1
BST1
Die Attach Pad
Description
Feedback pin of Channel 1. Connect FB1 to an external voltage divider to set the
output voltage of Channel 1.
Soft start pin of Channel 1. Connect a capacitor between this pin and ground to
program the start up speed.
Enable control input for Channel 1. Logic high enables operation. Do not allow this
pin to float or be greater than V
IN
+ 0.3V.
Input supply for generating the internal bias used by the entire IC and for generating
the internal bootstrap bias. Needs to be locally bypassed.
Signal and Power ground pin. Kelvin connect the lower resistor of the feedback
voltage divider to this pin for good load regulation.
Enable control input for Channel 2. Logic high enables operation. Do not allow this
pin to float or be greater than V
IN
+ 0.3V.
Soft start pin of Channel 2. Connect a capacitor between this pin and ground to
program the start up speed.
Feedback pin of Channel 2. Connect FB2 to an external voltage divider to set the
output voltage of Channel 2.
Supply rail for the gate drive of Channel 2's NMOS switch. A bootstrap capacitor
should be placed between the BST2 and SW2 pins.
Switch node of Channel 2. Connects to the inductor, catch diode, and bootstrap
capacitor.
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.
Switch node of Channel 1. Connects to the inductor, catch diode, and bootstrap
capacitor.
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.
3
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