Pin
Name Description
12
CS
Current sense amplifier input. Connect to the top of the current sense resistor or the drain of the low-sided
MOSFET if RDS(ON) current sensing is used.
13
CSG
Current sense amplifier input. Connect to the bottom of the sense resistor or the source of the low-side MOSFET
if RDS(ON) current sensing is used.
14
15
16
17
PGND Power ground.
LO
Connect to the gate of the low-side synchronous MOSFET through a short, low inductance path.
Locally decouple to PGND using a low ESR/ESL capacitor located as close to the controller as possible.
VCC
VCCX Optional input for an externally supplied VCC. If VCCX > 4.5V, VCCX is internally connected to VCC and the
internal VCC regulator is disabled. If VCCX is unused, it should be connected to ground.
18
HB
High-side driver supply for bootstrap gate drive. Connect to the cathode of the bootstrap diode and the positive
terminal of the bootstrap capacitor. The bootstrap capacitor supplies current to charge the high-side MOSFET
gate and should be placed as close to the controller as possible.
19
20
HO
SW
Connect to the gate of the high-side synchronous MOSFET through a short, low inductance path
Switch node. Connect to the negative terminal of the bootstrap capacitor and the source terminal of the high-
side MOSFET.
EP
EP
Exposed pad. Solder to ground plane.
3
www.national.com
NSC [ National Semiconductor ]
