MIC24420 Datasheet, PDF (3/34 Pages) Micrel Semiconductor – 2.5A Dual Output PWM Synchronous Buck Regulator IC

Micrel, Inc.
MIC24420/MIC24421
Pin Description (Continued)
Pin Number
13
14
15
16
17
18
19
20
21
22
23
24
EP
Pin Name
EN/DLY2
PG2
CS2
PGND2
LSD2
BST2
SW2
VIND2
PVDD
VIN
VIND1
SW1
ePad
Pin Description
Enable/Delay 2 (Input): This pin can be used to disable V_OUT2. When used to disable V_OUT2, this
pin must be pulled down to ground in less than 1µs for proper operation. It is also used for soft-
start of the output. Soft start capacitor range is 4.7nF to 22nF. See Functional Description
section for additional information.
Power Good 2 (Output) Open drain. Device is in the OFF state. i.e. high when output is within
90% of regulation
Current Sense 2 (Input) Place a resistor from SW2 to this pin to program the current limit point
from 0.5A to 2.7A
Power Ground 2 (Input)
Low-side Drive 2 (Output): External low-side N-Channel MOSFET driver. Use 4.5V rated
MOSFETs.
Boost 2 (Input): Provides voltage for high-side internal MOSFET for Channel 2. Connect a
0.01µF capacitor from SW2 to BST2 pin and a diode to PVDD.
Switch Node 2 (Output): Source of internal high-side power MOSFET.
Supply voltage (Input): For the drain of internal high-side power MOSFET 4.5V to 13.2V.
5V VDD input (input): Power connection to the internal MOSFET drivers. Connect to AVDD
through an RC filter
Supply voltage (Input): For the internal 5V linear regulator. 4.5V to 13.2V.
Supply voltage (Input): For the drain of internal high-side power MOSFET 4.5V to 13.2V.
Switch Node 1 (Output): Source of internal high-side power MOSFET.
Exposed thermal pad for package only. Connect to ground. Must make a full connection to the
ground plane to maximize thermal performance of the package.
June 2012
3
M9999-062012-C