MIC24420 Datasheet, PDF (2/34 Pages) Micrel Semiconductor – 2.5A Dual Output PWM Synchronous Buck Regulator IC

Micrel, Inc.
MIC24420/MIC24421
Ordering Information
Part Number
MIC24420YML
MIC24421YML
Voltage
Adj
Adj
Switching
Frequency
1MHz
500kHz
Temperature Range
-40°C to +125°C
-40°C to +125°C
Package
24-Pin 4mm x 4mm MLF^®
24-Pin 4mm x 4mm MLF^®
Notes:
1. MLF^® is GREEN RoHS compliant package. Lead finish is NiPdAu. Mold compound is Halogen Free.
2. MLF^® z= Pin 1 identifier
Pin Configuration
Lead Finish
Pb-Free
Pb-Free
24-Pin 4mm x 4mm MLF (ML)
Pin Description
Pin Number Pin Name
1
BST1
2
LSD1
3
PGND1
4
CS1
5
PG1
6
EN/DLY1
7
COMP1
8
FB1
9
AVDD
10
AGND
11
FB2
12
COMP2
Pin Description
Boost 1 (Input): Provides voltage for high-side internal MOSFET for channel 1. Connect a
0.01µF capacitor from SW1 to BST1 pin and a diode to PVDD.
Low-side Drive 1 (Output): External low-side N-Channel MOSFET driver. Use 4.5V rated
MOSFETs.
Power Ground 1 (Input).
Current Sense 1 (Input): Place a resistor from SW1 to this pin to program the current limit point
from 0.5A to 2.7A.
Power Good 1 (Output): Open drain. Device is in the OFF state. i.e. high when output is within
90% of regulation.
Enable/Delay 1 (Input): This pin can be used to disable V_OUT1. When used to disable V_OUT1, 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.
Compensation 1 (Input): Pin for external compensation, Channel 1.
Feedback 1 (Input): Input to Ch1 error amplifier. Regulates to 0.7V.
5V Internal Linear Regulator (Output): Connect to an external 4.7µF bypass capacitor. When
V_IN is <6V, this regulator operates in drop-out mode. Connect AVDD to VIN when V_IN <6V.
Analog Ground (Input): Control section ground. Connect to PGND.
Feedback 2 (Input): Input to Channel 2 error amplifier. Regulates to 0.7V.
Compensation 2 (Input): Pin for external compensation, Channel 2.
June 2012
2
M9999-062012-C