MIC2169A_09 Datasheet, PDF (2/15 Pages) Micrel Semiconductor – 500kHz PWM Synchronous Buck Control IC

MIC2169A
Ordering Information
Part Number
Pb-Free Part Number
MIC2169ABMM
MIC2169AYMM
Frequency
500kHz
Micrel
Junction Temp. Range
–40°C to +125°C
Package
10-lead MSOP
Pin Configuration
VIN 1
VDD 2
CS 3
COMP/EN 4
FB 5
10 BST
9 HSD
8 VSW
7 LSD
6 GND
10-Pin MSOP (MM)
Pin Description
Pin Number
1
2
3
4
5
6
7
8
9
10
Pin Name
VIN
VDD
CS
COMP/EN
FB
GND
LSD
VSW
HSD
BST
Pin Function
Supply Voltage (Input):  3V to 14.5V.
5V Internal Linear Regulator (Output):  V_DD is the external MOSFET gate
drive supply voltage and an internal supply bus for the IC. When V_IN is <5V,
this regulator operates in dropout mode.
Current Sense / Enable (Input):  Current-limit comparator noninverting input.
The current limit is sensed across the MOSFET during the ON time. The cur-
rent can be set by the resistor in series with the CS pin.
Compensation (Input):  Dual function pin. Pin for external compensation.
If this pin is pulled below 0.2V, with the reference fully up the device shuts
down (50µA typical current draw).
Feedback (Input): Input to error amplifier. Regulates error amplifier to 0.8V.
Ground (Return).
Low-Side Drive (Output): High-current driver output for external synchro-
nous MOSFET.
Switch (Return):  High-side MOSFET driver return.
High-Side Drive (Output):  High-current output-driver for the high-side MOS-
FET. When V_IN is between 3.0V to 5V, 2.5V threshold MOSFETs should be
used. At V_IN > 5V, 5V threshold MOSFETs should be used.
Boost (Input):  Provides the drive voltage for the high-side MOSFET driver.
The gate-drive voltage is higher than the source voltage by V_IN minus a
diode drop.
M9999-040609
2
April 2009