MIC2155 Datasheet, PDF (4/33 Pages) Micrel Semiconductor – 2-Phase, Single Output, PWM Synchronous Buck Control IC

Micrel, Inc.
Pin Configuration
MIC2155/2156
BST1
HSD1
SW1
CS1
EN2
SS
HSD2
SW2
N/C
VIN2
VOUT
COMP2
COMP1
EP
FB2
FB1
EA2+
32-Pin MLF^® (ML)
Pin Description
Pin Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Pin Name
BST1
HSD1
SW1
CS1
EN2
SS
COMP1
FB1
DIFFOUT
RMVOUT
RMGND
AGND
AVDD
N/C
SYNC
Pin Function
Boost1 (Input): Provides voltage for high-side MOSFET driver 1. The gate drive
voltage is higher than the source voltage by V_DD minus a diode drop.
High-Side Drive 1 (Output): High current output-driver for external. high-side
MOSFET.
Switch Node 1 (Output): Return for HSD1
Current Sense (Input). Current-limit comparator noninverting input. Current is
sensed across the side 1 low-side FET during the off-time. Current limit is set by
the resistor in series with the CS1 pin.
Enable 2 (Input): Channel 2 enable. Pull high to enable. Pull low to disable.
Soft Start (Input): Controls the turn-on time of the output voltage. Active at
Power-up, Enable, & Current Limit recovery.
Compensation 1 (Input): Output of the internal error amplifier for Channel 1.
Feedback 1 (Input): Negative input to the error amplifier of Channel 1.
Output of remote sense differential amplifier.
Remote VOUT: Connect to Vout at the remote sense point. Input to precision
differential amplifier.
Remote Ground: Connect to Ground at the remote sense point. Input to
precision differential amplifier.
Analog Ground
Analog supply voltage (input). Connect to V_DD through an RC filter network
No Connect
Sync (Input) : Synchronizes switching to an external source. Leave floating when
not used.
May 2009
4
M9999-052709-A
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