RT9224C
Functional Pin Description
Pin No. Pin Name
1
VSEN
Preliminary
Pin Function
Output voltage monitoring input for OVP & PGOOD
Over current set pin, sinks 200µA through a resistor (R
OCS
) from this pin to upper
N-MOSFET to set the trip point:
2
OCSET
I
PEAK
=
200uA
×
R
OCS
MOSFET - on resistance
An over-current trip cycles the soft-start function
3
4
5
6
7
8
9,20
10
11
12
13
14
15
16
17
18
19
SS
VID0
VID1
VID2
VID3
VID4
NC
FB
GND
PGOOD
PHASE
UGATE
BOOT
PGND
LGATE
VCC
OVP
Soft start speed is set by internal 10µA current source and capacitor from this pin to GND
Switching regulator output voltage setting
Switching regulator output voltage setting
Switching regulator output voltage setting
Switching regulator output voltage setting
Switching regulator output voltage setting
No connection
Feedback input pin
IC signal ground
Open drain logic output
This pin is pulled low when the converter output is not within ±10% of the DACOUT
reference voltage
Current limit sense input
High side driver output
Driver power
Low side driver GND
Low side driver output
Power supply input
Over voltage protection
This pin is pulled high when the VSEN voltage is over 15% of the DACOUT reference
voltage
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DS9224C-02 March 2004