l6911b STMicroelectronics, l6911b Datasheet - Page 3

• Manufacturer Part Number: l6911b
• Description: 5 Bit Programmable Power Supply Controller For Pentium Ii Processor
• Manufacturer: STMicroelectronics

PIN CONNECTION
PIN FUNCTIONS
4 - 8
N
10
11
12
13
14
15
16
17
18
19
1
2
3
9
PGOOD
VID0 - 4
OCSET
PHASE
UGATE
LGATE
COMP
PGND
Name
VSEN
BOOT
GND
VCC
OVP
SS
FB
Connected to the output voltage is able to manage overvoltage conditions and the PGOOD
signal.
A resistor connected from this pin and the upper Mos Drain sets the current limit protection.
The internal 200 A current generator sinks a current from the drain through the external
resistor. The overcurrent threshold is due to the following equation:
The soft start time is programmed connecting an external capacitor from this pin and GND.
The internal current generator forces through the capacitor 10 A. This pin can be used to
disable the device forcing a voltage lower than 0.4V.
Voltage Identification code pins. These input are open collector and TTL compatible. Are used
to program the output voltage as specified in Table 1 and to set the overvoltage and
powergood thresholds.
This pin is connected to the error amplifier output and is used to compensate the voltage
control feedback loop.
This pin is connected to the error amplifier inverting input and is used to compensate the
voltage control feedback loop.
All internal voltage reference are referred to this pin.
This pin is an open collector output and is pulled low if the output voltage is not within 10%
of the programmed voltage. This pin is forced high if the ”11111” VID is set.
This pin is connected to the source of the upper mosfet and provides the return path for the
high side driver. This pin monitors the drop across the upper mosfet for the current limit.
High side gate driver output.
Bootstrap capacitor pin. Through this pin is supplied the high side driver and the upper mosfet.
Power ground pin. This pin has to be connected closely to the low side mosfet source in order
to reduce the noise injection into the device.
This pin is the lower mosfet gate driver output.
Device supply voltage. The operative supply voltage range is 4.5V to 12V.
Do not connect V
Over voltage protection. If the output voltage reach the 15% above the programmed voltage
this pin is driven high and can be used to drive an external SCR that crowbar the supply
voltage.
OCSET
COMP
VSEN
VID0
VID1
VID2
VID3
VID4
SS
FB
IN
to 12V if V
1
2
3
4
5
6
7
8
9
10
CC
D98IN958
is 5V.
I
P
Description
I
20
19
18
17
16
15
14
13
12
11
ocs
Rdson
R
ocs
RT
OVP
VCC
LGATE
PGND
BOOT
UGATE
PHASE
PGOOD
GND
L6911B
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