US3007
I/O O.V. upper trip point
I/O O.V. lower trip point
FAULT Output HI
Vsen2 ramping up
Vsen2 ramping down
Io=3mA
4.3
4.2
10
V
V
V
Note 1: Vs refers to the set point voltage given in Table 1.
D4
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
D3
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
D2
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
D1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
D0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
Vs
D4
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
D3
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
D2
D1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
D0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
Vs
1.30
1.35
1.40
1.45
1.50
1.55
1.60
1.65
1.70
1.75
1.80
1.85
1.90
1.95
2.00
2.05
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
2.0
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
3.0
3.1
3.2
3.3
3.4
3.5
Table 1 - Set point voltage vs. VID codes
PIN DESCRIPTIONS
PIN# PIN SYMBOL
Pin Description
7
6
5
4
3
VID0
VID1
VID2
VID3
VID4
LSB input to the DAC that programs the output voltage. This pin is TTL compatible that
realizes a logic “1” as either HI or Open. When left open,his pin is pulled up internally by
a 27kW resistor to 5V supply.
Input to the DAC that programs the output voltage. This pin is TTL compatible that real-
izes a logic “1” as either HI or Open. When left open,his pin is pulled up internally by a
27kW resistor to 5V supply.
Input to the DAC that programs the output voltage. This pin is TTL compatible that real-
izes a logic “1” as either HI or Open. When left open,his pin is pulled up internally by a
27kW resistor to 5V supply.
MSB input to the DAC that programs the output voltage. This pin is TTL compatible that
realizes a logic “1” as either HI or Open. When left open,his pin is pulled up internally by
a 27kW resistor to 5V supply.
This pin selects a range of output voltages for the DAC.When in the LOW state the range
is 1.3V to 2.05V and when it switches to HI state the range is 2.0V to 3.5V. This pin is
TTL compatible that realizes a logic “1” as either HI or Open. When left open,his pin is
pulled up internally by a 27kW resistor to 5V supply.
8
PGOOD
FB1
This pin is an open collector output that switches LO when any of the outputs are outside
of the specified under voltage trip point. It also switches low when Vsen1 pin is more than
10% above the DAC voltage setting.
This pin provides the feedback for the synchronous switching regulator. Typically this pin
can be connected directly to the output of the switching regulator. However, a resistor
divider is recommended to be connected from this pin to vout1 and GND to adjust the
output voltage for any drop in the output voltage that is caused by the trace resistance.
The value of the resistor connected from Vou1 to FB1 must be less than 100W.
21
Rev. 1.8
12/8/00
4-4
UNISEM [ UNISEM ]
