Datasheet

10
LT1634
1634fb
APPLICATIONS INFORMATION
WUU
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The reverse characteristics of the LT1634 behave like a
resistor in parallel with a Zener diode. This simple, well
behaved characteristic is important to the proper opera-
tion of circuits like Figure 1. The adjustable output voltage
TYPICAL APPLICATIONS
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The LT1634-5 Generates the LTC1448 Dual 12-Bit
DAC’s Reference and Supply Voltage
Reference for Micropower A/D Converter
V
REF
+IN
–IN
GND
8
7
6
5
1
2
3
4
V
CC
CLK
D
OUT
CS/SHDN
LTC1286
V
IN
5V
0.1µF
5V
1634 TA03
18k
LT1634-4.096
µC/µP
SERIAL
INTERFACE
0.1µF
CLK
D
IN
CS/LD
REF
8
7
6
5
1
2
3
4
V
OUTB
V
CC
GND
V
OUTA
LTC1448
7.5V TO 12V
0.1µF
V
OUTB
V
OUTA
1634 TA04
3.48k
LT1634-5
µC/µP
SERIAL
INTERFACE
0.1µF
reference depends upon positive feedback from the
LT1495’s output to start-up and regulate the bias current
for the LT1634.
Figure 1. Adjustable Output Voltage Reference
–
+
LT1495
LT1634-1.25
V
IN
≥ 10.5V
R1
50k TO 1.75M
R2
250k
1634 F01
V
OUT
1.5V TO 10V
R
B
=
V
OUT
– 1.25V
10µA