Datasheet
Dual, 256-Tap, Volatile, Low-Voltage,
Linear Taper Digital Potentiometer
MAX5392
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Command Byte
Use the command byte to select the destination of the
wiper data. See Table 2.
Command Descriptions
REG A: The data byte writes to register A and the wiper
of potentiometer A moves to the appropriate position.
D[7:0] indicates the position of the wiper. D[7:0] = 00h
moves the wiper to the position closest to LA. D[7:0] = FFh
moves the wiper closest to HA. D[7:0] is 80h following
power-on.
REG B: The data byte writes to register B and the wiper
of potentiometer B moves to the appropriate position.
D[7:0] indicates the position of the wiper. D[7:0] = 00h
moves the wiper to the position closest to LB. D[7:0] = FFh
moves the wiper to the position closest to HB. D[7:0] is
80h following power-on.
REG A and B: The data byte writes to registers A and
B and the wipers of potentiometers A and B move to
the appropriate position. D[7:0] indicates the position
of the wiper. D[7:0] = 00h moves the wipers to the posi-
tion closest to L_. D[7:0] = FFh moves the wipers to the
position closest to H_. D[7:0] is 80h following power-on.
Applications Information
Variable Gain Amplifier
Figure 8 shows a potentiometer adjusting the gain of a
noninverting amplifier. Figure 9 shows a potentiometer
adjusting the gain of an inverting amplifier.
Adjustable Dual Regulator
Figure 10 shows an adjustable dual linear regulator
using a dual potentiometer as two variable resistors.
Table 2. I
2
C Command Byte Summary
Figure 8. Variable Gain Noninverting Amplifier
Figure 9. Variable Gain Inverting Amplifier
Figure 10. Adjustable Dual Linear Regulator
ADDRESS BYTE COMMAND BYTE DATA BYTE
SCL
CYCLE
NUMBER
START (S)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
STOP (P)
A6 A5 A4 A3 A2 A1 A0
W
ACK
(A)
R7 R6 R5 R4 R3 R2 R1 R0
ACK
(A)
D7 D6 D5 D4 D3 D2 D1 D0
ACK
(A)
REG A
0 1 0 1 A2 A1 A0 0 0 0 0 1 0 0 0 1 D7 D6 D5 D4 D3 D2 D1 D0
REG B
0 1 0 1 A2 A1 A0 0 0 0 0 1 0 0 1 0 D7 D6 D5 D4 D3 D2 D1 D0
REG A AND B
0 1 0 1 A2 A1 A0 0 0 0 0 1 0 0 1 1 D7 D6 D5 D4 D3 D2 D1 D0
V
IN
V
OUT
H
L
W
V
IN
V
OUT
H
L
W
V
OUT1
V
OUT2
OUT1
OUT2
SET1
SET2
IN
V+
L
L
H
H
W
W
MAX8866