OMO ElectronicOMO Electronic
Expand menu
Hello, Sign inMy Account
0 Cart

MAX5432LETA+T

P1-P3P4-P6P7-P9P10-P12P13-P15P16-P18P19-P19
MAX5432–MAX5435
32-Tap, Nonvolatile, I
2
C, Linear, Digital
Potentiometers
10 ______________________________________________________________________________________
Command Byte
Use the command byte to select the destination of the
wiper data (nonvolatile or volatile memory registers)
and swap data between nonvolatile and volatile memo-
ry registers (see Table 2).
Data Byte
The MAX5432–MAX5435 use the first 5 bits (MSBs,
D7–D3) of the data byte to set the position of the wiper.
The last 3 bits (D2, D1, and D0) are don’t care bits (see
Table 2).
Command Descriptions
VREG: The data byte writes to the volatile memory reg-
ister and the wiper position updates with the data in the
volatile memory register.
NVREG: The data byte writes to the nonvolatile memory
register. The wiper position is unchanged.
NVREGxVREG: Data transfers from the nonvolatile
memory register to the volatile memory register (wiper
position updates).
VREGxNVREG: Data transfers from the volatile memory
register into the nonvolatile memory register.
V
DD
I
OL
= 3mA
I
OH
= 0mA
V
OUT
400pF
SDA
Figure 2. Load Circuit
REGISTER ADDRESS BYTE COMMAND BTYE DATA BYTE
123456789101112131415161718192021222324252627
SCL CYCLE
NUMBER
START
A6 A5 A4 A3 A2 A1 A0
N
O
P/
W
A
C
K
C7 C6 C5 C4 C3 C2 C1 C0
A
C
K
D7 D6 D5 D4 D3 D2 D1 D0
A
C
K
STOP
VREG
0101A2A1A00 00010001 D7D6D5D4D3XXX
NVREG
0101A2A1A00 00100001 D7D6D5D4D3XXX
NVREGxVREG
0101A2A1A00 01100001 D7D6D5D4D3XXX
VREGxNVREG
0101A2A1A00 01010001 D7D6D5D4D3XXX
Table 2. Command Byte Summary
SDA
START
CONDITION
SCL
S
STOP
CONDITION
P
Figure 3. Start and Stop Conditions
SDA
SCL
*SEE THE
Ordering Information/Selector Guide
FOR OTHER ADDRESS OPTIONS.
01
A0
MSB LSB
NOP/W ACK
0 1 0* 0*
Figure 4. Slave Address
X = Don’t care.
MAX5432–MAX5435
32-Tap, Nonvolatile, I
2
C, Linear, Digital
Potentiometers
______________________________________________________________________________________ 11
Nonvolatile Memory
The internal EEPROM consists of a 5-bit nonvolatile
register that retains the value written to it before the
device is powered down. The nonvolatile register is
programmed with the zeros at the factory. Wait a mini-
mum of 12ms after writing to NVREG before sending
another command.
Power-Up
Upon power-up, the MAX5432–MAX5435 load the data
stored in the nonvolatile memory register into the
volatile memory register, updating the wiper position
with the data stored in the nonvolatile memory register.
This initialization period takes 20µs.
Standby
The MAX5432–MAX5435 feature a low-power standby
mode. When the device is not being programmed, it
goes into standby mode and current consumption is
typically 0.5µA.
SDA
DATA STABLE,
DATA VALID
CHANGE OF
DATA ALLOWED
SCL
Figure 5. Bit Transfer
1
SCL
START
CONDITION
SDA
289
CLOCK PULSE FOR
ACKNOWLEDGMENT
ACKNOWLEDGE
NOT ACKNOWLEDGE
Figure 6. Acknowledge
S
SLAVE
ADDRESS
0
A
D15
D14 D13
D12
D11 D10
D9
D8
COMMAND BYTE
A
P
ACKNOWLEDGE FROM
MAX5432–MAX5435
ACKNOWLEDGE FROM
MAX5432–MAX5435
NOP/W
COMMAND BYTE IS STORED ON
RECEIPT OF STOP CONDITION
Figure 7. Command Byte Received
S
SLAVE ADDRESS
0
A
D15
D14 D13
D12
D11 D10
D9
D8
COMMAND BYTE
ACKNOWLEDGE FROM
MAX5432–MAX5435
ACKNOWLEDGE FROM
MAX5432–MAX5435
NOP/W
HOW COMMAND BYTE AND DATA BYTE MAP
INTO MAX5432–MAX5435's REGISTERS
A
DATA BYTE
A
P
D7
D6 D5 D4
D3
X
XX
BYTE
1
ACKNOWLEDGE FROM
MAX5432–MAX5435
Figure 8. Command and Single Data Byte Received
MAX5432–MAX5435
32-Tap, Nonvolatile, I
2
C, Linear, Digital
Potentiometers
12 ______________________________________________________________________________________
Applications Information
Use the MAX5432–MAX5435 in applications requiring
digitally controlled adjustable resistance, such as LCD
contrast control (where voltage biasing adjusts the dis-
play contrast), or for programmable filters with
adjustable gain and/or cutoff frequency.
Positive LCD Bias Control
Figures 9 and 10 show an application where the volt-
age-divider or variable resistor is used to make an
adjustable, positive LCD bias voltage. The op-amp pro-
vides buffering and gain to the resistor-divider network
made by the potentiometer (Figure 9) or to a fixed
resistor and a variable resistor (Figure 10).
Programmable Filter
Figure 11 shows the configuration for a 1st-order pro-
grammable filter. The gain of the filter is adjusted by
R2, and the cutoff frequency is adjusted by R3. Use the
following equations to calculate the gain (G) and the
3dB cutoff frequency (f
C
).
Adjustable Voltage Reference
Figure 12 shows the MAX5432/MAX5433 used as the
feedback resistors in an adjustable voltage reference
application. Independently adjust the output voltages of
the MAX6160 from 1.23V to (V
IN
- 0.2V) by changing
the wiper position of the MAX5432/MAX5433.
G
R
R
f
RC
C
=+
=
××
1
1
2
1
23π
V
OUT
30V
5V
W
H
L
MAX5432
MAX5433
Figure 9. Positive LCD Bias Control Using a Voltage-Divider
V
OUT
30V
5V
W
H
L
MAX5432–
MAX5435
Figure 10. Positive LCD Bias Control Using a Variable Resistor
V
OUT
R1
W
H
L
R2
V
IN
R3
H
W
L
C
MAX5432–
MAX5435
Figure 11. Programmable Filter
W
H
L
+5V
GND
V
IN
OUT
ADJ
V
0
REF
V
0
= 1.23V
V
0
= 1.23V
100kΩ
FOR THE MAX5433
50kΩ
FOR THE MAX5432
R
1
R
2
MAX6160
MAX5432
MAX5433
R2(kΩ)
R2(kΩ)
Figure 12. Adjustable Voltage Reference
P1-P3P4-P6P7-P9P10-P12P13-P15P16-P18P19-P19

MAX5432LETA+T

Mfr. #:
Buy MAX5432LETA+T
Manufacturer:
Maxim Integrated
Description:
Digital Potentiometer ICs 32-Tap Nonvolatile I2C Linear
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
T/T Paypal Visa MoneyGram Western Union

Products related to this Datasheet