DS4301 Maxim Integrated Products, Inc., DS4301 Datasheet - Page 6

• Manufacturer Part Number: DS4301
• Description: Ds4301 Nonvolatile, 32-position Digital Potentiometer
• Manufacturer: Maxim Integrated Products, Inc.

The DS4301 is a single nonvolatile digital potentiome-
ter. This 32-position linear potentiometer has an end-to-
end resistance of 200kΩ, and operates over a wide
2.4V to 5.5V supply voltage range. The wiper position is
controlled by the three interface pins (U/D, CS, and
INC), and the wiper setting can be stored in EEPROM
on command.
On power-up, once a stable supply voltage of V
has been reached, the stored wiper setting is loaded
from the EEPROM within t
DS4301 wiper control pins become active approximate-
ly t
been reached.
Nonvolatile, 32-Position Digital Potentiometer
Figure 1. Block Diagram
Figure 2. Timing Diagram
6
GND
V
PU
INC
U/D
CS
CC
_____________________________________________________________________
after a stable supply voltage of V
U/D
INC
CS
V
CC
WIPER POSITION
NONVOLATILE
POSITION X
LOGIC UNIT
V IL
CONTROL
MEMORY
t
IW
WIPER NON-STORAGE
t
CI
V
IL
Detailed Description
t
IL
CONDITION
POSITION X + 1
WLT
t
DI
V
V
IH
IL
t
t
IW
. Also on power-up, the
IH
SETTING
WIPER
5-BIT
t
V
IK
IH
t
F
POS 31
POS 0
Power-Up
CC MIN
POSITION X
t
R
t
CPH
CC MIN
has
H
L
W
Adjusting the wiper of the DS4301 involves using the
three control pins (U/D, CS, and INC). See the
Diagram in Figure 2. To enable wiper adjustment, a
high-to-low transition on the CS pin is required. Hold
CS low for the duration of the communication. Doing
this enables the INC pin to change the wiper position.
Set the U/D pin high to increment or low to decrement
the wiper position. The state of the U/D pin should be
set more than t
from high to low. After the CS pin is active low, a high-
to-low transition on the INC pin moves the wiper in the
direction dictated by the U/D pin. Continue to pulse
INC (high to low) until the desired wiper position is
reached. On the last edge, hold the INC line low. With
the desired wiper position set, there are two ways to
proceed. One method terminates communication with-
out allowing the value of the current wiper position to
be written to the EEPROM. This is done by transitioning
the CS signal to the high state before bringing the INC
signal high. As long as the state of the CS pin is high
before the state of the INC pin goes high, the current
wiper setting is not written to EEPROM. Because the
current wiper setting was not stored to the NV memory,
the previously stored wiper setting, not the current
wiper setting, is loaded from memory if power is cycled
to the device
The other method is used to store a new wiper setting
in the EEPROM. This is done by bringing the state of
the INC pin high for a time of t
state of the CS pin high. Once the states of both CS
and INC pins are high, the current wiper setting is
stored in EEPROM after a time of t
t
IC
POSITION X - 1
t
WST
DI
WIPER STORAGE
CONDITION
before the INC signal is transitioned
IC
before bringing the
t
CLP
Wiper Control
WST
. If power is
Timing