MCP4023 Microchip Technology, MCP4023 Datasheet - Page 31

• Manufacturer Part Number: MCP4023
• Description: Low-Cost NV Digital POT with WiperLock Technology
• Manufacturer: Microchip Technology

5.2.2
This mode is achieved by initializing the U/D pin to a
high state (V
CS pin. Subsequent rising edges of the U/D pin
increment the wiper setting toward terminal A. This is
shown in
After the wiper is incremented to the desired position,
the U/D pin should be driven low (V
CS pin is forced to V
EEPROM. Therefore, if the device voltage is lowered
below the RAM retention voltage of the device, once
the device returns to the operating range, the wiper will
be loaded with this wiper setting (stored in the
EEPROM).
FIGURE 5-2:
© 2006 Microchip Technology Inc.
WiperLock™ Technology
Figure
INCREMENT WITH WRITING WIPER
SETTING TO EEPROM
IH
) prior to achieving a low state (V
5-2.
IH
EEPROM
, the wiper value is written to the
Increment with Writing Wiper Setting to EEPROM.
Wiper
U/D
CS
Note: If WiperLock technology enabled, wiper will not move.
IL
V
V
). Then when the
IH
IH
V
IL
X
X
IL
1
) on the
X+1
X
2
X+2
X
3
To ensure that “unexpected” transitions on the U/D pin
do not cause the wiper setting to increment, the U/D pin
should be driven low and the CS pin forced to V
soon as possible (within device specifications) after the
last desired increment occurs.
After the CS pin is driven to V
serial commands are ignored until the EEPROM write
cycle (t
X+3
X
Note:
4
wc
X+4
X
) completes.
The wiper value will not overflow. That is,
once the wiper value equals 0x3F,
subsequent increment commands are
ignored.
t
WC
WiperLock Technology Enable
WiperLock Technology Disable
MCP4021/2/3/4
X+4
5
IH
6
(from V
DS21945E-page 31
V
V
IL
IH
IL
), all other
IH
as