MCP4461-103E Datasheet, PDF (63/100 Pages) Microchip Technology – 7/8-Bit Quad I2C Digital POT with Nonvolatile Memory

MCP444X/446X
7.2 Data Byte
Only the Read Command and the Write Command
have Data Byte(s).
The Write command concatenates the 8 bits of the
Data Byte with the one data bit (D8) contained in the
Command Byte to form 9 bits of data (D8:D0). The
Command Byte format supports up to 9 bits of data so
that the 8-bit resistor network can be set to Full-Scale
(100h or greater). This allows wiper connections to
Terminal A and to Terminal B. The D9 bit is currently
unused.
7.3 Error Condition
If the four address bits received (AD3:AD0) and the two
command bits received (C1:C0) are a valid
combination, the MCP44XX will Acknowledge the I²C
bus.
If the address bits and command bits are an invalid
combination, then the MCP44XX will Not Acknowledge
the I²C bus.
Once an error condition has occurred, any following
commands are ignored until the I²C bus is reset with a
Start Condition.
7.3.1 ABORTING A TRANSMISSION
A Restart or Stop condition in the expected data bit
position will abort the current command sequence and
data will not be written to the MCP44XX.
TABLE 7-3: COMMANDS
Command Name
Writes
Value in
EEPROM
Operates on Volatile/
Nonvolatile memory
High
Voltage
(V_IHH) on
HVC pin?
Impact on
WiperLock or
Write Protect
Works
when
Wiper is
“locked”?
Write Data
Read Data
Increment Wiper
Decrement Wiper
Yes ⁽¹⁾
—
—
—
Both
Both
Volatile Only
Volatile Only
—
unlocked ⁽¹⁾
No
—
unlocked ⁽¹⁾
No
—
unlocked ⁽¹⁾
No
—
unlocked ⁽¹⁾
No
High Voltage Write Data
Yes
Both
Yes
unchanged
No
High Voltage Read Data
—
Both
Yes
unchanged
Yes
High Voltage Increment Wiper
—
Volatile Only
Yes
unchanged
No
High Voltage Decrement Wiper
Modify Write Protect or WiperLock
Technology (High Voltage) - Enable
Modify Write Protect or WiperLock
Technology (High Voltage) - Disable
—
— ⁽²⁾
Volatile Only
Nonvolatile Only ⁽²⁾
— ⁽³⁾ Nonvolatile Only ⁽³⁾
Yes
unchanged
No
Yes
locked/
Yes
protected ⁽²⁾
Yes
unlocked/
Yes
unprotected ⁽³⁾
Note 1: This command will only complete, if wiper is “unlocked” (WiperLock Technology is Disabled).
2: If the command is executed using address 02h, 03h 08h, or 09h; that corresponding wiper is locked or
if with address 0Fh, then Write Protect is enabled.
3: If the command is executed using with address 02h, 03h 08h, or 09h; that corresponding wiper is unlocked
or if with address 0Fh, then Write Protect is disabled.
© 2010 Microchip Technology Inc.
DS22265A-page 63