Datasheet
MCP4706/4716/4726
DS22272C-page 52 © 2011-2012 Microchip Technology Inc.
6.3 Write All Memory
(C2:C0 = 011)
This Write command is used to update the volatile and
nonvolatile (EEPROM) DAC register value and
Configuration bits. Figure 6-3 shows an example of this
Write command.
•V
OUT
update: At the falling edge of the
Acknowledge pulse of the 4th byte.
• EEPROM update: At the falling edge of the
Acknowledge pulse of the 4th byte.
The DAC register and Power-down Configuration bits
(volatile and EEPROM) are updated with the written
date at the completion of the ACK bit (falling edge of
SCL). The EEPROM memory requires time (T
WC
) for
the values to be written. Another Write All Memory
command should not be issued until the EEPROM
write is complete.
Write commands which only update volatile memory
(C2:C0 = 00x or ‘010’) can be issued. Read
commands and the General Call commands may not
be issued.
FIGURE 6-3: Write All Memory Command.
Note: RDY/BSY bit toggles to “low” and back to
“high” after the EEPROM write is
completed. The state of the RDY/BSY bit
can be monitored by a Read command.
Device Addressing Data bits (8 bits) (3rd byte)
Note 1: The device updates V
OUT
at the falling edge of the SCL at the end of this ACK pulse.
Note 1
2:
The 2nd-4th bytes can be repeated after the 4th byte by continued clocking before issuing Stop bit.
Command
3: ACK bit generated by MCP47X6.
Note 2
b15 b14 b13 b12 b11 b10 b09 b08 b07 b06 b05 b04 b03 b02 b01 b00
MCP4726 D11 D10 D09 D08 D07 D06 D05 D04 D03 D02 D01 D00 X X X X
MCP4716 D09 D08 D07 D06 D05 D04 D03 D02 D01 D00 X X X X X X
MCP4706 D07 D06 D05 D04 D03 D02 D01 D00 X X X X X X X X
SDA
SCL
A2 A1 A01100 0001 PD1 PD0 G 0 b15 b14 b13 b12 b11 b10 b09 b08 0
Ref.
Data bits (16 bits) (3rd + 4th bytes)
Start bit ACK bit
(3)
Read/Write bit (Write)
Stop bit
S
AR/W A A
Power-
bits Down
bits
ACK bit
(3)
ACK bit
(3)
Legend: X = don’t care
D11:D00 = 12-bit data for MCP4726 device
D09:D00 = 10-bit data for MCP4716 device
D07:D00 = 8-bit data for MCP4706 device
1
VREF1 VREF0
Data bits (8 bits) (4th byte)
b07 b06 b05 b04 b03 b02 b01 b00 0
A P
ACK bit
(3)
Voltage
Select
bits
Gain
bit