MCP4728 Microchip Technology Inc., MCP4728 Datasheet - Page 36

• Manufacturer Part Number: MCP4728
• Description: 12-bit, Quad Digital-to-analog Converter With Eeprom Memory
• Manufacturer: Microchip Technology Inc.

MCP4728
5.6.3
When the device receives this command, it writes the
input data to the DAC input registers sequentially from
the starting channel to channel D, and also writes to
EEPROM sequentially. The starting channel is
determined by the DAC1 and DAC0 bits.
shows the functions of the channel selection bits for the
sequential write command.
When the device is writing EEPROM, the RDY/BSY bit
stays “Low” until the EEPROM write operation is
completed. The state of the RDY/BSY bit flag can be
monitored by a read command or at the RDY/BSY pin.
Any new command received during the EEPROM write
operation (RDY/BSY bit is “Low”) is ignored.
shows an example of the sequential write command.
Updating Analog Outputs:
The analog outputs can be updated by one of the
following events after the falling edge of the
acknowledge clock pulse of the 4th byte.
a.
b.
c.
TABLE 5-2:
DS22187A-page 36
DAC1
Note 1: The UDAC bit can be used effectively to
When the LDAC pin or UDAC bit is “Low”.
If UDAC bit is “High”, bringing down the LDAC
pin to “Low” any time.
By sending the General Call Software Update
command.
0
0
1
1
SEQUENTIAL WRITE COMMAND:
WRITE DAC INPUT REGISTERS
AND EEPROM SEQUENTIALLY
FROM STARTING CHANNEL TO
CHANNEL D
(C2=0, C1=1, C0=0; W1=1, W0=0)
upload the input register to the output
register, but it affects only a selected
channel only, while the LDAC pin and
General Call Software Update command
affect all channels.
DAC0
0
1
0
1
DAC CHANNEL SELECTION
BITS FOR SEQUENTIAL
WRITE COMMAND
Ch. A - Ch. D
Ch. B - Ch. D
Ch. C - Ch. D
Channels
Ch. D
Figure 5-9
Table 5-2
5.6.4
When the device receives this command, it writes the
input data to a selected single DAC input register and
also to its EEPROM. The channel is selected by the
channel selection bits (DAC1 and DAC0). See
Table 4-3
Figure 5-10
command.
Updating Analog Outputs:
The analog outputs can be updated by one of the
following events after the falling edge of the
acknowledge clock pulse of the 4th byte.
a.
b.
c.
Note 1: The UDAC bit can be used effectively to
When the LDAC pin or UDAC bit is “Low”.
If UDAC bit is “High”, bringing down the LDAC
pin to “Low” any time.
By sending the General Call Software Update
command.
for the channel selection bit function.
SINGLE WRITE COMMAND: WRITE
A SINGLE DAC INPUT REGISTER
AND EEPROM
(C2=0, C1=1, C0=0; W1=1, W0=1)
upload the input register to the output
register, but it affects only a selected
channel only, while the LDAC pin and
General Call Software Update command
affect all channels.
shows an example of the single write
© 2009 Microchip Technology Inc.