MAX5823 Datasheet, PDF (22/35 Pages) Maxim Integrated Products – Ultra-Small, Octal Channel, 8-/10-/12-Bit Buffered Output DACs with Internal Reference and I2C Interface

MAX5823/MAX5824/MAX5825
Ultra-Small, Octal Channel, 8-/10-/12-Bit Buffered
Output DACs with Internal Reference and I²C Interface
µC
SDA
SCL
MAX5823
MAX5824
MAX5825
SCL
SDA
ADDR0
ADDR1
MAX5823
MAX5824
+5V
MAX5825
SCL
SDA
ADDR0
ADDR1
Figure 8. Typical I²C Application Circuit
START pair or Repeated START condition required, fol-
lowed by the readback transfer with R/W = 1 to indicate
a read and an acknowledge clock from the MAX5823/
MAX5824/MAX5825. The master still has control of the
SCL line but the MAX5823/MAX5824/MAX5825 take over
the SDA line. The final three bytes in the frame contain
the command and register data written in the first transfer
presented for readback, followed by a STOP condition. If
additional bytes beyond those required to readback the
requested data are provided, the MAX5823/MAX5824/
MAX5825 will continue to readback ones.
It is not necessary for the write and read mode transfers
to occur immediately in sequence. I²C transfers involv-
ing other devices do not impact the MAX5823/MAX5824/
MAX5825 readback mode. Toggling between readback
modes is based on the length of the preceding write
mode transfer. Combined format I²C readback operation
is resumed if a write command greater than two bytes
but less than four bytes is supplied. For commands writ-
ten using multiple register write sequences, only the last
command executed is read back. For each command
written, the readback sequence can only be completed
one time; partial and/or multiple attempts to readback
executed in succession will not yield usable data.
I²C Compatibility
The MAX5823/MAX5824/MAX5825 are fully compatible
with existing I²C systems. SCL and SDA are high-imped-
ance inputs; SDA has an open drain which pulls the data
line low to transmit data or ACK pulses. Figure 8 shows a
typical I²C application.
I²C User-Command Register Map
This section lists the user-accessible commands and
registers for the MAX5823/MAX5824/MAX5825.
Table 4 provides detailed information about the Command
Registers.
Maxim Integrated
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