Datasheet

Serial Interface
The 3-wire serial interface (SPI/ QSPI/ and MICROWIRE
compatible) used in the MAX5236/MAX5237 allows for
complete control of DAC operations (Figures 4 and 5).
Figures 1 and 2 show the timing for the serial interface.
The serial word consists of 3 control bits followed by 10
data bits (MSB first) and 3 sub-bits as described in
Tables 1, 2, and 3. When the 3 control bits are all zero
or all 1, D9–D6 are used as additional control bits,
allowing for greater DAC functionality.
The digital inputs allow any of the following: loading the
input register(s) without updating the DAC register(s),
updating the DAC register(s) from the input register(s),
or updating the input and DAC register(s) simultane-
ously. The control bits and D9–D6 allow the DACs to
operate independently.
Send the 16-bit data as one 16-bit word (QSPI) or two
8-bit packets (SPI and MICROWIRE), with CS low dur-
ing this period. The control bits and D9–D6 determine
which registers update and the state of the registers
when exiting shutdown. The 3-bit control and D9–D6
determine the following:
• Registers to be updated
• Selection of the power-down modes
MAX5236/MAX5237
Single-Supply 3V/5V, Voltage-Output, Dual,
Precision 10-Bit DACs
______________________________________________________________________________________ 11
CS
SCLK
DIN
COMMAND EXECUTED
9
8
16 (1)
1
C1
C2 S0
C0
D9
D8
D7
D6 D3 D2 D1 D0 S2 S1D5 D4
Figure 1. Serial Interface Timing
CS
SCLK
DIN
t
CSW
t
CS1
t
CSH
t
CSS
t
CSO
t
CH
t
CL
t
CP
t
DS
t
DH
t
LDL
LDAC
t
CSLD
Figure 2. Detailed Serial Interface Timing