Rainbow Electronics MAX5155 - Manual (Page 10)

MAX5154/MAX5155
saved, allowing the MAX5154/MAX5155 to recall the
output state prior to entering shutdown when returning
to normal mode. Exit shutdown by recalling the previ-
ous condition or by updating the DAC with new infor-
mation. When returning to normal operation (exiting
shutdown), wait 20µs for output stabilization.
Serial Interface
The MAX5154/MAX5155 3-wire serial interface is com-
patible with both Microwire (Figure 2) and SPI/QSPI
(Figure 3) serial-interface standards. The 16-bit serial
input word consists of an address bit, two control bits,
12 bits of data (MSB to LSB), and one sub bit as shown
in Figure 4. The address and control bits determine the
MAX5154/ MAX5155’s response, as outlined in Table 1.
Low-Power, Dual, 12-Bit Voltage-Output DACs
with Serial Interface
10 ______________________________________________________________________________________
FUNCTION
A0 C1 C0
D11.......................D0
(MSB) (LSB)
0 0 1 12-bit DAC data Load input register A; DAC registers are unchanged.
0 1 1 12-bit DAC data
Load all DAC registers from the shift register
(start up both DACs with new data.).
1 1 0 12-bit DAC data Load input register B; all DAC registers are updated.
0 1 0 12-bit DAC data Load input register A; all DAC registers are updated.
1 0 1 12-bit DAC data Load input register B; DAC registers are unchanged.
0 0 0 1 1 0 x xxxxxxxx Shut down DAC A (provided PDL = 1).
0 0 0 1 0 1 x xxxxxxxx
Update DAC register B from input register B
(start up DAC B with data previously stored in input register B).
0 0 0 0 0 1 x xxxxxxxx
Update DAC register A from input register A
(start up DAC A with data previously stored in input register A).
1 1 1 xxxxxxxxxxxx Shut down both DACs (provided PDL = 1).
1 0 0 xxxxxxxxxxxx
Update both DAC registers from their respective input registers
(start up both DACs with data previously stored in the input registers).
0 0 0 1 1 1 x xxxxxxxx Shut down DAC B (provided PDL = 1).
0 0 0 0 1 0 x xxxxxxxx UPO goes low (default).
0 0 0 0 1 1 x xxxxxxxx UPO goes high.
0 0 0 1 0 0 1 xxxxxxxx Mode 1, DOUT clocked out on SCLK’s rising edge.
0 0 0 1 0 0 0 xxxxxxxx Mode 0, DOUT clocked out on SCLK’s falling edge (default).
0 0 0 0 0 0 x xxxxxxxx No operation (NOP).
Table 1. Serial-Interface Programming Commands
x = Don’t care
Note: D11, D10, D9, and D8 become control bits when A0, C1, and C0 = 0. S0 is a sub bit, always zero.
SCLK
DIN
CS
SK
SO
I/O
MICROWIRE
PORT MAX5154
MAX5155
Figure 2. Connections for Microwire
16-BIT SERIAL WORD
S0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0