MAX534 Datasheet, PDF (9/16 Pages) Maxim Integrated Products – +5V, Low-Power, 8-Bit Quad DAC with Rail-to-Rail Output Buffers

+5V, Low-Power, 8-Bit Quad DAC
with Rail-to-Rail Output Buffers
Table 1. Serial-Interface Programming Commands
12-BIT SERIAL WORD
LDAC
A1
A0
C1
C0 D7 . . . . . . . . D0
FUNCTION
0
0
0
1
8-bit DAC data
1
Load input register A; all DAC outputs unchanged.
0
1
0
1
8-bit DAC data
1
Load input register B; all DAC outputs unchanged.
1
0
0
1
8-bit DAC data
1
Load input register C; all DAC outputs unchanged.
1
1
0
1
8-bit DAC data
1
Load input register D; all DAC outputs unchanged.
0
0
1
1
8-bit DAC data
1
Load input register A; all DAC outputs updated
0
1
1
1
8-bit DAC data
1
Load input register B; all DAC outputs updated
1
0
1
1
8-bit DAC data
1
Load input register C; all DAC outputs updated
1
1
1
1
8-bit DAC data
1
Load input register D; all DAC outputs updated.
Software LDAC commands. Update all DACs from
0
1
0
0
XXXXXXXX
1
their respective input registers. Also bring the part out
of shutdown mode.
1
0
0
0
8-bit DAC data
X
Load all DACs with shift-register data. Also bring the
part out of shutdown mode.
1
1
0
0
XXXXXXXX
X
Software shutdown (provided PDE is high)
0
0
1
0
XXXXXXXX
X
UPO goes low.
0
1
1
0
XXXXXXXX
X
UPO goes high.
0
0
0
0
XXXXXXXX
X
No operation (NOP); shift data in shift registers.
Set DOUT phase—SCLK rising (mode 1). DOUT
1
1
1
0
XXXXXXXX
X
clocked out on rising edge of SCLK. All DACs updated
from their respective input registers.
Set DOUT phase—SCLK falling (mode 0). DOUT
1
0
1
0
XXXXXXXX
X
clocked out on falling edge of SCLK. All DACs up-
dated from their respective registers (default).
Load All DACs with Shift-Register Data
A1 A0 C1 C0 D7 D6 D5 D4 D3 D2 D1 D0
1 00 0
8-Bit Data
(LDAC = X)
When this command is initiated, all four DAC registers
are updated with shift-register data. This command
allows all DACs to be set to any analog value within the
reference range. It can be used to substitute CLR if
code 00 hex is programmed, which clears all DACs.
Software Shutdown
A1 A0 C1 C0 D7 D6 D5 D4 D3 D2 D1 D0
1 1 0 0 xxx xx xxx
(LDAC = X, PDE = H)
This command shuts down all output buffer amplifiers,
reducing supply current to 10µA max.
User-Programmable Output (UPO)
A1
A0
C1
C0
D7
D6
D5
D4
D3
D2
D1
D0
UPO
Output
0 0 1 0 x x x x x x x x Low
0 1 1 0 x x x x x x x x High
(LDAC = X)
This command initiates the user-programmable logic
output for controlling another device across an isolated
interface. Example devices are gain control of an amplifi-
er and a polarity output for a motor speed control.
No Operation (NOP)
A1 A0 C1 C0 D7 D6 D5 D4 D3 D2 D1 D0
0 0 0 0 xxx xx xxx
(LDAC = X)
The NOP command (no operation) allows data to be
shifted through the MAX534 shift register without affect-
ing the input or DAC registers. This is useful in daisy
chaining (also see the Daisy Chaining Devices section).
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