max5121beee Maxim Integrated Products, Inc., max5121beee Datasheet - Page 11

• Manufacturer Part Number: max5121beee
• Description: 3v/5v, 12-bit, Serial Voltage-output Dacs With Internal Reference
• Manufacturer: Maxim Integrated Products, Inc.

Table 1. Serial-Interface Programming Commands
X = Don’t care
* S0 is a sub-bit and is always zero.
The power-down lockout pin (PDL) disables shutdown
when low. When in shutdown mode, a high-to-low tran-
sition on PDL will wake up the DAC with its output still
set to the state prior to power-down. PDL can also be
used to wake up the device asynchronously.
Pulling PD high places the MAX5120/MAX5121 in shut-
down mode. Pulling PD low will not return the MAX5120/
MAX5121 to normal operation. A high-to-low transition
on PDL or appropriate commands (Table 1) via the seri-
al interface are required to exit power-down.
The MAX5120/MAX5121 3-wire serial interface is com-
patible with SPI, QSPI, PIC16/PIC17 (Figure 4) and
MICROWIRE (Figure 5) interface standards. The 2-byte-
long serial input word contains three control bits, 12 data
bits in MSB-first format and one sub-bit, which is always
zero (Table 2).
The MAX5120/MAX5121’s digital inputs are double
buffered, which allows the user to:
Load the input register without updating the DAC
register;
Update the DAC register with data from the input
register;
Update the input and DAC registers concurrently.
C2
0
0
0
0
1
1
1
1
1
(SPI/QSPI/MICROWIRE/PIC16/PIC17)
+3V/+5V, 12-Bit, Serial Voltage-Output DACs
C1
0
0
1
1
0
0
1
1
1
Serial-Interface Configuration
16-BIT SERIAL WORD
______________________________________________________________________________________
Power-Down Lockout Input
C0
0
1
0
1
1
0
0
1
1
Power-Down Input (PD)
D11 ............... D0
12-Bit DAC Data
12-Bit DAC Data
XXXXXXXXXXXX
XXXXXXXXXXXX
XXXXXXXXXXXX
XXXXXXXXXXXX
XXXXXXXXXXXX
1XXXXXXXXXXX
00XXXXXXXXXX
(PDL)
S0*
0
0
0
0
0
0
0
0
0
No operation.
Load input register; DAC register unchanged.
Simultaneously load input and DAC registers; exit shutdown.
Update DAC register from input register; exit shutdown.
Shutdown DAC (provided PDL = 1)
UPO goes low (default).
UPO goes high.
Mode 1; DOUT clocked out on SCLK’s rising edge.
Mode 0; DOUT clocked out on SCLK’s falling edge (default).
with Internal Reference
Figure 4. SPI/QSPI Interface Connections (PIC16/PIC17)
Figure 5. MICROWIRE Interface Connections
( ): PIC16/PIC17 ONLY
MAX5120
MAX5121
MAX5120
MAX5121
SCLK
SCLK
DIN
DIN
CS
CS
FUNCTION
CPOL = 0, CPHA = 0
CHE = 1, CKP = 0, SMP = 0,
SSPM3–SSPMO = 0001
SK
SO
I/O
MOSI
SCK
I/O
(PIC16/PIC17)
MICROWIRE
SPI/QSPI
PORT
PORT
V
SS
DD
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