32-Channel, 14-Bit, Voltage-Output

DACs with Serial Interface

______________________________________________________________________________________

21

Read-Data Format

The MAX5753/MAX5754/MAX5755 support daisy-chain

connections of multiple devices. The default (power-up)

configuration for the MAX5753/MAX5754/MAX5755

assumes that the device may be part of a daisy chain

of devices. DOUT follows DIN after 32 clock cycles. For

a read command, DOUT provides read data (instead of

the data value shifted in) in the next cycle following a

CS rising edge. Figures 5 and 6 show examples of

daisy-chain data sequences.

Shutdown Mode

The MAX5753/MAX5754/MAX5755 feature a software-

controlled low-power shutdown mode. When bit 9 of the

configuration register is a logic high, the analog section

of the device is disabled, and the outputs go high

impedance. In shutdown, supply current is reduced to

50µA. Data stored in the DAC and input registers is

retained, and the device outputs return to their previous

values when the device is brought out of shutdown. The

serial interface remains active while the device is in

shutdown.

Power-Up State

The MAX5753/MAX5754/MAX5755 monitor the four power

supplies and maintain the output buffers in a known state

until sufficient voltage is available to ensure that no output

glitches occur. Once the minimum voltage threshold has

been passed, the device outputs come up in the clear

must be applied first. Power sequencing is not necessary

CONTROLLER

DEVICE

DIN

DOUT

1 OR 0

SCLK

CS

MAX575_

DSP

Figure 7. Stand-Alone Configuration

CONTROLLER

DEVICE

DIN

DOUT

1 OR 0

1 OR 0

1 OR 0

SCLK

CS

MAX575_

DIN

DOUT

SCLK

CS

MAX575_

DIN

DOUT

SCLK

CS

MAX575_

DSP

DSP

DSP

Figure 8. Example of a Parallel Configuration with Read-Back

C1

C2

C0 A5 A4 A3 A2

A1 A0 Sp Sp

Sp Sp Sp Sp Sp D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 S1 S0

D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 S1 S0

DIN(0)

SCLK

CS (

µC)

CS (DSP)

DOUT(0)

OR

Figure 9. Read Data Timing When Not Daisy-Chained