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Rainbow Electronics MAX5253 User Manual

Page 11

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Power-Down Lockout (

PDL)

The power-down lockout pin

PDL disables software

shutdown when low. When in shutdown, transitioning
PDL from high to low wakes up the part with the output
set to the state prior to shutdown.

PDL could also be

used to asynchronously wake up the device.

Daisy-Chaining Devices

Any number of MAX5253s can be daisy chained by
connecting the DOUT pin of one device to the DIN pin
of the following device in the chain (Figure 7).

Since the MAX5253’s DOUT pin has an internal active
pull-up, the DOUT sink/source capability determines
the time required to discharge/charge a capacitive
load. Refer to the serial-data-out V

OH

and V

OL

specifi-

cations in the

Electrical Characteristics.

Figure 8 shows an alternate method of connecting sev-
eral MAX5253s. In this configuration, the data bus is
common to all devices; data is not shifted through a
daisy chain. More I/O lines are required in this configu-
ration because a dedicated chip-select input (

CS) is

required for each IC.

MAX5253

+3V, Quad, 12-Bit Voltage-Output DAC

with Serial Interface

______________________________________________________________________________________

11

CS

SCLK

DIN

DOUT

(MODE 1)

MSB FROM
PREVIOUS WRITE

MSB FROM
PREVIOUS WRITE

COMMAND

EXECUTED

9

8

16

1

A0

A1

D0

C1

C0

D11 D10

D9

D6

D5

D4

D3

D2

D1

D8

D7

DOUT

(MODE 0)

A0

A1

D0

A1

C1

C0

D11 D10

D9

D6

D5

D4

D3

D2

D1

D8

D7

A0

A1

D0

A1

C1

C0

D11 D10

D9

D6

D5

D4

D3

D2

D1

D8

D7

DATA PACKET (N)

DATA PACKET (N-1)

DATA PACKET (N)

DATA PACKET (N-1)

DATA PACKET (N)

Figure 5. Serial-Interface Timing Diagram

SCLK

DIN

DOUT

t

CSO

t

CSS

t

CL

t

CH

t

CP

t

DO1

t

CSW

t

CS1

t

DO2

t

CSH

t

DS

t

DH

CS

Figure 6. Detailed Serial-Interface Timing Diagram