Datasheet

MAX503

5V, Low-Power, Parallel-Input,

Voltage-Output, 10-Bit DAC

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PIN FUNCTION

1 D7 input when A0 = A1 = 1, or S1 input when A0 = 0 and A1 = 1. Always set S1 to 0.*

2 D8 input when A0 = A1 = 1, or D0 input when A0 = 0 and A1 = 1.*

3 D9 input when A0 = A1 = 1, or D1 input when A0 = 0 and A1 = 1.*

4 D2 Input Data, or tie to S0 and multiplex when A0 = 1 and A1 = 0.*

______________________________________________________________Pin Description

NAME

D7/ S1

D8/D0

D9/D1

5 D3 D3 Input Data, or tie to S1 and multiplex when A0 = 1 and A1 = 0.*

6 D4 D4 Input Data, or tie to D0 and multiplex when A0 = 1 and A1 = 0.*

7 D5 D5 Input Data, or tie to D1 and multiplex when A0 = 1 and A1 = 0.*

8 A0

Address Line A0. With A1, used to multiplex 4 of 12 data lines to load low (NBL), middle (NBM),

and high (NBH) 4-bit nibbles. (12 bits can also be loaded as 8+4.)

9 A1

Address Line A1. Set A0 = A1 = 0 for NBL and NBM, A0 = 0 and A1 = 1 for NBL, A0 = 1 and A1 =

0 for NBM, or A0 = A1 = 1 for NBH. See Table 2 for complete input latch addressing.

10 WR Write Input (active low). Used with CS to load data into the input latch selected by A0 and A1.

11 CS Chip Select (active low). Enables addressing and writing to this chip from common bus lines.

12 DGND Digital Ground

13 REFIN

Reference Input. Input for the R-2R DAC. Connect an external reference to this pin or a jumper to

REFOUT (pin 18) to use the internal 2.048V reference.

14 AGND Analog Ground

15 CLR Clear (active low). A low on CLR resets the DAC latches to all 0s.

16 LDAC

Load DAC Input (active low). Driving this asynchronous input low transfers the contents of the input

latch to the DAC latch and updates VOUT.

17 REFGND

Reference Ground must be connected to AGND when using the internal reference. Connect to V

to disable the internal reference and save power.

18 REFOUT Reference Output. Output of the internal 2.048V reference. Tie to REFIN to drive the R-2R DAC.

19 V

Negative Power Supply. Usually ground for single-supply or -5V for dual-supply operation.

20 VOUT Voltage Output. Op-amp buffered DAC output.

21 RFB Feedback Pin. Op-amp feedback resistor. Always connect to VOUT.

22 ROFS Offset Resistor Pin. Connect to VOUT for G = 1, to AGND for G = 2, or to REFIN for bipolar output.

23 V

Positive Power Supply (+5V)

24 D6/S0 D6 input when A0 = A1 = 1, or S0 input when A0 = 0 and A1 = 1. Always set S0 to 0.*

* This applies to 4 + 4 + 4 input loading mode. See Table 2 for 8 + 4 input loading mode.