TLV5623C, TLV5623I

2.7V TO 5.5V LOW POWER 8BIT DIGITALTOANALOG

CONVERTERS WITH POWER DOWN

SLAS231B − JUNE 1999 − REVISED APRIL 2004

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APPLICATION INFORMATION

general function

The TLV5623 is an 8-bit single supply DAC based on a resistor string architecture. The device consists of a serial

interface, speed and power-down control logic, a reference input buffer, a resistor string, and a rail-to-rail output

buffer.

The output voltage (full scale determined by external reference) is given by:

2REF

CODE

2n

[V]

n = 8 (bits). The 16-bit data word, consisting of control bits and the new DAC value, is illustrated in the data format

section. A power-on reset initially resets the internal latches to a defined state (all bits zero).

serial interface

The device has to be enabled with CS set to low. A falling edge of FS starts shifting the data bit-per-bit (starting

with the MSB) to the internal register on the falling edges of SCLK. After 16 bits have been transferred or FS

rises, the content of the shift register is moved to the DAC latch, which updates the voltage output to the new

level.

The serial interface of the TLV5623 can be used in two basic modes:

Using chip select (four-wire mode), it is possible to have more than one device connected to the serial port of

the data source (DSP or microcontroller). The interface is compatible with the TMS320 family. Figure 15 shows

an example with two TLV5623s connected directly to a TMS320 DSP.

TMS320

DSP

XF0

XF1

FSX

DX

CLKX

TLV5623

CS FS DIN SCLK

TLV5623

CS FS DIN SCLK

Figure 15. TMS320 Interface