TLC7225 Datasheet, PDF (13/22 Pages) Texas Instruments – QUADRUPLE 8-BIT DIGITAL-TO-ANALOG CONVERTERS

TLC7225C, TLC7225I
QUADRUPLE 8-BIT DIGITAL-TO-ANALOG CONVERTERS
SLAS109B – OCTOBER 1996 – REVISED FEBRUARY 2001
APPLICATION INFORMATION
AGND bias for direct bipolar-output operation
The TLC7225 can be used in bipolar operation without adding additional external operational amplifiers by
biasing AGND to V_SS as shown in Figure 9. This configuration provides an excellent method for providing a
direct bipolar output with no additional components. The transfer values are shown in Table 4.
5 ^{REFA (Vref = 5 V)} 22 ^{VDD = 10 to 15 V}
TLC7225^†
_
AGND
DAC A
+
6
OUTA
2
Output range
(5 V to – 5 V)
3
VSS
7
DGND
–5 V
† _{Digital inputs omitted for clarity.}
Figure 9. AGND Bias for Direct Bipolar-Output Operation
Table 4. Bipolar (Offset Binary) Code
DAC LATCH CONTENTS
MSB LSB
1111 1111
1000 0001
1000 0000
0111 1111
0000 0001
0000 0000
ANALOG OUTPUT
ǒ Ǔ ) Vref
127
128
ǒ Ǔ ) Vref
1
128
0V
ǒ Ǔ * Vref
1
128
ǒ Ǔ * Vref
127
128
ǒ Ǔ + * –Vref
128
128
Vref
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