TLC7226C_15 Datasheet, PDF (9/24 Pages) Texas Instruments – QUADRUPLE 8-BIT DIGITAL-TO-ANALOG CONVERTERS

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TLC7226C, TLC7226I, TLC7226M
QUADRUPLE 8ĆBIT DIGITALĆTOĆANALOG CONVERTERS
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SLAS060F − JANUARY 1995 − REVISED APRIL 2009
PRINCIPLES OF OPERATION
interface logic information (continued)
A0 ¹⁷
To Latch A
A1 ¹⁶
To Latch B
To Latch C
15
WR
To Latch D
Figure 6. Input Control Logic
unipolar output operation
The unipolar output operation is the basic mode of operation for each channel of the TLC7226, with the output
voltages having the same positive polarity as V_ref. The TLC7226 can be operated with a single power supply
(V_SS = AGND) or with positive/negative power supplies. The voltage at V_ref must never be negative with respect
to AGND to prevent parasitic transistor turnon. Connections for the unipolar output operation are shown in
Figure 7. Transfer values are shown in Table 3.
_
REF ⁴
DAC A
+
2
OUTA
_
DAC B
+
1 _OUTB
_
DAC C
+
20
OUTC
_
DAC D
+
19 _OUTD
Figure 7. Unipolar Output Circuit
Table 3. Unipolar Code
DAC LATCH CONTENTS
MSB LSB
1111 1111
1000 0001
1000 0000
0111 1111
0000 0001
ANALOG OUTPUT
ǒ Ǔ ) Vref
255
256
ǒ Ǔ ) Vref
129
256
ǒ Ǔ ) Vref
128
256
+
)
Vref
2
ǒ Ǔ ) Vref
127
256
ǒ Ǔ ) Vref
1
256
0000 0000
0V
ǒ Ǔ ǒ Ǔ NOTE A. 1 LSB +
Vref 2– ⁸
+ Vref
1
256
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