Datasheet

  
   
SLAS061D − SEPTEMBER 1986 − REVISED JUNE 2007
7
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
PRINCIPLES OF OPERATION
+
−
Output
R
A
= 2 kΩ
(see Note A)
WR
CS
DB0−DB7
V
ref
C (see Note B)
R
B
V
DD
GND
OUT2
OUT1
R
FB
NOTES: A. R
A
and R
B
used only if gain adjustment is required.
B. C phase compensation (10-15 pF) is required when using high-speed amplifiers to prevent
ringing or oscillation.
Figure 3. Unipolar Operation (2-Quadrant Multiplication)
Output
20 kΩ
5 kΩ
10 kΩ
20 kΩ
−
+
+
−
R
FB
OUT1
OUT2
GND
V
DD
R
B
C (see Note B)
V
ref
DB0−DB7
CS
WR
(see Note A)
R
A
= 2 kΩ
NOTES: A. R
A
and R
B
used only if gain adjustment is required.
B. C phase compensation (10-15 pF) is required when using high-speed amplifiers to prevent ringing or oscillation.
Figure 4. Bipolar Operation (4-Quadrant Operation)
Table 1. Unipolar Binary Code Table 2. Bipolar (Offset Binary) Code
DIGITAL INPUT
(see Note 3)
ANALOG OUTPUT
DIGITAL INPUT
(see Note 4)
ANALOG OUTPUT
MSB LSB
ANALOG OUTPUT
MSB LSB
ANALOG OUTPUT
1 1 1 1 1 1 1 1 −V
ref
(255/256) 1 1 1 1 1 1 1 1 V
ref
(127/128)
1 0 0 0 0 0 0 1 −V
ref
(129/256) 1 0 0 0 0 0 0 1 V
ref
(1/128)
1 0 0 0 0 0 0 0 −V
ref
(128/256) = −V
ref
/2 1 0 0 0 0 0 0 0 0
0 1 1 1 1 1 1 1 −V
ref
(127/256) 0 1 1 1 1 1 1 1 −V
ref
(1/128)
0 0 0 0 0 0 0 1 −V
ref
(1/256) 0 0 0 0 0 0 0 1 −V
ref
(127/128)
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 −V
ref
NOTE 3: LSB = 1/256 (V
ref
) NOTE 4: LSB = 1/128 (V
ref
)