
DS1666, DS1666S
Audio Digital Resistor
DS1666, DS1666S
022698 1/7
FEATURES
128 position, digitally controlled potentiometer
Operates from a +5 volts power supply with TTL sig-
nal inputs
Wide analog voltage range of
±
5 volts
Resistive elements are temperature compensated to
±
20 percent end to end
Low–power CMOS
14–pin DIP or 16–pin SOIC for surface mount applica-
tions
Default position on power up sets wiper position at
10%
Operating temperature range
– –40
°
C to +85
°
C; industrial
Resolution/Step
Low End High End –3dB Point
24
152
122
759
243
1.519K
100 KHz
Resistance values
DS1666–10 10K
DS1666–50 50K
DS1666–100100K
1.1 MHz
200 KHz
PIN ASSIGNMENT
1
2
3
4
5
6
7
14
13
12
11
10
9
8
NC
U/D
INC
CS
GND
NC
NC
NC
V
CC
V
B
V
W
V
H
V
L
NC
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
U/D
NC
NC
INC
NC
CS
NC
GND
V
CC
NC
V
B
V
W
V
H
NC
NC
V
L
14–PIN DIP (300 MIL)
See Mech. Drawings Section
16–PIN SOIC (300 MIL)
See Mech. Drawings Section
PIN DESCRIPTION
V
H
V
L
V
W
U/D
INC
CS
NC
V
CC
GND
V
B
– High Terminal of Resistor
– Low Terminal of Resistor
– Wiper Terminal of Resistor
– Up/Down Control
– Wiper Movement Control
– Chip Select for Wiper Movement
– No Connection
– +5 Volts
– Ground
– 0 to –5 Volts
DESCRIPTION
The DS1666 is a solid–state potentiometer which is set
to value by digitally controlled resistive elements. The
potentiometer is composed of 127 resistive sections.
Between each resistive section and both ends of the po-
tentiometer are TAP points accessible to the wiper. The
position of the wiper on the resistance array is controlled
by the CS, U/D and INC inputs. The position of the wiper
defaults to the 10% position on power up. The resolu-
tion of the DS1666 is shown in Figure 1.
The DS1666 Digital Audio Resistor is uniquely designed
to provide a potentiometer that is logarithmic rather than
linear across its entire range. The lower half of the po-
tentiometer advances 1% of total resistance for each
3% of scale advanced, providing for precise amplifica-
tion of low volume signals. The upper half of the poten-
tiometer advances 2% of resistance for every 1% of
scale advanced, providing for the lower resolution gain
required for high volume amplification.