Dallas DS1666-050 Audio digital resistor Datasheet

DS1666, DS1666S
DS1666, DS1666S
Audio Digital Resistor
FEATURES
PIN ASSIGNMENT
• 128 position, digitally controlled potentiometer
• Operates from a +5 volts power supply with TTL signal inputs
• Wide analog voltage range of ±5 volts
• Resistive elements are temperature compensated to
±20 percent end to end
• Low–power CMOS
1
14
2
13
VCC
INC
3
12
VB
CS
4
11
VW
GND
5
10
VH
NC
6
9
VL
NC
7
8
NC
14–PIN DIP (300 MIL)
See Mech. Drawings Section
• 14–pin DIP or 16–pin SOIC for surface mount applications
U/D
NC
NC
INC
NC
CS
NC
GND
• Default position on power up sets wiper position at
10%
• Operating temperature range
– –40°C to +85°C; industrial
Resolution/Step
Resistance values Low End High End –3dB Point
DS1666–10 10KΩ
24Ω
152Ω
1.1 MHz
DS1666–50 50KΩ
122Ω
759Ω
200 KHz
DS1666–100100KΩ 243Ω
1.519KΩ 100 KHz
NC
NC
U/D
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
VCC
NC
VB
VW
VH
NC
NC
VL
16–PIN SOIC (300 MIL)
See Mech. Drawings Section
PIN DESCRIPTION
VH
VL
VW
U/D
INC
CS
NC
VCC
GND
VB
–
–
–
–
–
–
–
–
–
–
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 potentiometer 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 resolution 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 potentiometer advances 1% of total resistance for each
3% of scale advanced, providing for precise amplification of low volume signals. The upper half of the potentiometer advances 2% of resistance for every 1% of
scale advanced, providing for the lower resolution gain
required for high volume amplification.
022698 1/7
DS1666, DS1666S
GRAPH OF AUDIO TAPER Figure 1
100
90
80
PERCENT TOTAL RESISTANCE
70
60
1
2
50
40
30
20
3
1
10
0
0
5
10
LOW TERMINAL
15
20
25
30
35
40
45
55
60
65
70
The CS, U/D and INC inputs control the position of the
wiper along the resistor array (Figure 1). When CS is active (low), a high to low transition on the INC will increment or decrement an internal counter depending on the
level of the U/D pin. When the U/D pin is low, the counter
will decrement. When the U/D pin is high, the counter will
increment. The state of the U/D pin can be changed while
CS is active allowing for precise adjustment during calibration. The output of the counter is decoded to set the
position of the wiper. When the CS input transitions to the
high (inactive) level, the value of the counter is stored and
the wiper position is maintained until power (VCC) is lost.
When power is restored, the DS1666 returns to the default setting and positions the wiper to 10 percent. The
value of the end–to–end and end–to–wiper position is indeterminate while VCC is not applied.
The DS1666 has a resistor array that resembles an audio taper potentiometer as shown in Figure 1 1. Since
the taper is not linear, exact resistance values for each
of the 128 positions of the resistor is not specified. However, the end-to-end resistance is specified to be within
±20 percent of the stated resistor value over an industrial temperature range of –40°C to +85°C.
75
80
85
90
95
100
HIGH TERMINAL
% OF ACTIVE DIGITAL TAPS
OPERATION
022698 2/7
50
ANALOG CHARACTERISTICS
End–to–End Resistance Tolerance = ±20 percent
Typical Noise = <120 dB/Hz REF:IV
Temperature Coefficient = ±800 PPM/°C typical
Resistance at tap #74=18% ± 2% of total resistance.
PIN DESCRIPTIONS
VH
The high end of the potentiometer. This
terminal is capable of handling input voltages between ±5 volts.
VL
The Low end of the potentiometer. This
terminal is capable of handling input voltages between ±5 volts.
VW
The wiper terminal of the potentiometer.
The value of the wiper is controlled by the
U/D and the INC pins.
Up/Down
(U/D)
The U/D input controls the direction of the wiper movement when setting
the potentiometer.
Increment
(INC)
Toggling INC will move the potentiometer wiper by either incrementing or decrementing the counter.
Chip Select The device is selected when CS input is
(CS)
low. The current counter value is stored
when CS is returned high.
DS1666, DS1666S
BLOCK DIAGRAM Figure 2
TRANSFER LOGIC
ARRAY
VH
WIPER
POSITION
DECODE
U/D
INC
7 BIT
COUNTER
CS
1 OF 128
VL
VW
MODE SELECTION Figure 3
CS
INC
U/D
MODE
L
H
WIPER UP
L
L
WIPER DOWN
X
STORE WIPER POSITION
H
022698 3/7
DS1666, DS1666S
ABSOLUTE MAXIMUM RATINGS*
Voltage on CS, INC, U/D, and VCC Relative to Ground
Voltage on VH, VL, and VW Relative to Ground
Voltage on VB
Operating Temperature
Storage Temperature
Soldering Temperature
–0.5V to +7.0V
–6.5V to +6.5V
–6.5V to Ground
–40°C to +85°C
–55°C to +125°C
260°C for 10 seconds
* This is a stress rating only and functional operation of the device at these or any other conditions above those
indicated in the operation sections of this specification is not implied. Exposure to absolute maximum rating
conditions for extended periods of time may affect reliability.
(–40°C to +85°C)
RECOMMENDED DC OPERATING CONDITIONS
PARAMETER
SYMBOL
MIN
TYP
MAX
UNITS
NOTES
Supply Voltage
VCC
+4.5
5.0
5.5
V
1
Input Logic 1
VIH
2.0
VCC+0.5
V
1
Input Logic 0
VIL
–0.5
+0.8
V
1
VH, VL, VW Voltage
VR
VB–0.3
VCC+0.3
V
1
VB Voltage
VB
–5.5
GND
V
1
(–40°C to +85°C; VCC = 5.0V ± 10%)
DC ELECTRICAL CHARACTERISTICS
PARAMETER
SYMBOL
Supply Current
ICC
Input Leakage
ILI
Wiper Resistance
RW
Wiper Current
IW
MIN
TYP
0.1
–1
350
MAX
UNITS
NOTES
5
mA
3
+1
µA
2
650
Ω
1
mA
(tA = 25°C)
CAPACITANCE
PARAMETER
Capacitance
022698 4/7
3
SYMBOL
CONDITION
TYP
MAX
UNITS
NOTES
CIN
tA=25°C
6
10
pF
2
DS1666, DS1666S
(tA=–40°C to +85°C; VCC=+5V ± 10%)
AC ELECTRICAL CHARACTERISTICS
PARAMETER
SYMBOL
MIN
CS to INC Setup
tCI
100
ns
INC High to U/D Change
tID
100
ns
U/D to INC Setup
tDI
1
µs
INC Low Period
tIL
500
ns
INC High Period
tIH
1
µs
INC Inactive to CS Inactive
tIC
500
ns
tCPH
100
ns
CS Deselect Time
TYP
MAX
UNITS
NOTES
AC TIMING Figure 4
CS
tCPH
tCI
tIL
tIC
tIH
INC
tID
tDI
U/D
tIW
VW
VVH
VVL
NOTES:
1. All voltages are referenced to ground.
2. This parameter is periodically sampled and not 100% tested.
3. Typical values are for tA = 25°C and nominal supply voltages.
4. Wiper output open circuited.
AC TEST CONDITIONS
Input Pulse Levels
Input Rise and Fall Times
Input Level
0V to 3V
10 ns
1.5V
022698 5/7
DS1666, DS1666S
DS1666 ORDERING INFORMATION
ORDERING NUMBER
PACKAGE
OPERATING
TEMPERATURE
VERSION
DS1666–010
14L DIP
–40°C TO +85°C
10KΩ
DS1666–050
14L DIP
–40°C TO +85°C
50KΩ
DS1666–100
14L DIP
–40°C TO +85°C
100KΩ
DS1666S–010
16L SOIC (300 MIL)
–40°C TO +85°C
10KΩ
DS1666S–050
16L SOIC (300 MIL)
–40°C TO +85°C
50KΩ
DS1666S–100
16L SOIC (300 MIL)
–40°C TO +85°C
100KΩ
022698 6/7
DS1666, DS1666S
DATA SHEET REVISION SUMMARY
The following represent the key differences between 07/26/93 and 06/18/97 version of the DS1666 data sheet.
Please review this summary carefully.
1. Remove commercial temp grade reference
2. Add order info table
022698 7/7
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