Dual, 128-Tap, Low Voltage Digitally Controlled
Potentiometer (XDCP™)
ISL23328
Features
• Two potentiometers per package
• 128 resistor taps
The ISL23328 is a volatile, low voltage, low noise, low power,
128-Tap, dual digitally controlled potentiometer (DCP) with an
2
I C Bus™ interface. It integrates two DCP cores, wiper switches
• 10kΩ, 50kΩ or 100kΩ total resistance
and control logic on a monolithic CMOS integrated circuit.
2
• I C serial interface
Each digitally controlled potentiometer is implemented with a
combination of resistor elements and CMOS switches. The
position of the wipers are controlled by the user through the I C
- No additional level translator for low bus supply
- Three address pins allow up to eight devices per bus
2
bus interface. Each potentiometer has an associated volatile
Wiper Register (WRi, i = 0, 1) that can be directly written to and
read by the user. The contents of the WRi controls the position
of the wiper. When powered on, the wiper of each DCP will
always commence at mid-scale (64 tap position).
• Power supply
- V = 1.7V to 5.5V analog power supply
CC
2
- V
LOGIC
= 1.2V to 5.5V I C bus/logic power supply
• Maximum supply current without serial bus activity
(standby)
The low voltage, low power consumption, and small package
of the ISL23328 make it an ideal choice for use in battery
- 3µA @ V and V
CC LOGIC
- 1.7µA @ V and V
CC
= 5V
= 1.7V
operated equipment. In addition, the ISL23328 has a V
LOGIC
LOGIC
pin allowing down to 1.2V bus operation, independent from the
• Shutdown Mode
V
value. This allows for low logic levels to be connected
CC
- Forces the DCP into an end-to-end open circuit and RWi is
connected to RLi internally
directly to the ISL23328 without passing through a voltage
level shifter.
- Reduces power consumption by disconnecting the DCP
resistor from the circuit
The DCP can be used as a three-terminal potentiometer or as a
two-terminal variable resistor in a wide variety of applications
including control, parameter adjustments, and signal
processing.
• Wiper resistance: 70Ω typical @ V = 3.3V
CC
• Power-on preset to mid-scale (64 tap position)
• Extended industrial temperature range: -40°C to +125°C
• 14 Ld TSSOP or 16 Ld UTQFN packages
• Pb-free (RoHS Compliant)
Applications
• Power supply margining
• Trimming sensor circuits
• Gain adjustment in battery powered instruments
• RF power amplifier bias compensation
10000
8000
6000
4000
VREF
RH1
-
VREF_M
1 DCP
OF
RW1
+
ISL23328
ISL28114
2000
0
RL1
0
32
64
96
128
TAP POSITION (DECIMAL)
FIGURE 1. FORWARD AND BACKWARD RESISTANCE vs TAP
FIGURE 2. V
ADJUSTMENT
REF
POSITION, 10kΩ DCP
August 19, 2011
FN7902.0
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 |Copyright Intersil Americas Inc. 2011. All Rights Reserved
Intersil (and design) and XDCP are trademarks owned by Intersil Corporation or one of its subsidiaries.
All other trademarks mentioned are the property of their respective owners
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