FEATURES & BENEFITS
• Extremely low input offset voltages and
extremely low input bias currents
• Extremely low input signal power
• Robust high-temperature operation
• Industry standard pinout
• Rail-to-rail input/output
• Input bias current of 0.01pA at input
offset voltage of 30μV
• No external components
• No internal chopper clocking noise
• No chopper dynamic power dissipation
• Simple and cost effective
• Small package size
• Drive up to 4000pF load capacitance
• Low power dissipation
• Suitable for rugged, temperature-extreme
environments
APPLICATIONS
• Precision cable driver
• Sensor interface circuits
• Unity gain buffer amplifier
• Precision analog cable driver
• Transducer biasing circuits
• Capacitive and charge integration circuits
• Biochemical probe interface
• Signal conditioning
• Portable instruments
• High source impedance electrode

amplifiers
• Precision Sample and Hold amplifiers
• Precision current to voltage converter
• Error correction circuits
• Sensor compensation circuits
• Precision gain amplifiers
• System output level shifter

GENERAL DESCRIPTION
The ALD1732A/ALD1732 is a precision low-cost low-power monolithic
CMOS operational amplifier intended for a broad range of precision applications
requiring exremely low input signal power. Input signal power is the
product of input offset voltage and input bias current, which represents the
minimum required power draw from the signal source in order to drive the
input of the operational amplifier. Input signal power is also a figure of merit
in source loading and its associated error, and is a measure of the basic
signal resolution possible through the operational amplifier for a given signal
source. For certain types of signal sources, signal loading directly translates
into a significant distortion or "interface noise equivalent" term.
Manufactured with Advanced Linear Devices' enhanced EPAD® silicon
gate CMOS process, the ALD1732A/ALD1732 is designed to set a new
standard in low input signal power requirements. The typical input loading
at its input is 0.03 mV offset voltage and 0.01 pA input bias current at 25C,
resulting in 0.0003 fW input signal power draw. This input characteristic
virtually eliminates any loading effects on most types of signal sources,
offering unparalled accuracy and signal integrity and fidelity. The
ALD1732A/ALD1732 is ideally suited for capacitive and high sensitivity,
high impedance signal sources. It is readily suited for +5V single supply (or
±2V to ±5V) systems, with low operating power dissipation, a traditional
strength of CMOS technology. It is offered with industry standard μA741 and
ICL7611 pin configurations.
The ALD1732A/ALD1732 can operate with rail to rail large signal input and
output voltages with relatively high slew rate. The input voltage can be equal
to or exceed the positive and negative supply voltages while the output
voltage can swing close to these supply voltage rails. This feature significantly
reduces the supply overhead voltage required to operate the operational
amplifier and allows numerous analog serial stages to operate in a low
power supply environment. In addition, the device can accommodate mixed
applications where digital and analog circuits may operate off the same
power supply or battery. This device also features rail-to-rail input and
output voltage ranges, tolerance to over-voltage input spikes of 300mV
beyond supply rails, high open loop voltage gain, useful bandwidth of
1.5MHz, slew rate of 2.1V/μs, and low supply current of 0.8mA. Finally, the
output stage can typically drive up to 400pF capacitive loads in the unity gain
mode and up to 4000pF capacitive loads at a gain of 5.
These features make the ALD1732A/ALD1732 a versatile, high precision
operational amplifier that is user friendly and easy to use with virtually no
source loading and zero input-loading induced source errors. Additionally,
robust design and rigorous screening make this device especially suitable
for operation in temperature-extreme environments and rugged conditions.