GENERAL DESCRIPTION

ALD110800A/ALD110800/ALD110900A/ALD110900 are high precision

monolithic quad/dual N-Channel MOSFETs matched at the factory using

ALD’s proven EPAD CMOS technology. These devices are members of

the EPAD® Matched Pair MOSFET Family.

Intended for low voltage small signal applications, the ALD110800/

ALD110900 features Zero-Threshold™ voltage, which reduces or eliminates

input to output voltage level shift, including circuits where the signal

is referenced to GND or V+. This feature greatly reduces output signal

voltage level shift and enhances signal operating range, especially for

very low operating voltage environments. With these zero threshold devices,

an analog circuit with multiple stages can be constructed to operate

at extremely low supply or bias voltage levels. For example, an input

amplifier stage operating at 0.2V supply voltage has been demonstrated.

ALD110800A/ALD110800/ALD110900A/ALD110900 matched pair

MOSFETs are designed for exceptional device electrical characteristics

matching with the threshold voltage set precisely at +0.00V +/-0.01V, featuring

a typical offset voltage of only +/-0.001V (1mV). As these devices

are on the same monolithic chip, they also exhibit excellent tempco tracking

characteristics. They are versatile as design components for a broad

range of analog applications such as basic building blocks for current

sources, differential amplifier input stages, transmission gates, and multiplexer

applications.

Besides matched pair electrical characteristics, each individual MOSFET

also exhibits well controlled parameters, enabling the user to depend on

tight design limits. Even units from different batches and different date

of manufacture have correspondingly well matched characteristics.

These devices are built for minimum offset voltage and differential thermal

response, and they are designed for switching and amplifying applications

in +0.2V to +10V systems where low input bias current, low input

capacitance, and fast switching speed are desired. The VGS(th) of these

devices is set at +0.00V, which classifies them as both enhancement mode

and depletion mode devices. When the gate is set at 0.00V, the drain

current is +1µA @ VDS = 0.1V, which allows a class of circuits with output

voltage level biased at or near input voltage level without voltage level

shift. These devices exhibit well controlled turn-off and sub-threshold

characteristics of standard enhancement mode MOSFETs.

The ALD110800A/ALD110800/ALD110900A/ALD110900 feature high input

impedance (1012Ω) and high DC current gain (>108). A sample calculation

of the DC current gain at a drain current of 3mA and input leakage

current of 30pA at 25°C is 3mA/30pA = 100,000,000. For most applications,

connect the V+ pin to the most positive voltage and the V- and IC

pins to the most negative voltage in the system. All other pins must have

voltages within these voltage limits at all times.

FEATURES

• Precision zero threshold voltage mode

• Nominal RDS(ON) @ VGS = 0.00V of 104KΩ

• Matched MOSFET-to-MOSFET characteristics

• Tight lot-to-lot parametric control

• VGS(th) match (VOS) to 2mV and 10mV max.

• Positive, zero, and negative VGS(th) tempco

• Low input capacitance

• Low input/output leakage currents

APPLICATIONS

• Energy harvesting circuits

• Very low voltage analog and digital circuits

• Zero power fail safe circuits

• Backup battery circuits & power failure detector

• Low level voltage clamp & zero crossing detector

• Source followers and buffers

• Precision current mirrors and current sources

• Capacitives probes and sensor interfaces

• Charge detectors and charge integrators

• Differential amplifier input stage

• High side switches

• Peak detectors and level shifters

• Sample and Hold

• Current multipliers

• Analog switches / multiplexers

• Voltage comparators and level shifters