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