Zero Threshold MOSFET

When choosing a MOSFET, parameters that are focused on by most design engineers intuitively are VDS, VGS, RDS(on), ID, and VGS(th).

• VDS represents the absolute maximum voltage between drain and source
• VGS represents operating driver voltage between gate and source
• RDS(on) represents drain-source on-state resistance
• ID represents the continuous conduction current
• VGS(th) represents the gate threshold voltage

Anyway, note that the current that flows into the Drain (ID) of a MOSFET is related to the Gate-Source Voltage (VGS), the threshold voltage (VTH) and a property called the transconductance(gM) that describes how well it conducts.

Back to the MOSFET parameters, the MOSFET VGS(th) or Gate Threshold Voltage is the voltage between the Gate and Source that is needed to turn on the MOSFET. In other words, if VGS is at least as high as the threshold voltage, the MOSFET turns on.

That's fine! Then what is a Zero Threshold MOSFET?

Advanced Linear Devices Inc (ALD) created an industry breakthrough Zero Threshold MOSFET device introducing a new level of precision in analog design that makes 0.1-Volt circuits possible for the first time.

With this new analog component, the shackle of “threshold turn-on voltage” placed on the circuit design engineer has just been broken.

The operating voltage of a circuit will no longer be limited by the gate threshold voltage or the bipolar turn-on voltage.

Now a simple circuit using this new device can be constructed to operate on as little as a 20mV supply. On more complicated circuits, consisting of many stages stacked on top of each other, a system operating voltage of just 0.2V to 0.45V becomes a reality.

Providing zero threshold MOSFETs for the first time will support the design of analog circuits that operate on less than one microwatt, giving designers the flexibility to extend the maximum signal range of low voltage systems.

Such versatility supports the operation of countless applications from ultra-sensitive, remote sensor arrays to implantable medical devices.

This new device can be classified as both an enhancement mode device when operated above the threshold voltage and a depletion mode MOSFET device when operated at or below threshold voltage.

Now see a sample datasheet https://www.aldinc.com/pdf/ALD110800.pdf