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.

The Quad/Dual N-Channel Matched Pair Zero Threshold MOSFETs are matched at the factory using ALD’s exclusive EPAD® CMOS technology to achieve the industry’s lowest threshold voltage of 0.0V with an exceptional range of variation from 0.01V to -0.01V and an offset voltage of just 2mV. These MOSFETS advance the state-of-the-art in small signal transistors with a level of precision that opens the door to micropower technology never before achievable. For example, basic amplifier applications, operating at supply voltages of only 0.20V and power dissipation of less than 1mW are where zero threshold MOSFETs will revolutionize current day analog circuit design.

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.

Ultra-Low Power Zero Threshold MOSFETS with EPAD technology, also serve as an excellent replacement for normally closed relay applications since they are always in the “on” state without power. For amplifier and sensor circuits, they enable long-term power conservation. This offers the industry the ability to design circuits with operating power up to 100 times lower than competitive MOSFETs. In terms of matched threshold voltages, ALD EPAD MOSFETs are vastly more accurate than currently available devices. In addition, a zero threshold MOSFET greatly expands useful operating signal range, enabling rail-to-rail circuit operation for very low voltage analog circuits.

ALD is now offering the possibility with Zero Threshold EPAD MOSFETs devices that enable the operation of delicate sensors from extremely remote locations for sensitive and critical security applications. Even implantable medical devices that must perform in-situ for many years can now be developed to promote longer operational life to avoid invasive surgery for the replacement of these devices.

Analog circuit engineers who design with standard and small signal discrete analog components will find these EPAD MOSFETs useful when developing circuits for a wide range of applications, from computers and peripherals to industrial controls, handheld instrumentation, security and alarm systems and sensor and detection systems. EPAD zero threshold MOSFETs are useful in the design of specific analog circuits such as current mirrors, discrete differential amplifiers, discrete analog multiplexers, buffers, level translators and fail safe circuits, among many others.

Technical Specifications

The designated part numbers are ALD110800/ALD110900, ALD210800/ALD210800A and ALD212900/ALD212900A. They are available as quad and dual devices, in PDIP and SOIC packages, and they feature, as the most salient specification, a Gate Threshold Voltage of 0.0V +/-0.01V @ 1µA.