Robert L. Chao, founder, President and CEO of Advanced Linear Devices, Inc (ALD), is a talented innovator. Chao’s latest improvement in zero-threshold precision MOSFET technology will enable designers to build better current sources, current mirrors, and oscillator circuits using precision P-channel, zero-threshold MOSFETs. These types of circuits are an important part of Energy Harvesting and IoT sensing architectures, especially since they will have precision coupled with low power drain which is needed for modern sensor detection architectures.
A low voltage current source mirror example
Designs for 0.5% precision, low tempco, cascode current sources
The ALD310700A/ALD310700 quad, zero-threshold MOSFET is especially useful for circuit designers in their development of small signal precision applications utilizing 0.00V Zero Threshold Voltage. The circuit is well-suited for designs requiring very low operating voltages of less than +0.5V power supplies. By allowing circuits to operate in the subthreshold region for the first time ever, the MOSFET’s operating range is expanding into never-before achieved signal levels.
The new MOSFET simplifies circuit biasing schemes and reduces component count while providing greater precision and sensitivity of sensor applications for IoT engineers. The P-Channel MOSFET can work in conjunction with the ALD N-Channel Zero Threshold MOSFET devices in matched sensor applications. The ALD310700A/ALD310700 is the P-channel version of the popular ALD110800A/ALD110800 Precision Zero Threshold N-channel device. Together, these two MOSFET series deliver complementary precision performance. These complementary paired devices enable the design of 0.5% precision current mirrors, current sources, and circuits referenced to power or ground sources including differential amplifier input stages, transmission gates and multiplexers.
Here are some of the features that I really like for circuit designers:
- Precision offset voltages (VOS): 2mV max.; 10mV max.
- Low minimum operating voltage of less than 0.2V
- Ultra-low minimum operating current of less than 1nA
- Matched and tracked temperature characteristics
It is amazing that these devices now operate at a point 100 times lower power than comparable MOSFET arrays. Now circuit designers working on IoT nodes that require matched sensor activity, have a circuit design that can collect power from supercapacitors or deep cycle batteries.
Another good example of where these components will excel is in some potential energy harvesting sources, such as thermal electric generators that yield just 0.2V, and produce such low levels of energy that they are barely useful for driving power in electronic circuitry. These MOSFET arrays can be coupled with a low voltage step-up converter to give low-level power sources a greater range as an energy harvesting source.
This device is available in a quad version and is a member of the EPAD Matched Pair MOSFET Family. Prices start at $2.00 at 100 pieces.