ALD EPAD MOSFET arrays with control of independent devices
The ALD210800A/ALD210800 Precision N-Channel MOSFET arrays featuring Zero-Threshold™ Voltage establish new industry benchmarks for forward transconductance and output conductance. Designed with ALD’s EPAD™ CMOS technology, the arrays allow circuit designers to build ultra-low supply voltages. The capabilities of the devices are enabled by the following features:
- Zero Gate Threshold Voltage VGS(th) set precisely at +0.00V +/- 0.01V
- VOS (VGS(th) match) to 2mV / 10mV max
- Sub-threshold voltage or nano-power operations
- <100 mV Min. operating voltage
- <1nA Min. operating current
- <1nW Min. operating power
Circuit Design Impact
The independent control of each device in the package will enable each MOSFET to be characterized with different input and output requirements. This further reduces size and weight in systems by shrinking the footprint of discrete MOSFET circuits up to 50 percent.
The arrays can help designers reduce the number of batteries required for mobile devices. The flexibility of the devices is also suited for improving energy efficiency and battery life in medical devices, boosting audio quality in premium headphones and consumer devices, extending operating range for energy harvesting systems or enhancing sensitivity in sensor arrays among multiple other uses.
The arrays are designed to empower designers to build circuits with multiple cascading stages that operate at extremely low supply/bias voltage levels. It’s now possible to build a nanopower input amplifier stage operating at a <0.2V supply voltage.
As an enhanced addition to the family of ALD110800A/ALD110800 EPAD™ Matched Pair MOSFETs, the new ALD210800A/ALD210800 arrays feature the industry’s first Zero-ThresholdTM voltage to enable circuit designs with input/output signals referenced to GND at enhanced operating voltage ranges in ultra-low operating voltage environments. The MOSFETs are designed for exceptional device electrical characteristics matching with the Gate Threshold Voltage VGS(th) set precisely at +0.00V + /- 0.01V, IDS = +10µA @ VDS = 0.1V, featuring a typical offset voltage of only +/- 0.001V (1mV).
Note the drain current IDS(ON) on the y-axis on the following four curves as it goes into the sub-nano-amp range and the gate-source overdrive voltage scale changes [The overdrive voltage is defined as the voltage between transistor gate and source (VGS) in excess of the threshold voltage (VGS(th)) where VGS(th) is defined as the minimum voltage required between gate and source to turn the transistor on (allow it to conduct electricity). Due to this definition, overdrive voltage is also known as "excess gate voltage" or "effective voltage." Overdrive voltage can be found using the simple equation: VOV = VGS - VGS(th)]:
These MOSFETs excel in limited operating voltage applications such as very low level voltage-clamps and normally-on nano-power circuits.
Additionally, the MOSFETs are intended as versatile design components for a broad range of analog applications such as current mirrors, matching circuits, current sources, differential amplifier input stages, transmission gates, and multiplexers.
N-Channel current source application
Cascode current source application
Each individual MOSFET also exhibits tightly controlled manufacturing characteristics, delivering precise design limits from different production batches. They are built for minimum offset voltage and differential thermal response, and they can be used for switching and amplifying applications in +0.1V to +10V (+/- 0.05V to +/-5V) powered systems requiring low input bias current, low input capacitance, and fast switching speed. At VGS > 0.00V, the device exhibits enhancement mode characteristics. At VGS <0.00V the device operates in depletion mode.
For more details see ALD’s website