Advanced Linear Devices ALD212902PAL

The ALD212902 precision enhanced-mode N-channel EPAD MOSFET array is precision-matched at the factory using ALD's proven EPAD CMOS technology. These dual-device components are enhanced versions of the ALD110902 EPAD MOSFET series, featuring higher forward transconductance and output conductance, particularly at ultra-low supply voltages. The ALD212902 is designed for low-voltage, low-power small-signal applications, characterized by a precision +0.20V threshold voltage that enables circuit designs referencing input/output signals to extremely low operating voltage ranges. Using these devices, multi-stage cascaded circuits can be constructed to operate at extremely low supply/bias voltage levels. For example, a micropower input amplifier stage operating at a supply voltage below 0.2V has been successfully built using these devices. The ALD212902 EPAD MOSFET features excellent matched-pair electrical characteristics, with gate threshold voltage VGS(th) precisely set to +0.20V ± 0.010V. At VDS = 0.10V with IDS = +20μA, the typical offset voltage is only ±0.002V (2mV). Built on a monolithic die, these devices also exhibit outstanding temperature tracking characteristics. These precision devices serve as versatile design components for a wide range of analog small-signal applications, including current mirrors, matched circuits, current sources, differential amplifier input stages, transmission gates, and fundamental building blocks for multiplexers. They also excel in limited supply voltage applications such as ultra-low-level voltage clamping and micropower normally-on circuits. In addition to precision matched-pair electrical characteristics, each individual EPAD MOSFET features well-controlled manufacturing characteristics, enabling users to rely on tight design limits across different production lots. These devices are designed for minimum offset voltage and differential thermal response, suitable for switching and amplification applications in +0.1V to +10V (±0.05V to ±5V) supply systems where low input bias current, low input capacitance, and fast switching speed are required. When VGS > +0.20V, the device exhibits enhancement-mode characteristics; when VGS < +0.20V, the device operates in the subthreshold region, exhibiting conventional depletion-mode characteristics with well-controlled cutoff and subthreshold levels, functioning identically to a standard enhancement-mode MOSFET. The ALD212902 features high input impedance (2.5 × 10^10Ω) and high DC current gain (>10^8). At 25°C, with a drain output current of 30mA and an input current of 300pA, an example DC current gain calculation yields 30mA / 300pA = 100,000,000, which corresponds to approximately eight orders of magnitude of dynamic operating current range.

• Precision VGS(th) = +0.20 V ± 0.02 V
• Offset voltage VOS (VGS(th) matching) 10 mV max
• Sub-threshold (micro-power) operation
• Minimum operating voltage < 200mV
• Minimum operating current < 1nA
• Minimum operating power < 1nW
• Operating current range > 100,000,000:1
• High transconductance and output conductance
• Low on-resistance RDS(ON) of 14Ω
• Output current > 50mA
• Matched and tracking temperature coefficients
• Tight lot-to-lot parameter control
• Positive, zero, and negative VGS(th) temperature coefficients
• Low input capacitance and leakage current

• Low-overhead current mirrors and current sources
• Zero-power always-on circuits
• Energy harvesting circuits
• Ultra-low-voltage analog and digital circuits
• Zero-power fail-safe circuits
• Backup battery circuits and power failure detectors
• Ultra-low-level voltage clamps
• Ultra-low-level zero-crossing detectors
• Matched source followers and buffers
• Precision current mirrors and current sources
• Matched capacitive probe and sensor interfaces
• Charge detectors and charge integrators
• High-gain differential amplifier input stages
• Matched peak detectors and level translators
• Multi-channel sample-and-hold switches
• Precision current multipliers
• Discrete matched analog switches/multiplexers
• Micro-power discrete voltage comparators