OTA - AS3280D, Dual, Linearizing Diodes, Alfa, SOIC-16

OTA - AS3280D, Dual, Linearizing Diodes, Alfa, SOIC-16

OTA - AS3280D, Dual, Linearizing Diodes, Alfa, SOIC-16 image 1
Click to zoom in
In Stock

The AS3280 is Alfa’s version of the CA3280 IC in an SOIC package. The AS3280D consists of two variable operational amplifiers that are designed to substantially reduce the initial input offset voltage and the offset voltage variation with respect to changes in programming current. This design results in reduced "AGC thump," an objectionable characteristic of many AGC systems. Careful design of critical places of the circuit reduces the amplifier dependence upon thermal and processing variables.

The AS3280D has all the generic characteristics of an operational voltage amplifier except that the forward transfer characteristics is best described by transconductance rather than voltage gain, and the output is current, not voltage. The magnitude of the output current is equal to the product of transconductance and the input voltage. This type of operational transconductance amplifier has since gained wide acceptance as a gateable, gain controlled building block for instrumentation and audio applications, such as linearization of transducer outputs, standardization of widely changing signals for data processing, multiplexing, instrumentation amplifiers operating from the nanopower range to high current and high speed comparators.

The AS3280D is available in a 16-pin SOIC package.


  • Low Initial Input Offset Voltage: 1.8mV (Max)
  • Low Offset Voltage Change vs IABC: <500 µV (Typ)
  • Low Offset Voltage Drift: 5µV/°C
  • Excellent Matching of the Two Amplifiers for All Characteristics
  • Internal Current-Driven Linearizing Diodes Reduce the External Input Current to an Offset Component
  • Flexible Supply Voltage Range: ±2V to ±15V


  • Voltage Controlled Amplifiers
  • Oscillators
  • Multipliers
  • Demodulators
  • Sample and Hold
  • Instrumentation Amplifiers
  • Function Generators
  • Triangle Wave-to-Sine Wave Converters
  • Comparators
  • Audio Preamplifier
Item ID:
Product Measurements by Type
Input Current at ID = 0100 A
Max. Amplifier Bias Current (IABC)10 mA
Max. Common Mode Input Voltage Range13 V
Max. Differential Input Voltage5 V
Max. Linearizing Diode Bias Current, ID5 mA
Max. Output Short Circuit DurationIndefinite
Max. Peak Input Current with Linearizing Diode±ID
Max. Supply Voltage (Between V+ and V-)+36 V
Max. lnput Voltage RangeV+ to V
Min. Common Mode Input Voltage Range-13 V
Min. Input Resistance0.5 MΩ
Min. Noise Voltage (N lABC = 500µА)20 nV/Hz
Typ. Amplifier Bias Voltage1.2 V
Typ. Amplifier Output Leakage Current (lABC = 0, Vo = 0V)0.015 nA
Typ. Amplifier Output Leakage Current (lABC = 0, Vo = 30V)0.15 nA
Typ. Amplifier Supply Current (Per Amplifier)2 mA
Typ. Bandwidth9 MHz
Typ. Channel Separation94 dB
Typ. Common Mode Rejection Ratio100 dB
Typ. Diode Network Supply Current600 µA
Typ. Forward Transconductance (lABC = 1mA)16 mS
Typ. Forward Transconductance (lABC = 50µА)0.8 mS
Typ. Input Bias Current (lABC = 500µА)0.1 µA
Typ. Input Capacitance4.5 pF
Typ. Input Offset Current0.3 µA
Typ. Input Offset Voltage (IABC = 100µA)1.8 mV
Typ. Input Offset Voltage Drift (ABC = 1 µА to 1mA)0.5 mV
Typ. Linearization Diodes Dynamic Impedance700 Ω
Typ. Linearization Diodes Offset Current (ID=10µА)0.5 µA
Typ. Linearization Diodes Offset Current (ID=100µА)10 µA
Typ. Open Loop Total Harmonic Distortion0.4%
Typ. Open Loop Voltage Gain100 kV/V
Typ. Output Capacitance7.5 pF
Typ. Output Resistance63 MΩ
Typ. Peak Output Current Sink (ABC = 5µА)-5 µA
Typ. Peak Output Current Sink (ABC = 500µА)-410 µA
Typ. Peak Output Current Sink and Source450 µA
Typ. Peak Output Current Source (ABC = 5µА)5 µA
Typ. Peak Output Current Source (ABC = 500µА)410 µA
Typ. Peak Output Voltage VOM+ (lABC = 5µА)12.8 V
Typ. Peak Output Voltage VOM+ (lABC = 500µА)12.6 V
Typ. Peak Output Voltage VOM- (lABC = 5µА)-13.5 V
Typ. Peak Output Voltage VOM- (lABC = 500µА)-13.5 V
Typ. Power Supply Rejection Ratio105 dB
Typ. Slew Rate, Open Loop125 V/µs
Packaging Information
Packaging Dimensions0.402 in. × 0.239 in. × 0.063 in.
Weight (Packaging)0.001 lbs.
PDF: DatasheetAll Models

My Project Lists

You must be logged in to add items to a project list.

Specifications, Files, and Documents

PDF: Datasheet Datasheet505.44 KB