products:

Function:
A Driver Amplifier increases the incident signal level a sufficient amount to "drive" the following Power Amplifier. A so-called "driver amp" may also be used as the final amplifier ("PA") in systems with low output power requirements (less than 100 mW).

A driver amplifer differs from a Gain Stage primarily in the output level it is operating at - gain stages most commonly operate in small signal, whereas driver amplifiers often operate nearer to the 1 dB compression point. Driver amplifiers most commonly use conjugate matching, i.e. both input and output are matched for minimum reflection. In some cases, the output impedance match may need to optimized for output power, linearity, or efficiency as opposed to designed for minimum reflection. Due to the higher power levels involved, feedback matching is not commonly used.

Schematic symbol:

Key Specifications Gain (G, S21) Range: 6 - 20 dB Output Power (Pout, P1 dB) Range: +0 to +20 dBm (1 to 100 mW) Output Intercept Point (IP3 out) Range: +10 to +40 dB Match VSWR: 1.5:1 to 3:1 typ. Return Loss: -8 to -15 typ.

 

Discrete Devices:

Bipolar Transistors as Driver Amplifiers

   Output Power comparison for Bipolar Transistors

GaAs FETs as Driver Amplifiers

   Output Power comparison for GaAs FETs

Integrated Circuits:

ICs for RF/uW Driver Amplifiers

   Output Power comparison - RF/uW ICs

ICs for millimeter wave Receivers, Direct Tansmitters, or Upconverting Transmitters

   Output Power comparison - mmw ICs