SMALLBLOCK Low Voltage Blas Stabilizer

• Maintains Stable Bias Current in Various Discrete Bipolar Junction and Field Effect Transistors

• Provides Stable Bias Using a Single Component Without Use of Emitter Ballast and Bypass Components

• Operates Over a Wide Range of Supply Voltages Down to 1.8 Vdc

• Reduces Bias Current Variation Due to Temperature and Unit–to–Unit Parametric Changes

• Consumes
0.5 mW at VCC = 2.75 V

This device provides a reference voltage and acts as a DC feedback element around an external discrete, NPN BJT or N–Channel FET. It allows the external transistor to have its emitter/source directly grounded and still operate with a stable collector/drain DC current. It is primarily intended to stabilize the bias of discrete RF stages operating from a low voltage regulated supply, but can also be used to stabilize the bias current of any linear stage in order to eliminate emitter/source bypassing and achieve tighter bias regulation over temperature and unit variations. This device is intended to replace a circuit of three to six discrete components and is available in a SOT–143 package.

The combination of low supply voltage, low quiescent current drain, and small package make it ideal for portable communications applications such as:

• Cellular Telephones

• Pagers

• PCN/PCS Portables

• PCMCIA RF Modems

• Cordless Phones

• Broadband Transceivers and Other Portable Wireless Products