Low Voltage Bias Stabilizer with Enable
MDC5001T1
SILICON
SMALLBLOCK
TM
• Maintains Stable Bias Current in N–Type 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 V
CC
= 2.75 V
• Active High Enable is CMOS Compatible
This device provides a reference voltage and acts as a DC feedback ele-
ment around an external discrete, NPN BJT or N–Channel FET. It allows the
external transistor to have its emitter/source directly grounded and still oper-
ate 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. The “ENABLE” polarity nulls internal current,
Enable current, and RF transistor current in “STANDBY.” This device is in-
tended to replace a circuit of three to six discrete components.
The combination of low supply voltage, low quiescent current drain, and
small package make the MDC5001T1 ideal for portable communications ap-
plications such as:
• Cellular Telephones
• Pagers
• PCN/PCS Portables
• GPS Receivers
• PCMCIA RF Modems
• Cordless Phones
• Broadband and Multiband Transceivers and Other Portable Wireless
Products.
INTERNAL CIRCUIT DIAGRAM
1
2
3
INTEGRATED CIRCUIT
6
5
4
SOT-363
CASE 419B–01 STYLE 19
MDC5001T–1/10