MP8200 – LOW VOLTAGE, 1V PRECISION SHUNT VOLTAGE REGULATOR

MP8200 Rev. 0.9

www.MonolithicPower.com

6

9/30/2009

MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.

© 2009 MPS. All Rights Reserved.

APPLICATION INFORMATION

External Bias Resistor

In the case of shunt voltage references, an

between the supply voltage and the MP8200.

through the load and the IC.

should be chosen such that is it small enough

to supply the minimum current to the MP8200

when the supply voltage is at its minimum and

the load current is at its maximum. In addition,

quiescent current does not exceed 10mA when

the supply voltage is at its maximum and the

load current is at its minimum.

Q

L

OUT

SUPPLY

BIAS

I

I

V

V

R

+

−

=

Adjustable Precision Voltage Source

The MP8200 can be combined with a precision

op amp to produce a precise adjustable output

voltage. See Figure 1.

The output of the op amp is determined by the

gain of the circuit using the following equation:

2

R

1

R

1

+

=

An optional capacitor can be added in parallel

with R2 to filter out high frequency noise.

MP8200

MP8200

--

+

1.0V

R1

R2

C2 (Opt.)

Figure 1—Adjustable Precision Voltage

Source

Output Voltage Trim

Using a mechanical or digital potentiometer, the

output voltage of the MP8200 can be trimmed

to ±0.5%. See Figure 2. Note that trimming

other resistor values may not produce an

accurate output from the MP8200.

MP8200

Figure 2—Output Voltage Trim

Precise Negative Voltage Reference

The MP8200 can be configured for use in

applications where a precise negative voltage

reference is needed.

MP8200

R1

-1.0V

+

-

Figure 3—Precise –1.0V Reference

Choose R1 such that 100µA to 10mA is

provided to properly bias the MP8200, using the

equation:

I

V

1

R

DD

=