MP8201DT-LF-P Monolithic Power Systems (MPS), MP8201DT-LF-P Datasheet - Page 6

• Manufacturer Part Number: MP8201DT-LF-P
• Description: Switching Converters, Regulators & Controllers Prec Adj Shunt Voltage Regulator
• Manufacturer: Monolithic Power Systems (MPS)

Specifications of MP8201DT-LF-P

• Rohs: yes
• Output Voltage: 1.2 V
• Output Power: 0.52 W
• Input Voltage: 1.2 V to 12 V
• Operating Temperature Range: - 40 C to + 85 C
• Mounting Style: SMD/SMT
• Package / Case: SOT-23-3
• Factory Pack Quantity: 500

APPLICATION INFORMATION
External Bias Resistor
In the case of shunt voltage references, an
external
between the supply voltage and the MP8201.
R
through the load and the IC.
The load and the supply voltage can vary, so
R
enough to supply the minimum current to the
MP8201 when the supply voltage is at its
minimum and the load current is at its maximum.
In addition, R
the quiescent current does not exceed 10mA
when the supply voltage is at its maximum and
the load current is at its minimum.
Choose R
Adjustable Precision Voltage Source
The MP8201 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:
An optional capacitor can be added in parallel
with R2 to filter out high frequency noise.
MP8201 Rev. 0.9
9/30/2009
V
BIAS
BIAS
OUT
Figure 1—Adjustable Precision Voltage
sets the current that is required to pass
should be chosen such that is it small
C1
1
BIAS
bias
R2
MP 8101
R
+
-
BIAS
using the following equation:
BIAS
3
4
resistor
needs to be large enough that
V
=
OUT
R1
R
Source
V
BIAS
SUPPLY
MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
=
MP8201 – LOW VOLTAGE, ADJUSTABLE SHUNT VOLTAGE REGULATOR
1
I
L
+
1
V
2
(R
+
CC
R
R
R
−
I
Q
2
MP8201
BIAS
1
B
V
OUT
3
)
is
© 2009 MPS. All Rights Reserved.
required
www.MonolithicPower.com
Output Voltage Trim
Using a mechanical or digital potentiometer, the
output voltage of the MP8201 can be trimmed
to ±0.5%. See Figure 2. Note that trimming
other resistor values may not produce an
accurate output from the MP8200.
Precise Negative Voltage Reference
The MP8201 can be configured for use in
applications where a precise negative voltage
reference is needed.
Choose R1 such that 60µA to 20mA is provided
to properly bias the MP8201, using the equation:
Figure 3—Precise –1.0V Reference
Figure 2—Output Voltage Trim
V
1
2
1
2
V
DD
CC
R
R1
BIAS
3
3
MP8201
R
MP8201
1
=
V
DD
I
V
V
OUT
OUT
6