MP1530 – TRIPLE OUTPUT STEP-UP PLUS LINEAR REGULATORS FOR TFT BIAS
PIN FUNCTIONS
QFN
Pin #
1
TSSOP
Pin #
15
Name Description
SW
Step-Up Converter Power Switch Node. Connect an inductor between the input source
and SW, and connect a rectifier from SW to the main output to complete the step-up
converter. SW is the drain of the internal 250mΩ N-Channel MOSFET switch.
Timing Capacitor for Power Supply Soft-Start and Power-On Sequencing. A capacitor
from CT to GND controls the soft-start and sequencing turn-on delay periods. See
Power-On Sequencing and Start Up Timing Diagram.
Regulators Not Ready. During startup
RDY
will be left high. Once the turn-on sequence
is complete, this pin will be pulled low if all FB voltages exceed 80% of their specified
thresholds. After all regulators are turned-on, a fault in any regulator that causes the
2
16
CT
3
1
4
2
5
6
7
8
3
4
5
6
9
7
10
8
11
9
12
10
13
11
respective FB voltage to fall below 80% of its threshold will cause
RDY
to go high after
approximately 15μs. If the fault persists for more than approximately 6ms (for C
CT
=10nF),
the entire chip will shut down. See Fault Sensing and Timer.
Step-Up Converter Feedback Input. FB1 is the inverting input of the internal error
FB1 amplifier. Connect a resistive voltage divider from the output of the step-up converter to
FB1 to set the step-up converter output voltage.
Step-Up Converter Compensation Node. COMP is the output of the error amplifier.
COMP Connect a series RC network to compensate the regulation control loop of the step-up
converter.
Internal Power Input. IN supplies the power to the MP1530. Bypass IN to PGND with a
IN
10μF or greater capacitor.
GND Signal Ground.
Reference Output. REF is the 1.25V reference voltage output. Bypass REF to GND with
REF a 0.1μF or greater capacitor. Connect REF to the low-side resistor of the negative linear
regulator feedback string.
Negative Linear Regulator Feedback Input. Connect the FB2 feedback resistor string
FB2 between GL and REF to set the negative linear regulator output voltage. FB2 regulation
threshold is GND.
Positive Linear Regulator Feedback Input. Connect the FB3 feedback resistor string
FB3 between GH and GND to set the positive linear regulator output voltage. FB3 regulation
threshold is 1.25V.
On/Off Control Input. Drive EN high to turn on the MP1530, drive EN low to turn it off. For
automatic startup, connect EN to IN. Once the MP1530 is turned on, it sequences the
EN
outputs on (See Power-On Sequencing). When turned off, all outputs are immediately
disabled.
Negative Linear Regulator Output. GL is the output of the negative linear regulator. GL
GL can supply up to 20mA to the load. Bypass GL to GND with a 1μF or greater, low-ESR,
ceramic capacitor.
Negative Linear Regulator Input. IN2 is the input of the negative linear regulator. Drive
IN2 IN2 with an inverting charge pump powered from SW. IN2 can go as low as -20V. For
QFN package, connect the exposed pad to IN2 pin.
RDY
MP1530 Rev. 1.41
5/25/2011
www.MonolithicPower.com
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© 2011 MPS. All Rights Reserved.
6
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