 PM6600
Product Page
The new PM6600 is a monolithic white LED driver specifically designed
to supply LED arrays used to backlight mobile PC LCD panels. It
consists of a highly efficient boost converter integrating a Power
MOSFET and six controlled-current generators (ROWs). The device
can manage an output voltage able to supply up to ten white LEDs
per ROW.
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PM6600 functional
description |
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The boost section is based on a constant switching-frequency peak
current-mode architecture. The boost output voltage is controlled
so that the lowest voltage of the ROW, referred to as SGND, is equal
to an internal reference voltage (400 mV typ.). The typical input
voltage range is from 4.7 V up to 28 V. In addition, the PM6600
has an internal 5 V LDO (low dropout) regulator that supplies the
internal circuitry of the device and is capable of delivering up
to 40 mA. The input of the LDO is the main input voltage (Vbatt).
The boost-section switching frequency can be externally adjusted
from 200 kHz to 1 MHz; it also has an internal fixed value of 600
kHz (typ.), which eliminates the need for a resistor, an important
feature in minimum component-count applications.
The frequency pin (FSW) can also be used as the synchronization
input, allowing the PM6600 to operate both as the master or the
slave. The generators can be externally programmed to sink from
16 mA up to 30 mA and can be dimmed via a PWM signal (1 % dimming
duty-cycle at 20 kHz can be managed). The device is able to detect
and manage the open and shorted LED faults. If some ROWs are not
used, during the startup the device is able to self-detect and automatically
disconnect the ROWs without any fault detection. Output over voltage,
internal Power MOSFET over current and thermal shutdown are provided
as protection.
PM6600 main internal blocks
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Constant frequency peak-current control
Internal Power MOSFET
External sync for multi-device applications
Pulse-skip power-saving mode at light load
Programmable soft-start
Programmable OVP protection
Ceramic output capacitor
6 ROWs with 30 mA max current capability (adj.)
Up to 10 white LEDs per ROW
ROW disable option
±1.5 % current matching between ROWs
LED failure (open and short circuit) detection
Housed in VFQFPN 24L space-saving package
The PM6600 is designed for backlighting in LCD panels for battery/AC
adapter supplied equipment, such as:
Notebook panel backlighting
Ultra-mobile PC-panel backlighting
Tablet PC-panel backlighting |
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Part
number
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outputs
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Main
application |
LED max
capability
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Regulated
voltage
|
Regulated
LDO voltage |
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2 |
Mobile PC LCD
backlighting panel |
60 W LEDs
6 ROWs x 10
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Up to 36 V |
5 V |
Part
number
|
LDO
current
|
IC supply
voltage |
ROW current
range
|
Package
|
|
40 mA |
4.7 V to 28 V |
16 to 30 mA
|
VFQFPN
24 pin 4X4
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