LED7708 Datasheet, PDF (1/53 Pages) STMicroelectronics – Boost controller section

LED7708
16 channels x 85 mA LED driver with boost controller and 4-wire
serial interface
Datasheet —production data
Features
■ Boost controller section
– 3.6 V to 36 V input voltage range (LDO)
– Adaptive output voltage for high efficiency
– Internal +5 V LDO for gate driver supply
– Internal +3.3 V LDO for device supply
– High performance external MOSFET driver
– 250 kHz to 1 MHz switching frequency
– Programmable OV and OC protection
– Fixed frequency peak current-mode control
– External synchronization for multi-device
application
– Overtemperature alert and thermal
shutdown
■ LED array driver section
– 16 channels with 85 mA/ch current
capability
– ±2% channel current accuracy
– ±2% channel-to-channel current matching
– LED short-circuit and open channel fault
detection and management
– 4-wire, 30 MHz serial interface
– 16 x16-bit, 1x256-bit or 1x192-bit serial
data formats
– Grouped or independent channel PWM
control
– Selectable 12/16-bit grayscale brightness
control for local dimming
– Programmable internal dimming oscillator
– Programmable grayscale latency
– Master/slave chain configuration supported
Applications
■ TV and monitor backlight units for LCD panels
■ Medium and large size LCD panel backlights
■ RGB/RGGB backlight solutions
6&1&0.XX,
PITCH
Description
The LED7708 has been specifically designed to
supply several LEDs starting from a single low-
voltage rail. It integrates a boost controller,
sixteen current generators and a 4-wire serial
interface. The boost controller regulates the
output voltage in an adaptive way, according to
the LED requirements, resulting in an improved
overall efficiency. All the current generators are
40 V-rated, allowing the LED7708 to drive several
LEDs in series on each channel. The channels
can be put in parallel for higher output current.
The brightness of the LEDs is controlled by using
the serial interface. A selectable 12-bit or 16-bit
grayscale brightness control allows independent
PWM on each channel. A programmable on-chip
dimming oscillator is provided for external circuitry
simplification. The device has dedicated pins to
lock to an external synchronization with other
devices (master or slave) for noise reduction in
multi-device applications. The LED7708
implements basic protection (OVP, OCP and
thermal shutdown) as well as LED array
protection. It can detect and manage open-LED
and shorted-LED faults and different fault-
management options are available in order to
cover most application needs.
Table 1. Device summary
Order codes
Package
LED7708
LED7708TR
VFQFPN-48 7x7
(exposed pad)
Packing
Tube
Tape and
reel
May 2012
This is information on a product in full production.
Doc ID 022698 Rev 1
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