LM27965,LM27965_07,LM27965SQ,LM27965SQ-M,LM27965SQX,LM27965SQX-M

Part No.:
LM27965,LM27965_07,LM27965SQ,LM27965SQ-M,LM27965SQX,LM27965SQX-M
Download:
Download
Description:
Dual Display White LED Driver with I2C Compatible Brightness Control
File Size:
354 K
Page:
14 Pages
Logo:
Maker:
NSC [ NATIONAL SEMICONDUCTOR ]
PCB Prototype

July 19, 2018:

LM340S-12

LM341-12

LM3S2276

LMR70503

LMZ1601-7R

LMZ30604

LNK406EG

LP08

LPC1114FHN33/201

LQFP

LT3782EFE

LTC1041

PCB Datasheet:1PCB Datasheet:1
LM27965 Dual Display White LED Driver System with I
2
C Compatible Brightness Control
October 2007
LM27965
Dual Display White LED Driver with I2C Compatible
Brightness Control
General Description
The LM27965 is a highly integrated charge-pump-based du-
al-display LED driver. The device can drive up to 9 LEDs in
parallel with a total output current of 180mA. Regulated inter-
nal current sinks deliver excellent current and brightness
matching in all LEDs.
The LED driver current sinks are split into three independently
controlled groups. The primary group can beconfigurabled
with 4 or 5 LEDs, for backlighting a larger main display and
the second group can be configured with 2 or 3 LEDs, for
backlighing a smaller secondary display. An additional, inde-
pendently controlled led driver is provided for driving an indi-
cator or general purpose LED. The LM27965 has an I
2
C
compatible interface that allows the user to independently
control the brightness on each bank of LEDs.
The device provides excellent efficiency without the use of an
inductor by operating the charge pump in a gain of 3/2, or in
Pass-Mode. The proper gain for maintaining current regula-
tion is chosen based on LED forward voltage, so that effi-
ciency is maximized over the input voltage range.
The LM27965 is available in National's small 24-pin Leadless
Leadframe Package (LLP-24).
Features
91% Peak LED Drive Efficiency
No Inductor Required
0.3% Current Matching
Drives LEDs with up to 30mA per LED
180mA of total drive current
I
2
C Compatible Brightness Control Interface
Adaptive 1× - 3/2× Charge Pump
Resistor-Programmable Current Settings
External Chip RESET Pin
Extended Li-Ion Input: 2.7V to 5.5V
Small low profile industry standard leadless package, LLP
24 : (4mm x 4mm x 0.8mm)
25mm
2
total solution size
Two I
2
C Compatible Chip Address Options: 0x36 for
LM27965SQ and 0x38 for LM27965SQ-M
Applications
Mobile Phone Display Lighting
PDA Backlighting
General LED Lighting
Typical Application Circuit
20155001
© 2007 National Semiconductor Corporation
201550
www.national.com