1
FEATURES
DESCRIPTION
APPLICATIONS
95
90
85
80
75
70
65
60
55
50
Efficiency-%
3
3.5
4
4.5
5
5.5
6
V -InputVoltage-V
I
4MainLED-15mA,V =3.1V
F
C 1+
SDAT
DS 1 DS 2 DM5
VIO
NC
GND
NC-G
NC
DM1
DM 2
DM3
DM4
IS
ENA
GND
C 2+
C2-
C 1-
VOUT
VIN
MainDisplay
C 1
4.7uF
C4
4.7uF
C2
1uF
C3
1uF
SubDisplay
SCLK
I
2CInterface
1.8VforI /O
Input
Auxiliary PortforKey Pad
orFlash Light
SLVS767C – APRIL 2007 – REVISED NOVEMBER 2007
www.ti.com
HIGH EFFICIENCY CHARGE PUMP FOR 7 WLEDs WITH I2C INTERFACE
PDA, PMP, GPS (Up To 4 Inch Display)
Multidisplay Handheld Devices
3.0-V to 6.0-V Input Voltage Range
×1 and ×1.5 Charge Pump
Fully Programmable Current with I2C
The
TPS60251
is
a
high
efficiency,
constant
–
64 Dimming Steps with 25mA Maximum
frequency charge pump DC/DC converter that uses a
(Sub and Main Display Banks)
dual mode 1
× and 1.5× conversion to maximize
–
4 Dimming Steps with 80mA Maximum
efficiency over the input voltage range. It drives up to
(DM5 for Auxiliary Application)
five white LEDs for a main display and up to two
white LEDs for a sub display with regulated constant
2% Current Matching for Sub LEDs at Light
current for uniform intensity. By utilizing adaptive
Load Condition (Each 100
A)
1
×/1.5× charge pump modes and very low-dropout
750-kHz Charge Pump Frequency
current regulators, the TPS60251 achieves high
Continuous 230-mA Maximum Output Current
efficiency over the full 1-cell lithium-battery input
voltage range.
Auto Switching Between ×1 and ×1.5 Mode for
Maximum Efficiency
Four enable inputs, ENmain, ENsub1, ENsub2, and
ENaux, available through I2C, are used for simple
Built-in Soft Start and Current Limit
on/off controls for the main, sub1, sub2, and DM5
Hardware Enable/Disable
displays, respectively. To lower operating current
Open Lamp Detection
when using one sub display LED, the device provides
24-Pin 4mm x 4mm QFN
independent operation in sub display LEDs.
The TPS60251 is available in a 24-pin 4mmx4mm
thin QFN.
Cellular Phones
Figure 1. Typical Application for Sub and Main
Figure 2. Efficiency vs Input Voltage
ORDERING INFORMATION(1)
PART NUMBER
PACKAGE
TA
TPS60251RTW
24 Pin 4 mm
× 4 mm QFN (RTW)
–40
°C to +85°C
(1)
For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI
web site at www.ti.com.
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Copyright 2007, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.