TI TPS60250

TPS60250
www.ti.com
SLVS769 – APRIL 2007
HIGH EFFICIENCY CHARGE PUMP FOR 7 WLEDs WITH I2C INTERFACE
FEATURES
•
•
•
•
•
•
•
•
•
•
DESCRIPTION
3.0-V to 6.0-V Input Voltage Range
×1 and ×1.5 Charge Pump
Fully Programmable Current with I2C
– 64 Dimming Steps with 25mA Maximum
(Sub and Main Display Banks)
– 4 Dimming Steps with 80mA Maximum
(DM5 for Auxiliary Application)
2% Current Matching for Sub LEDs at Light
Load Condition (Each 100µA)
750-kHz Charge Pump Frequency
Continuous 230-mA Maximum Output Current
Auto Switching Between ×1 and ×1.5 Mode for
Maximum Efficiency
Built-in Soft Start and Current Limit
Open Lamp Detection
16-Pin 3mm x 3mm QFN
APPLICATIONS
•
•
•
The TPS60250 is a high efficiency, constant
frequency charge pump DC/DC converter that uses a
dual mode 1× and 1.5× conversion to maximize
efficiency over the input voltage range. It drives up to
five white LEDs for a main display and up to two
white LEDs for a sub display with regulated constant
current for uniform intensity. By utilizing adaptive
1×/1.5× charge pump modes and very low-dropout
current regulators, the TPS60250 achieves high
efficiency over the full 1-cell lithium-battery input
voltage range.
Four enable inputs, ENmain, ENsub1, ENsub2, and
ENaux, available through I2C, are used for simple
on/off controls for the independent main, sub1, sub2,
and DM5 displays, respectively. To lower operating
current when using one sub display LED, the device
provides completely separate operation in sub
display LEDs.
The TPS60250 is available in a 16-pin 3mmx3mm
thin QFN.
Cellular Phones
PDA, PMP, GPS (Up To 4 Inch LCD Display)
Multidisplay Handheld Devices
Main Display
95
4 Main LED - 15 mA,
VF = 3.1 V
90
GND DM4 DM3 DM2
C1DM1
C2+
C2
1mF
C3
1mF
Efficiency - %
85
Sub Display
DS2
C2-
DS1
C1+
DM5
VIN SCLK SDAT
80
75
70
65
60
55
VOUT
50
C4
4.7mF
C1
1mF
3
I2C Interface
On/Off, Digital Dimming
Figure 1. Typical Application for Sub and Main
3.5
4
4.5
5
VI - Input Voltage - V
5.5
6
Figure 2. Efficiency vs Input Voltage
ORDERING INFORMATION (1)
(1)
PART NUMBER
PACKAGE
TA
TPS60250RTE
16 Pin 3 mm × 3 mm QFN (RTE)
–40°C to +85°C
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.
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.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2007, Texas Instruments Incorporated
TPS60250
www.ti.com
SLVS769 – APRIL 2007
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range (unless otherwise noted) (1)
VI
VALUE
UNIT
–0.3 to 7
V
650
mA
2
kV
CDM ESD Rating (3)
500
V
MM ESD Rating (4)
200
V
–40 to 85
°C
150
°C
–55 to 150
°C
Input voltage range (all pins)
MAX Output current limit
HBM ESD Rating
(2)
TA
Operating temperature range
TJ
Maximum operating junction temperature
TST
Storage temperature
(1)
(2)
(3)
(4)
Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings
only and functional operation of the device at these or any other conditions beyond those indicated under recommended operating
conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
The Human body model (HBM) is a 100-pF capacitor discharged through a 1.5-kΩ resistor into each pin. The testing is done according
JEDECs EIA/JESD22-A114.
Charged Device Model
Machine Model (MM) is a 200-pF capacitor discharged through a 500-nH inductor with no series resistor into each pin. The testing is
done according JEDECs EIA/JESD22-A115.
DISSIPATION RATINGS
PACKAGE
THERMAL
RESISTANCE, RθJC
THERMAL
RESISTANCE, RθJA
TA ≤ 25°C POWER
RATING
DERATING FACTOR
ABOVE TA = 25°C
TA = 85°C POWER
RATING
QFN 3×3 RTE
74.6°C/W
48.7°C/W
2.05 W
1.13 W
0.821 W
RECOMMENDED OPERATING CONDITIONS
MIN
NOM
3.0
MAX
6.0
UNIT
VI
Input voltage range
V
IO(max)
Maximum output current
230
mA
CI
Input capacitor
1.0
µF
CO
Output capacitor
4.7
µF
C1, C2
Flying capacitor
TA
Operating ambient temperature
–40
85
°C
TJ
Operating junction temperature
–40
125
°C
µF
1.0
ELECTRICAL CHARACTERISTICS
VI = 3.5 V, TA = –40°C to 85°C, typical values are at TA = 25°C (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
SUPPLY VOLTAGE
VI
3.0
750-kHz Switching in 1.5× Mode
(IMAIN_LED = 15 mA × 4, IO = 60 mA)
6.0
V
6.7
mA
IQ
Operating quiescent current
No switching in ×1 mode (IO = 100 µA)
68
µA
ISD
Shutdown current
Enable Control Register has 0x00
1.3
µA
VUVLO1
UVLO Threshold voltage1 (1)
VI falling
2.2
2.4
2.6
V
VUVLO2
UVLO Threshold voltage2 (2)
VI falling
1.2
1.3
1.5
V
(1)
(2)
2
Input voltage range
Shut down charge pump and power stage and keep I2C content
Shut down completely and come up with all 0's after device restart
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ELECTRICAL CHARACTERISTICS (continued)
VI = 3.5 V, TA = –40°C to 85°C, typical values are at TA = 25°C (unless otherwise noted)
PARAMETER
Vhys
TS
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Under-voltage lockout hysterisis
UVLO1
210
mV
Soft start time (3)
VI = 3 V, CO = 1 µF,
IMAIN_LED = 15 mA × 4
0.5
ms
CHARGE PUMP
Vout
Overvoltage limit
6.5
V
Fs
Switching frequency
750
kHz
RO
Open loop output impedance
×1 Mode, (VI– VO)/IO
1.2
× 1.5 Mode, (VI× 1.5 – VO)/IO VI = 3.0V (IO =
120mA)
3.5
5.0
0
±2%
±1%
±5%
Ω
CURRENT SINK
ISUB_LED = 100 µA × 2, VDXX = 0.4 V
Km_sub
Current matching of sub LEDs at light
load condition (4)
Km_main
LED to LED Current matching (5)
IMAIN_LED = 15 mA × 4,
3.0 V ≤ VI ≤ 4.2 V
Ka
Current accuracy
ILED = 15 mA
ID_MS
Maximum LED current of DM1-4 and
DS1-2
Main and Sub Display Current Register =
0×01&2(111111),
VDXX = 0.2 V
ID_DM5
Maximum LED current of DM5
Aux Display Current Register = 0×03
(XXXX11), VDM5 = 0.4 V
±7%
(6)
VDropOut
LED Drop out voltage
See
VTH_GU
1× Mode to 1.5× mode transition
threshold voltage (7)
VDXX Falling, 15 mA × 4 measured on the
lowest VDXX
VTH_GD
Input voltage hysteresis for 1.5× to 1×
mode transition
Measured as VI– (VO– VDXX_MIN), IMAIN_LED = 15
mA × 4
85
25.5
mA
80
mA
80
120
mV
100
120
mV
470
mV
SERIAL INTERFACE TIMING REQUIREMENTS
fmax
Clock frequency
twH(HIGH)
Pulse duration, clock high time
600
400
kHz
twL(LOW)
Pulse duration, clock low time
1300
tr
DATA and CLK rise time
300
ns
tf
DATA and CLK fall time
300
ns
th(STA)
High time (repeated) START
condition(after this period the first clock
pulse is generated)
600
ns
tsu(STA)
Setup time for repeated START
condition
600
ns
th(DATA)
Data input hold time
0
ns
tsu(DATA)
Data input setup time
100
ns
tsu(STO)
STOP condition setup time
600
ns
t(BUF)
Bus free time
1300
ns
ns
ns
I2C COMPATIBLE INTERFACE VOLTAGE SPECIFICATION (SCLK, SDAT, VIO)
VIL
Low-leveI input voltage
3.0V ≤ VI ≤ 6.0V
0
VIH
High-level input voltage
3.0V ≤ VI ≤ 6.0V
1.1
VOL
Low-level output voltage
ILOAD = 2 mA
(3)
(4)
(5)
(6)
(7)
0.5
V
V
0.4
V
Measurement Condition: From enabling the LED driver to 90% output voltage after VI is already up.
LED current matching is defined as: (ISUB_LED_WORST – IAVG_SUB) / IAVG_SUB
LED to LED Current Matching is defined as: (IMAIN_LED_WORST – IAVG_MAIN) / IAVG_MAIN
Dropout Voltage is defined as VDXX (WLED Cathode) to GND voltage at which current into the LED drops 10% from the LED current at
VDXX = 0.2 V, WLED current = 15 mA × 4.
As VI drops, VDXX eventually falls below the switchover threshold of 100mV, and TPS60250 switches to 1.5× mode. See the Operating
Principle section for details about the mode transition thresholds.
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PIN ASSIGNMENTS
QFN 16-PIN RTE
3mmX3mm
(TOP VIEW)
GND DM4 DM3 DM2
C1-
12
11
10
9
13
8
DM1
C2+ 14
7
DS2
C2-
6
DS1
5
DM5
15
C1+ 16
1
2
3
4
VOUT VIN SCLK SDAT
TERMINAL FUNCTIONS
TERMINAL
4
I/O
DESCRIPTION
1
O
Connect the anodes of the sub, main, and aux display white LEDs to this pin. Bypass decouple VOUT to
GND with a 4.7-µF or greater ceramic capacitor.
VIN
2
I
Supply voltage input. Connect to a 3-V to 6-V input supply source. Bypass VIN to GND with a 1-µF or
greater ceramic capacitor.
SCLK
3
I
I2C Interface
SDAT
4
I/O
I2C Interface
DM5
5
I
DS1
6
I
DS2
7
I
DM1
8
I
DM2
9
I
DM3
10
I
DM4
11
I
GND
12
–
Ground
C1–
13
–
Connect to the flying capacitor C1
C2+
14
–
Connect to the flying capacitor C2
C2–
15
–
Connect to the flying capacitor C2
C1+
16
–
Connect to the flying capacitor C1
NAME
NO.
VOUT
Current sink input. Connect the cathode of the aux display or the 5th main display white LED to this pin.
Current sink input. Connect the cathode of one of the sub display white LEDs to this pin.
Current sink input. Connect the cathode of one of the main display white LED to this pin.
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FUNCTIONAL BLOCK DIAGRAM
C 1+
16
VIN
2
C2-
C2+ C1-
15
14
VOUT
DM 4
DM 3
DM 2
DM 1
1
11
10
9
8
13
1X, 1.5X CHARGE PUMP
GEAR
CONTROL
&
OPEN LAMP
DETECTION
ENold
I2C
INTERFACE
7
DS2
6
DS1
5
DM5
12
GND
ENmain
Main Dimming
6
ENsub 1
ENsub 2
Sub Dimming
SCLK
3
ENaux
AUX Dimming
SDAT
6
6
4
BIAS, TEST, & MONITORING
TYPICAL CHARACTERISTICS
TABLE OF GRAPHS
DESCRIPTION
REF
Efficiency vs Input Voltage, 4 Main LED - 15mA, 25mA
Figure 3
Efficiency vs Input Voltage, 2 Sub LED with Light Load Condition, ×1 Mode Operation
Figure 4
Switch Resistance vs Free-Air Temperature, ×1 Mode, ILED = 230 mA
Figure 5
Switch Resistance vs Free-Air Temperature, ×1 Mode, ILED = 100 mA
Figure 6
Switch Resistance vs Free-Air Temperature, ×1.5 Mode Charge Pump Open-Loop , ILED = 230 mA
Figure 7
Switch Resistance vs Free-Air Temperature, ×1.5 Mode Charge Pump Open-Loop, ILED = 100 mA
Figure 8
Shutdown Current
Shutdown Current vs Input Voltage
Figure 9
Input Current
Input Current vs Supply Voltage, 4 Main LED
Figure 10
Efficiency
Output Impedance of ×1
and ×1.5 Mode
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TYPICAL CHARACTERISTICS (continued)
DESCRIPTION
REF
DM5 with Maximum 80
mA
DM5 Current vs Input Voltage, Programmed with 80 mA
Figure 11
Current Accuracy
WLED Current vs Input Voltage, 4 Main LED with 15 mA
Figure 12
EFFICIENCY
vs
INPUT VOLTAGE
(2 Sub LED with Light Load Condition,
× 1 Mode Operation)
EFFICIENCY
vs
INPUT VOLTAGE
(4 Main LED - 15mA, 25mA)
100
90
0.5 mA, VF = 2.7 V
Efficiency - %
Efficiency - %
1 mA, VF = 2.8 V
80
25 mA, VF = 3.79 V
80
70
60
0.2 mA, VF = 2.6 V
40
60
15 mA, VF = 3.43 V
20
50
3
4
5
3
6
4
5
VI - Input Voltage - V
VI - Input Voltage - V
Figure 3.
Figure 4.
SWITCH RESISTANCE
vs
FREE-AIR TEMPERATURE
(×1 Mode)
SWITCH RESISTANCE
vs
FREE-AIR TEMPERATURE
(×1 Mode)
6
1.15
1.10
1.10
ILED = 230 mA
ILED = 100 mA
VI = 3.3 V
1.05
VI = 3.3 V
Switch Resistance - W
Switch Resistance - W
1.05
1
VI = 3.6 V
0.95
0.90
VI = 3.9 V
0.85
1
VI = 3.6 V
0.95
0.90
0.85
0.80
VI = 3.9 V
0.80
0.75
0.75
0.70
0.70
-40
-20
0
20
40
60
80
0.65
-40
TA - Free-Air Temperature - °C
Figure 5.
6
-20
0
20
40
TA - Free-Air Temperature - °C
Figure 6.
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80
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SWITCH RESISTANCE
vs
FREE-AIR TEMPERATURE
(×1.5 Mode Charge Pump Open-Loop)
SWITCH RESISTANCE
vs
FREE-AIR TEMPERATURE
(×1.5 Mode Charge Pump Open-Loop)
3.8
3.8
ILED = 230 mA
ILED = 100 mA
3.6
Switch Resistance - W
Switch Resistance - W
3.6
VI = 3 V
3.4
3.2
3
3.4
VI = 3 V
3.2
3
2.8
2.8
-40
-20
40
20
TA - Free-Air Temperature - °C
0
60
2.6
-40
80
0
20
40
Figure 7.
Figure 8.
SHUTDOWN CURRENT
vs
INPUT VOLTAGE
INPUT CURRENT
vs
SUPPLY VOLTAGE
(4 Main LED)
ICC - Input Current - A
8
6
4
TA = 85°C
0.16
0.15
0.14
0.13
0.12
80
25 mA
0.11
0.10
0.09
0.08
0.07
0.06
15 mA
0.05
0.04
0.03
0.02
TA = 25°C
TA = -40°C
60
TA - Free-Air Temperature - °C
10
Shutdown Current - mA
-20
2
2 mA
0.01
0
3
5
4
6
3
VI - Input Voltage - V
Figure 9.
5
4
6
VI - Input Voltage - V
Figure 10.
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DM5 CURRENT
vs
INPUT VOLTAGE
(Programmed with 80 mA)
WLED CURRENT
vs
INPUT VOLTAGE
(4 Main LED with 15 mA)
0.08
0.016
IDM2
IDM3
0.07
0.06
0.35 V
0.05
IDM1
0.3 V
WLED Current - A
DM5 Current - A
0.4 V
0.25 V
0.2 V
0.15 V 0.1 V
0.04
0.03
0.05 V
IDM4
0.014
0.012
0.02
0.01
0
2.5
0.010
3
3.5
4
3
VI - Input Voltage - V
5
VI - Input Voltage - V
Figure 11.
8
4
Figure 12.
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APPLICATION INFORMATION
APPLICATION OVERVIEW
Most of the current handsets fall into one of three categories. First is the clamshell design, with a main display
on the inside, a secondary display on the outside and a keypad backlight. Second is the bar design, with a main
display and a keypad backlight. Third is the slide type (slide-up and slide-down) design, with a main display and
two keypad banks (inside and outside). The TPS60250 is well suited for use in these three major phone designs
because it has 7 individually regulated white LED current paths and that drive up to five white LEDs in main
display and up to two white LEDs in sub display with regulated constant current for uniform intensity. The main
and sub display LED channels drive up to 25mA and an auxiliary LED output (DM5) drives up to 80mA that can
be assigned for keypad backlight, torch light or low cost/weak camera flash application using I2C interface.
The TPS60250 circuit uses only 4 external components: the input/output capacitors and 2 chargepump flying
capacitors. The few external components combined with the small 3mm×3mm QFN package provide for a small
total solution size. By combining independent control of three separate banks of backlight LEDs with low cost
and weak flash capability, the TPS60250 helps designers minimize power consumption especially in case of
light load condition while reducing component count and package size.
OPERATING PRINCIPLE
Charge pumps are becoming increasingly attractive in battery-operated applications where board space and
maximum height of the converter are critical constraints. The major advantage of a charge pump is the use of
only capacitors as storage elements. The TPS60250 chargepump provides regulated LED current from a 3-V to
6-V input source. It operates in two modes. The 1× mode, where the input is connected to the output through a
pass element, and a high efficiency 1.5× charge pump mode. The IC maximizes power efficiency by operating in
1× and 1.5× modes as input voltage and LED current conditions require. The mode of operation is automatically
selected by comparing the forward voltage of the WLED plus the voltage of current sink for each LED with the
input voltage. The IC starts up in 1× mode, and automatically transitions to 1.5× if the voltage at any current sink
input (DM_or DS_) falls below the 100-mV transition voltage. The IC returns to 1× mode as the input rises.
Figure 13 provides a visual explanation of the 1× to 1.5× transition.
In 1.5× mode, the internal oscillator determines the charge/discharge cycles for the flying capacitors. During a
charge cycle, the flying capacitors are connected in series and charged up to the input voltage. After the on-time
of the internal oscillator expires, the flying capacitors are reconfigured to be in parallel and then connected in
series to the input voltage. This provides an output of 1.5× the input voltage. After the off-time of the internal
oscillator expires, another charge cycle initiates and the process repeats.
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APPLICATION INFORMATION (continued)
VA
VO
VI
VF
CP WLED Driver
VDX
VI
x1 Operating
Area
x1.5 Operating
Area
VHYS
VB
VC
Figure 13. Input Voltage Hysteresis Between ×1 and ×1.5 Mode
As shown in Figure 13, there is input voltage hysteresis voltage between 1× and 1.5× mode to ensure stable
operation during mode transition. For the 1 cell Li-Ion battery input voltage range, the TPS60250 operates in 1×
mode when a fully charged battery is installed. Once the battery voltage drops below the VB level, which is the
mode transition voltage from 1× to 1.5×, the WLED driver operates in 1.5× mode. Once in 1.5× mode, the battery
voltage must rise to the VC level in order to transition from 1.5× to 1×. This hysteresis ensures stable operation
when there is some input voltage fluctuation at the 1×/1.5× mode transition. The WLED driver provides a typical
280mV hysteresis voltage (VHYS) that changes based on LED current, to prevent oscillating between modes.
The transition voltage, VB, depends on VDX (the mode transition threshold voltage), VF (WLED forward voltage
drop) and VA (the drop out voltage of the charge pump stage) and is calculated as follows:
VB = VA + VF + VDX
VA = ROUT1X× ILEDTOTAL
Where ROUT1X is the 1× mode output impedance of the IC. See the Electrical Characteristics table for output
impedance specifications.
The TPS60250 switches up to 1.5× mode when the input voltage is below VB and remains in 1.5× mode as long
as the input is lower than VC. 1.5× Mode is exited when the input voltage rises above VC. VC is calculated as:
VC = VF + 470 mV
The input voltage mode transition hysteresis voltage (VHYS) between 1× and 1.5× is calculated using the
following equation.
VHYS = VC– VB = 520 mV – VDX– VA, where VDX = 100mV
Note that VA is the key factor in determining VHYS and is dependant on the 1× mode charge pump output
impedance and WLED current.
10
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APPLICATION INFORMATION (continued)
LED CURRENT SINKS (DM_, DS_)
The TPS60250 has constant current sinks which drive seven individual LED current paths. Each current sink
regulates the LED current to a constant value determined by the I2C interface. The internal register addressing
allows the LED main channels DM1~DM5 to be controlled independently from the LED sub channels DS1~DS2.
All the LED channels sink up to 25mA of current except DM5 which has an 80-mA maximum current when
configured as an auxiliary output. Using the I2C interface, the user may assign DM5 to the main display bank
with up to 25-mA current or as an auxiliary output for torch or keypad light or low/weak camera flash with 80-mA
current. DM5 has 64 dimming steps same as main and sub display banks when assigned to the main display.
However, it has its own current programming register and enable control. When assigned as an auxiliary, DM5
has 4 dimming steps (full scale, 70%, 40%, 20%).
These optimized current sinks minimize the voltage headroom required to drive each LED and maximize power
efficiency by increasing the amount of time the controller stays in 1× mode before transitioning to 1.5× mode.
OPEN LAMP DETECTION
In system production it is often necessary to leave LED current paths open depending on the phone model. For
example, one phone may use 2 LEDs to backlight the main display while another uses 4 LEDs. Rather than use
two different ICs for these different phone applications, the TPS60250 may be used in both applications with no
additional efficiency loss in the 2 LED applications. In traditional LED driver applications when an LED current
path is open, the current sink voltage falls to ground and the current regulation circuitry drives the output to a
maximum voltage in an attempt to regulate the current for the missing LED path. This severely reduces the
system efficiency. The TPS60250 uses 7 internal comparators to detect when one or more open LED condition
occurs and shut down prevent it from forcing the device to gear up the open current sink. The open lamp
detection is enabled/disabled using the I2C interface.
CAPACITOR SELECTION
The TPS60250 is optimized to work with ceramic capacitors with a dielectric of X5R or better. The two flying
capacitors must be the same value for proper operation. The 750-kHz switching frequency requires that the
flying capacitor be less than 4.7µF. Use of 1-µF ceramic capacitors for both chargepump flying capacitors is
recommended.
For good input voltage filtering, low ESR ceramic capacitors are recommended. A 1-µF ceramic input capacitor
is sufficient for most of the applications. For better input voltage filtering this value can be increased.
The output capacitor controls the amount of ripple on the output. Since small ripple is undetectable by the
human eye, a 4.7-µF output capacitor works well. If better output filtering and lower ripple is desired, a larger
output capacitor may be used.
SETTING THE LED CURRENT
Figure 14. Dimming Steps for Sub, Main, and Keypad Backlight
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APPLICATION INFORMATION (continued)
Figure 14 shows the dimming steps for sub, main, and auxiliary display banks in the 25mA maximum current
application. In order to satisfy today's requirement on LED current, the TPS60250 covers low LED current area
from 100µA to 1.5mA with 100-µA dimming step (total 16 steps for 25-mA maximum current) for the new LCD
panels which have improved transparency rates. For LED currents in the range from 2mA to 25mA, the device
uses 48 dimming steps with 0.5mA step. Also, DM5 has 4 dimming steps once the current path is assigned for
auxiliary applications with maximum 80-mA current.
SERIAL INTERFACE
The serial interface is compatible with the standard and fast mode I2C specifications, allowing transfers at up to
400 kHz. The interface adds flexibility to the WLED driver solution, enabling most functions to be programmed to
new values depending on the instantaneous application requirements. Register contents remain intact as long
as VCC remains above UVLO2 (typical 1.3V).
For normal data transfer, DATA is allowed to change only when CLK is low. Changes when CLK is high are
reserved for indicating the start and stop conditions. During data transfer, the data line must remain stable
whenever the clock line is high. There is one clock pulse per bit of data. Each data transfer is initiated with a
start condition and terminated with a stop condition. When addressed, the TPS60250 device generates an
acknowledge bit after the reception of each byte. The master device (microprocessor) must generate an extra
clock pulse that is associated with the acknowledge bit. The TPS60250 device must pull down the DATA line
during the acknowledge clock pulse so that the DATA line is a stable low during the high period of the
acknowledge clock pulse. Setup and hold times must be taken into account. During read operations, a master
must signal the end of data to the slave by not generating an acknowledge bit on the last byte that was clocked
out of the slave. In this case, the slave TPS60250 device must leave the data line high to enable the master to
generate the stop condition.
DATA
CLK
Data line
stable;
data valid
Change
of data
allowed
Figure 15. Bit Transfer on the Serial Interface
CE
DATA
CLK
S
P
START Condition
STOP Condition
Figure 16. START and STOP Conditions
12
Submit Documentation Feedback
TPS60250
www.ti.com
SLVS769 – APRIL 2007
APPLICATION INFORMATION (continued)
SCLK
...
SDAT
A5
A6
Start
A4
...
... A0
R/W
AC
K
0
0
R7
R6
R5
...
... R0
AC
K
D7
D6 D5
...D0
0
Slave Address
AC
K
0
Register Address
Data
Stop
NOTE: SLAVE=TPS60250
Figure 17. Serial I/F READ From TPS60250: Protocol A
SCLK
SDAT
...
A6
.. A0
...
R/W
AC
K
0
0
R7
.. R0
...
AC
K
A6
.. A0
0
...
R/W
AC
K
1
0
Start
Slave Address
NOTE: SLAVE=TPS60250
Register
Address
Slave Address
D7
.. D0
Slave
Drives
the Data
Repeated
Start
AC
K
Master
Drives
ACK and Stop
Stop
Figure 18. Serial I/F READ From TPS60250: Protocol B
Figure 19. Serial I/F Timing Diagram
The I2C interface uses a combined protocol in which the START condition and the Slave Address are both
repeated. The TPS60250 provides 2 I2C Slave Address using internal EEPROM in case more than 1 device is
used in the system. The primary I2C Slave Address is 1110111. For alternative I2C address, contact the factory.
Submit Documentation Feedback
13
TPS60250
www.ti.com
SLVS769 – APRIL 2007
APPLICATION INFORMATION (continued)
Enable Control Register (Address: 0x00h)
ENABLE
B7
B6
B5
B4
B3
B2
B1
B0
X
ENold
ENmain
ENsub2
ENsub1
ENaux
DM5H
DM5L
BIT NAME
Bit 6
ENold (Enable Open Lamp Detection)
1: Open Lamp Detection Enabled
0: Open Lamp Detection Disabled
Bit 5
ENmain
1: Enable Main Display LEDs (DM1-DM4)
0: Disable Main Display LEDs
Bit 4
ENsub2
1: Enable Sub Display LED 2 (DS2)
0: Disable Sub Display LED 2
Bit 3
ENsub1
1: Enable Sub Display LED 1 (DS1)
0: Disable Sub Display LED 1
Bit 2
ENaux
1: Enable Aux Display LED (DM5)
0: Disable Aux Display LED
Bits 1,0
DM5H, DM5L
DM5H
(B1)
DM5L
(B0)
0
0
Shutdown mode. All outputs disabled, all internal registers set to 0x00h
0
1
Enable the IC and Group DM5 as main display with maximum current of 25mA
1
0
Enable the IC and set DM5 as Aux output with maximum current of 80mA.
Dimming steps determined by Iaux0 and Iaux1 bits.
1
1
Shutdown mode. All outputs disabled, all internal registers set to 0x00h
DM5 Mode and Shutdown Mode
Sub Display Current Control Register (Address: 0x01h)
SUB DISP
CURRENT
B7
B6
B5
B4
B3
B2
B1
B0
BIT NAME
X
X
Isub5
Isub4
Isub3
Isub2
Isub1
Isub0
Bits 5 - 0
Isub5 - Isub0 (total 64 steps)
6-Bit command (64 steps) to these bits sets the current for DS1 and DS2.
For LED currents between 0 and 1.5mA, one step = 0.1mA increment
For LED currents between 1.5 and 25.5mA, one step = 0.5mA increment
Main Display Current Control Register (Address: 0x02h)
MAIN DISP
CURRENT
B7
B6
B5
B4
B3
B2
B1
B0
BIT NAME
X
X
Imain5
Imain4
Imain3
Imain2
Imain1
Imain0
Bits 5 - 0
14
Imain5 - Imain0 (total 64 steps)
6-Bit command (64 steps) to these bits sets the current for DM1-DM4.
For LED currents between 0 and 1.5mA, one step = 0.1mA increment
For LED currents between 1.5 and 25.5mA, one step = 0.5mA increment
Submit Documentation Feedback
TPS60250
www.ti.com
SLVS769 – APRIL 2007
Aux Output Brightness and Operation Mode Control Register (Address: 0x03h)
AUX DISP
CURRENT
B7
B6
B5
B4
B3
B2
B1
B0
BIT NAME
Iaux5
Iaux4
Iaux3
Iaux2
Iaux1
Iaux0
Mode1
Mode0
Bits 7 - 2 (DM5 set to Main Display Mode)
Iaux5 - Iaux0 (total 64 steps)
6-Bit command (64 steps) to these bits sets the current for DM5.
For LED currents between 0 and 1.5mA, one step = 0.1mA increment
For LED currents between 1.5 and 25.5mA, one step = 0.5mA increment
Bits 7 - 2 (DM5 set to Aux Display Mode)
Bits 1,0
Iaux5
(B7)
Iaux4
(B6)
Iaux3
(B5)
Iaux2
(B4)
Iaux1
(B3)
Iaux0
(B2)
Aux Dimming
Step
X
X
X
X
0
0
20%
X
X
X
X
0
1
40%
X
X
X
X
1
0
70%
X
X
X
X
1
1
100%
Mode1, Mode0
Mode1 Mode0
(B1)
(B0)
TPS60250 Mode
0
0
Auto-Switchover Mode. The TPS60250 selects
1×/1.5× mode as described in the Operating Principle
section.
0
1
1× Mode. TPS60250 remains in 1× mode regardless
of the input voltage. LED current may not regulate at
lower input voltages when in this mode.
1
0
1.5× Mode. TPS60250 remains in 1.5× mode
regardless of the input voltage.
1
1
Auto-Switchover Mode. The TPS60250 selects
1×/1.5× mode as described in the Operating Principle
section.
Submit Documentation Feedback
15
TPS60250
www.ti.com
SLVS769 – APRIL 2007
APPLICATION CIRCUITS
Main Display
GND DM4 DM3 DM2
C1DM1
C2
1 mF
C3
1mF
C2+
DS2
C2-
DS1
C1+
DM5
VIN SCLK SDAT
Sub Display
VOUT
C4
4.7mF
C1
1mF
I2C Interface
On/Off, Digital Dimming
Figure 20. The Typical Application Circuit for Sub and Main Display
As shown in Figure 20, this is a typical application circuit for a clam shell phone with 5 main LEDs and 2 sub
LEDs. Recently, the LCD panel makers have developed a new panel that has improved the transparency rate
which makes the system efficiency with a 100-µA LED current a critical load point. To meet system efficiency
requirements with the light load conditions for the new LCD operating panel, the TPS60250 has a maximum
55-µA operating current with the 100-µA output load condition. In this application, the controller always operates
in 1× mode due to the WLED's low forward voltage drop (about 2.6VF with a 100-µA WLED current). Thus, the
total efficiency at a light load condition is determined using Equation 1:
IO VF
h Light +
Vin ǒI O ) I opǓ
(1)
Where:
IO: Output Load (WLED) Current
VF: Forward Voltage Drop of WLED
Vin: Input Voltage
Iop: Operating Current of LED Driver
16
Submit Documentation Feedback
TPS60250
www.ti.com
SLVS769 – APRIL 2007
Main Display
Auxiliary Port for Key Pad
or Flash Light
GND DM 4 DM3 DM2
C1DM1
C2
1mF
C3
1mF
C2+
DS 2
C2-
DS 1
C1+
DM5
VIN SCLK SDAT
Sub Display
VOUT
C4
4.7 mF
2
C1
1uF
I C Interface
On/Off, Digital Dimming
Figure 21. The Typical Application Circuit for Sub, Main, and Keypad Backlight
Figure 21 shows the typical application circuit for sub, main, and keypad backlight. In this application, DM5 is
assigned as the auxiliary input for the keypad lighting application.
LAYOUT GUIDELINES
There are several points to consider when laying out a PCB for charge pump based solutions. In general, all
capacitors should be as close as possible to the device. This is especially important when placing the flying
capacitors (C2, C3 in Figure 20 and Figure 21). In cases where DM5 is assigned for torch/flash applications,
with a maximum 80-mA WLED current, this current path must be kept wide to reduce the trace resistance.
Submit Documentation Feedback
17
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements,
improvements, and other changes to its products and services at any time and to discontinue any product or service without notice.
Customers should obtain the latest relevant information before placing orders and should verify that such information is current and
complete. All products are sold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment.
TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TI’s
standard warranty. Testing and other quality control techniques are used to the extent TI deems necessary to support this
warranty. Except where mandated by government requirements, testing of all parameters of each product is not necessarily
performed.
TI assumes no liability for applications assistance or customer product design. Customers are responsible for their products and
applications using TI components. To minimize the risks associated with customer products and applications, customers should
provide adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right, copyright, mask
work right, or other TI intellectual property right relating to any combination, machine, or process in which TI products or services
are used. Information published by TI regarding third-party products or services does not constitute a license from TI to use such
products or services or a warranty or endorsement thereof. Use of such information may require a license from a third party under
the patents or other intellectual property of the third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of information in TI data books or data sheets is permissible only if reproduction is without alteration and is
accompanied by all associated warranties, conditions, limitations, and notices. Reproduction of this information with alteration is an
unfair and deceptive business practice. TI is not responsible or liable for such altered documentation.
Resale of TI products or services with statements different from or beyond the parameters stated by TI for that product or service
voids all express and any implied warranties for the associated TI product or service and is an unfair and deceptive business
practice. TI is not responsible or liable for any such statements.
TI products are not authorized for use in safety-critical applications (such as life support) where a failure of the TI product would
reasonably be expected to cause severe personal injury or death, unless officers of the parties have executed an agreement
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requirements concerning their products and any use of TI products in such safety-critical applications, notwithstanding any
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TI products are neither designed nor intended for use in military/aerospace applications or environments unless the TI products are
specifically designated by TI as military-grade or "enhanced plastic." Only products designated by TI as military-grade meet military
specifications. Buyers acknowledge and agree that any such use of TI products which TI has not designated as military-grade is
solely at the Buyer's risk, and that they are solely responsible for compliance with all legal and regulatory requirements in
connection with such use.
TI products are neither designed nor intended for use in automotive applications or environments unless the specific TI products
are designated by TI as compliant with ISO/TS 16949 requirements. Buyers acknowledge and agree that, if they use any
non-designated products in automotive applications, TI will not be responsible for any failure to meet such requirements.
Following are URLs where you can obtain information on other Texas Instruments products and application solutions:
Products
Applications
Amplifiers
amplifier.ti.com
Audio
www.ti.com/audio
Data Converters
dataconverter.ti.com
Automotive
www.ti.com/automotive
DSP
dsp.ti.com
Broadband
www.ti.com/broadband
Interface
interface.ti.com
Digital Control
www.ti.com/digitalcontrol
Logic
logic.ti.com
Military
www.ti.com/military
Power Mgmt
power.ti.com
Optical Networking
www.ti.com/opticalnetwork
Microcontrollers
microcontroller.ti.com
Security
www.ti.com/security
Low Power
Wireless
www.ti.com/lpw
Telephony
www.ti.com/telephony
Video & Imaging
www.ti.com/video
Wireless
www.ti.com/wireless
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2007, Texas Instruments Incorporated
PACKAGE OPTION ADDENDUM
www.ti.com
7-May-2007
PACKAGING INFORMATION
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
TPS60250RTER
ACTIVE
QFN
RTE
16
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
TPS60250RTET
ACTIVE
QFN
RTE
16
250
CU NIPDAU
Level-2-260C-1 YEAR
Green (RoHS &
no Sb/Br)
Lead/Ball Finish
MSL Peak Temp (3)
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in
a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check
http://www.ti.com/productcontent for the latest availability information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and
package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS
compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder
temperature.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is
provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the
accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take
reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on
incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited
information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI
to Customer on an annual basis.
Addendum-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
17-May-2007
TAPE AND REEL INFORMATION
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
Device
17-May-2007
Package Pins
Site
Reel
Diameter
(mm)
Reel
Width
(mm)
A0 (mm)
B0 (mm)
K0 (mm)
P1
(mm)
W
Pin1
(mm) Quadrant
TPS60250RTER
RTE
16
MLA
330
12
3.3
3.3
1.1
8
12
PKGORN
T2TR-MS
P
TPS60250RTET
RTE
16
MLA
177
12
3.3
3.3
1.1
8
12
PKGORN
T2TR-MS
P
TAPE AND REEL BOX INFORMATION
Device
Package
Pins
Site
Length (mm)
Width (mm)
Height (mm)
TPS60250RTER
RTE
16
MLA
342.9
336.6
28.58
TPS60250RTET
RTE
16
MLA
190.0
212.7
31.75
Pack Materials-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
17-May-2007
Pack Materials-Page 3
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements,
improvements, and other changes to its products and services at any time and to discontinue any product or service without notice.
Customers should obtain the latest relevant information before placing orders and should verify that such information is current and
complete. All products are sold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment.
TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TI’s
standard warranty. Testing and other quality control techniques are used to the extent TI deems necessary to support this
warranty. Except where mandated by government requirements, testing of all parameters of each product is not necessarily
performed.
TI assumes no liability for applications assistance or customer product design. Customers are responsible for their products and
applications using TI components. To minimize the risks associated with customer products and applications, customers should
provide adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right, copyright, mask
work right, or other TI intellectual property right relating to any combination, machine, or process in which TI products or services
are used. Information published by TI regarding third-party products or services does not constitute a license from TI to use such
products or services or a warranty or endorsement thereof. Use of such information may require a license from a third party under
the patents or other intellectual property of the third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of information in TI data books or data sheets is permissible only if reproduction is without alteration and is
accompanied by all associated warranties, conditions, limitations, and notices. Reproduction of this information with alteration is an
unfair and deceptive business practice. TI is not responsible or liable for such altered documentation.
Resale of TI products or services with statements different from or beyond the parameters stated by TI for that product or service
voids all express and any implied warranties for the associated TI product or service and is an unfair and deceptive business
practice. TI is not responsible or liable for any such statements.
TI products are not authorized for use in safety-critical applications (such as life support) where a failure of the TI product would
reasonably be expected to cause severe personal injury or death, unless officers of the parties have executed an agreement
specifically governing such use. Buyers represent that they have all necessary expertise in the safety and regulatory ramifications
of their applications, and acknowledge and agree that they are solely responsible for all legal, regulatory and safety-related
requirements concerning their products and any use of TI products in such safety-critical applications, notwithstanding any
applications-related information or support that may be provided by TI. Further, Buyers must fully indemnify TI and its
representatives against any damages arising out of the use of TI products in such safety-critical applications.
TI products are neither designed nor intended for use in military/aerospace applications or environments unless the TI products are
specifically designated by TI as military-grade or "enhanced plastic." Only products designated by TI as military-grade meet military
specifications. Buyers acknowledge and agree that any such use of TI products which TI has not designated as military-grade is
solely at the Buyer's risk, and that they are solely responsible for compliance with all legal and regulatory requirements in
connection with such use.
TI products are neither designed nor intended for use in automotive applications or environments unless the specific TI products
are designated by TI as compliant with ISO/TS 16949 requirements. Buyers acknowledge and agree that, if they use any
non-designated products in automotive applications, TI will not be responsible for any failure to meet such requirements.
Following are URLs where you can obtain information on other Texas Instruments products and application solutions:
Products
Applications
Amplifiers
amplifier.ti.com
Audio
www.ti.com/audio
Data Converters
dataconverter.ti.com
Automotive
www.ti.com/automotive
DSP
dsp.ti.com
Broadband
www.ti.com/broadband
Interface
interface.ti.com
Digital Control
www.ti.com/digitalcontrol
Logic
logic.ti.com
Military
www.ti.com/military
Power Mgmt
power.ti.com
Optical Networking
www.ti.com/opticalnetwork
Microcontrollers
microcontroller.ti.com
Security
www.ti.com/security
RFID
www.ti-rfid.com
Telephony
www.ti.com/telephony
Low Power
Wireless
www.ti.com/lpw
Video & Imaging
www.ti.com/video
Wireless
www.ti.com/wireless
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2007, Texas Instruments Incorporated