MAXIM MAX1707 Technical data

General Description

The MAX1707 provides complete light management for
main display backlight, subdisplay backlight (or RGB
indicator), and white LED camera flash with regulated
constant current up to 610mA total. By utilizing adap­tive 1x/1.5x/2x charge-pump modes and very-low­dropout current regulators, it achieves high efficiency
over the full 1-cell Li+ battery input voltage range. The
1MHz fixed-frequency switching allows for tiny external
components while the regulation scheme is optimized
to ensure low EMI and low input ripple. An integrated
derating function protects the LEDs from overheating
during high ambient temperatures.

The MAX1707 features an internally trimmed reference
to set the maximum LED current. An I2C†serial port is
used for on/off control and setting the LED currents in
32 linear steps. When using the RGB indicator, the I2C
port provides 32k colors and programmable ramp­up/down rates. The camera flash may be turned on/off
by the I2C port or a separate digital logic input.

Applications

Cell Phones and Smartphones

PDAs, Digital Cameras, Camcorders

Displays with Up to 11 LEDs

Features

♦ Guaranteed 610mA Continuous Drive Capability

4 LEDs at 30mA Each for Main Display
3 LEDs at 30mA Each for Sub or RGB
400mA Total for Flash

♦ 2-Wire I2C Serial Port

5-Bit (32-Step) Linear Dimming
32k Colors
Ramp-Up/Down Rates

♦ 92% Peak/83% Avg Efficiency (P

LED/PBATT

)

♦ Adaptive 1x/1.5x/2x Mode Switchover

♦ 0.3% (typ) LED Current Accuracy and Matching

♦ Low Input Ripple and EMI

♦ Low 0.1µA Shutdown Current

♦ Output Overvoltage Protection

♦ Thermal Derating Function Protects LEDs

♦ 24-Pin 4mm x 4mm Thin QFN Package

MAX1707

Light-Management IC with Efficient 1x/1.5x/2x

Charge Pump for Backlight/Flash/RGB LEDs

________________________________________________________________ Maxim Integrated Products 1

Ordering Information

MAX1707

1µF1µF

10µF

0.1µF

IN
PIN

SDA

SCK

STB

GND

OUT

C1P C1N

PGND

C2P

FLASH

MAIN

C2N

4.7µF

I

2

C PORT

ON/OFF AND

BRIGHTNESS

INPUT

2.7V TO 5.5V

OUTPUT
UP TO 610mA

M1
M2

M3
M4

S1
S2
S3
F1
F2
F3
F4

STROBE

ON/OFF

V

LOGIC

V

DD

SUB OR RGB

Typical Operating Circuit

19-3744; Rev 0; 7/05

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

Pin Configuration appears at end of data sheet.

EVALUATION KIT

AVAILABLE

PART

PIN­PACKAGE

PKG

CODE

MAX1707ETG

24 Thin QFN
4mm x 4mm

T2444-4

†

Purchase of I2C components from Maxim Integrated Products,
Inc., or one of its sublicensed Associated Companies, conveys
a license under the Philips I

2

C Patent Rights to use these com-

ponents in an I

2

C system, provided that the system conforms to

the I

2

C Standard Specification as defined by Philips.

查询MAX1707供应商

TEMP RANGE

-40°C to +85°C

MAX1707

Light-Management IC with Efficient 1x/1.5x/2x
Charge Pump for Backlight/Flash/RGB LEDs

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VIN= V

PIN

= VDD= 3.6V, V

GND

= V

PGND

= 0V, temperature derating disabled, TA= -40°C to +85°C, typical values are at TA=

+25°C, unless otherwise noted.) (Note 1)

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 in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.

VDD, IN, PIN, SCK, SDA, STB, OUT to GND .........-0.3V to +6.0V

M_, S_, F_ to GND ....................................-0.3V to (V

OUT

+ 0.3V)

C1N, C2N to GND .......................................-0.3V to (V

IN

+ 0.3V)

C1P, C2P to GND ..-0.3V to greater of (V

OUT

+ 0.3V) or (VIN+ 0.3V)

PGND to GND .......................................................-0.3V to +0.3V

OUT Short Circuit to GND ..........................................Continuous

Continuous Power Dissipation (T

A

= +70°C)

24-Pin Thin QFN (derate 20.8mW/°C above +70°C)...1666mW

Operating Temperature Range ...........................-40°C to +85°C

Junction Temperature......................................................+150°C

Storage Temperature Range .............................-65°C to +150°C

Lead Temperature (soldering, 10s) .................................+300°C

PARAMETER CONDITIONS

UNIT

IN Operating Voltage 2.7 5.5 V

VDD Operating Range 2.7 5.5 V

Undervoltage-Lockout Threshold VIN rising or falling

V

Undervoltage-Lockout Hysteresis 50 mV

Output Overvoltage-Protection Threshold

V

OUT

rising

V

1.5x or 2x mode 4.0 6.5

IN + PIN No-Load Supply Current

10% setting, 1x mode, flash off

mA

TA = +25°C 0.7 5

IN + PIN Shutdown Supply Current

All LEDs off, STB = SDA =
SCK = V

DD

, I2C ready

T

A

= +85°C 0.8

µA

TA = +25°C 0.1 1

VDD Quiescent Current

All LEDs off, STB = SDA =
SCK = V

DD

, I2C ready

T

A

= +85°C 0.1

µA

Startup into 1x mode 0.5

Startup into 1.5x mode 1.0

Soft-Start Time

Startup into 2x mode 1.5

ms

LED Current Derating Function Start
Temperature

Temperature derating enabled

°C

LED Current Derating Function Slope

T

A

= +40°C to +85°C, temperature derating

enabled

%/°C

Default current setting, TA = +25°C -2

+2

LED Current SUB Output Accuracy
(Note 2)

D efaul t cur r ent setti ng , T

A

= - 40°C to + 85°C -5 +5

%

LED Current FLASH and MAIN Output
Accuracy

Default current setting (Note 2) -5

+5 %

M_, S_

Maximum M_, S_, F_ Sink Current

F_ 95

mA

M_, S_ 40 90

LED Dropout Voltage

F_ 40 90

mV

1.5x and 2x Mode Regulation Voltage

mV

1x to 1.5x and 1.5x to 2x Mode Transition
Threshold

V

M_

, VS_, V

F_

falling

mV

MIN TYP MAX

2.25 2.60

4.75 5.00 5.25

100% LED setting (Note 3)

28.5 30.0

0.35

+40

-1.7

±0.3

±0.3

100

150

100

MAX1707

Light-Management IC with Efficient 1x/1.5x/2x

Charge Pump for Backlight/Flash/RGB LEDs

_______________________________________________________________________________________ 3

Note 1: All devices are 100% production tested at TA= +25°C. Limits over the operating temperature range are guaranteed

by design.

Note 2: LED current specification includes both accuracy and matching tolerance.

Note 3: Dropout voltage is defined as the M2 or F3 to GND voltage at which current into M2 or F3 drops 10% from the value at 0.2V.

All other current regulators are tested functionally by the accuracy test and guaranteed for low dropout by design.

ELECTRICAL CHARACTERISTICS (continued)

(VIN= V

PIN

= VDD= 3.6V, V

GND

= V

PGND

= 0V, temperature derating disabled, TA= -40°C to +85°C, typical values are at TA=

+25°C, unless otherwise noted.) (Note 1)

PARAMETER CONDITIONS

UNIT

Input Voltage Mode Transition Hysteresis

mV

TA = +25°C

1

M_, S_, F_ Leakage in Shutdown

All LEDs off, STB =
V

DD T

A

= +85°C 0.1

µA

OUT Pulldown Resistance in Shutdown All LEDs off, STB = V

DD

5kΩ

Maximum OUT Current VIN ≥ 3.2V, V

OUT

= 3.9V

mA

1x mode (VIN - V

OUT

) / I

OUT

0.5 2.5

1.5x mode (1.5 x VIN - V

OUT

) / I

OUT

1.5 3.5Open-Loop OUT Resistance

2x mode (2 x V

IN

- V

OUT

) / I

OUT

2.0 4.1

Ω

Switching Frequency 1

MHz

SDA = 111xxx00 2

9

SDA = 111xxx01 2

18

SDA = 111xxx10 2

19

S1, S2, S3 (RGB) Full-Scale Ramp Time

SDA = 111xxx11 2

20

µs

Logic-Input High Voltage VDD = 2.7V to 5.5V

V

Logic-Input Low Voltage VDD = 2.7V to 5.5V 0.4 V

TA = +25°C

1

Logic-Input Current

V

IL

= 0V or VIH =

5.5V

T

A

= +85°C 0.1

µA

SDA Output Low Voltage I

SDA

= 3mA

0.4 V

I2C Clock Frequency 400 kHz

Bus- Fr ee Ti m e Betw een S TART and S TOP

t

BUF

1.3 µs

Hold Time Repeated START Condition t

HD_STA

0.6 0.1 µs

SCK Low Period t

LOW

1.3 0.2 µs

SCK High Period t

HIGH

0.6 0.2 µs

Setup Time Repeated START Condition t

SU_STA

0.6 0.1 µs

SDA Hold Time t

HD_DAT

0

µs

SDA Setup Time t

SU_DAT

50 ns

Setup Time for STOP Condition t

SU_STO

0.6 0.1 µs

Thermal Shutdown

°C

Thermal-Shutdown Hysteresis 20 °C

MIN TYP MAX

150

0.01

610

VDD / 2

0.01

0.03

100

-0.01

+160

MAX1707

Light-Management IC with Efficient 1x/1.5x/2x
Charge Pump for Backlight/Flash/RGB LEDs

4 _______________________________________________________________________________________

Typical Operating Characteristics

(TA = +25°C, unless otherwise noted.)

MAX1707 toc01

EFFICIENCY vs. SUPPLY VOLTAGE

DRIVING 4 MAIN LEDs

SUPPLY VOLTAGE (V)

EFFICIENCY (%)

4.33.93.53.1

20

10

0

30

40

50

60

70

80

90

100

2.7 5.55.14.7

SUPPLY VOLTAGE FALLING

30mA/LED

15mA/LED

1.9mA/LED

0

200

100

500

400

300

800

700

600

900

2.7 3.9 4.33.1 3.5 4.7 5.1 5.5

INPUT CURRENT vs. SUPPLY VOLTAGE
DRIVING LUMILEDS LXCL-PWF1 FLASH

MAX1707 toc02

SUPPLY VOLTAGE (V)

INPUT CURRENT (mA)

400mA

100mA

200mA

0

100

50

250

200

150

400

350

300

450

2.7 3.9 4.33.1 3.5 4.7 5.1 5.5

INPUT CURRENT vs. SUPPLY VOLTAGE

DRIVING 4 MAIN LEDs AND RGB LEDs

MAX1707 toc03

SUPPLY VOLTAGE (V)

INPUT CURRENT (mA)

SUPPLY VOLTAGE FALLING

30mA/LED

15mA/LED

1.9mA/LED

0

100

50

250

200

150

400

350

300

450

2.7 3.9 4.33.1 3.5 4.7 5.1 5.5

INPUT CURRENT vs. SUPPLY VOLTAGE

DRIVING 4 MAIN LEDs

MAX1707 toc04

SUPPLY VOLTAGE (V)

INPUT CURRENT (mA)

1.9mA/LED

SUPPLY VOLTAGE FALLING

30mA/LED

15mA/LED

0

100

50

250

200

150

400

350

300

450

2.7 3.9 4.33.1 3.5 4.7 5.1 5.5

INPUT CURRENT vs. SUPPLY VOLTAGE

DRIVING RGB LEDs

MAX1707 toc05

SUPPLY VOLTAGE (V)

INPUT CURRENT (mA)

SUPPLY VOLTAGE FALLING

30mA/LED

15mA/LED

1.9mA/LED

LED CURRENT MATCHING

vs. SUPPLY VOLTAGE

(MAIN AND RGB AT FULL CURRENT)

MAX1707 toc06

28.8

29.4

29.1

30.6

30.9

30.3

30.0

29.7

31.2

LED CURRENT (mA)

2.7 3.9 4.33.1 3.5 4.7 5.1 5.5
SUPPLY VOLTAGE (V)

4 WHITE
V

F

= 3.4V

RED
V

F

= 1.9V

GREEN
V

F

= 2V

BLUE
V

F

= 4.2V

LED CURRENT MATCHING

vs. SUPPLY VOLTAGE

(MAIN AND RGB AT 1.9mA/LED)

MAX1707 toc07

1.80

1.84

1.82

1.92

1.94

1.90

1.88

1.86

1.96

LED CURRENT (mA)

2.7 3.9 4.33.1 3.5 4.7 5.1 5.5
SUPPLY VOLTAGE (V)

4 WHITE
V

F

= 2.9V

RED
V

F

= 1.7V

GREEN
V

F

= 1.9V

BLUE
V

F

= 3.4V

0

10

5

20

15

25

30

-40 85

LED CURRENT vs. TEMPERATURE

MAX1707 toc08

TEMPERATURE (°C)

LED CURRENT (mA)

10-15 35 60

THERMAL DERATING OFF

THERMAL DERATING ON

4 MAIN OR 4 FLASH LEDs

MAX1707

Light-Management IC with Efficient 1x/1.5x/2x

Charge Pump for Backlight/Flash/RGB LEDs

_______________________________________________________________________________________ 5

50mV/div
(AC-COUPLED)

100mA/div

0

I

IN

50mV/div
(AC-COUPLED)

V

OUT

V

IN

1µs/div

OPERATING WAVEFORMS 1X MODE

MAX1707 toc09

50mV/div
(AC-COUPLED)

100mA/div

0

I

IN

50mV/div
(AC-COUPLED)

V

OUT

V

IN

1µs/div

OPERATING WAVEFORMS 1.5X MODE

MAX1707 toc10

50mV/div
(AC-COUPLED)
100mA/div

0

I

IN

50mV/div
(AC-COUPLED)

V

OUT

V

IN

1µs/div

OPERATING WAVEFORMS 2X MODE

MAX1707 toc11

200mA/div
0

0

I

IN

5V/div

1V/div

V

OUT

V

SDA

1ms/div

MAIN BACKLIGHT STARTUP WAVEFORM

MAX1707 toc12

200mA/div
0

0

I

IN

5V/div
1V/div

V

OUT

V

SDA

1ms/div

MAIN STARTUP WITH RGB ALREADY ON

MAX1707 toc13

200mA/div
0

0

I

IN

5V/div

1V/div

V

OUT

V

SDA

1ms/div

FLASH STARTUP WAVEFORM

MAX1707 toc14

Typical Operating Characteristics (continued)

(TA = +25°C, unless otherwise noted.)