LTC3230EUD-TRPBF中文资料

元器件交易网http://www.77cn.com.cn

Driver with Dual LDO

FEATURES

Low Noise Charge Pump Provides High Ef ciency with Automatic Mode Switching■ Multimode Operation: 1x, 1.5x, 2x■ Full-Scale Current Set Resistor■ Up to 125mA Total LED Current

■ Single Wire Enable/Brightness Control for Main and Sub Display LEDs

■ 32:1 Linear LED Brightness Control■ Dual 200mA Linear Regulators

■ Four 25mA Low Dropout Main LED Current Sources■ One 25mA Low Dropout Sub LED Current Source

■ Low Noise Constant Frequency Operation■ Low Shutdown Current: 3μA

■ Internal Soft-Start Limits Inrush Current During Start-Up and Mode Switching■ Open/Short LED Protection■ No Inductors■ 20-Lead 3mm × 3mm QFN Package

■

DESCRIPTION

The LTC®3230 is a low noise charge pump DC/DC converter

designed to drive 4 Main LEDs and 1 Sub LED, plus two 200mA linear regulators to provide additional system power. The LTC3230 charge pump requires only four small ceramic capacitors and one current set resistor to form a complete LED power supply and current controller.Built-in soft-start circuitry prevents excessive inrush cur-rent during start-up and mode changes. High switching frequency enables the use of small external capacitors. Main and Sub full-scale current settings are programmed by a single external resistor.

Charge pump ef ciency is optimized based on the voltage across the LED current sources. The part powers up in 1x mode and automatically switches to the next higher mode, 1.5x and subsequently 2x, whenever any LED current source approaches dropout.

Two 200mA linear regulators have independent enable and output voltage select pins. Each regulator can be set to one of three pre-selected output voltages with tri-level input pins. The regulators may be enabled independently of the charge pump.

The LTC3230 is available in a low pro le (0.75mm) 3mm × 3mm 20-lead QFN package.

APPLICATIONS

■

Multi-LED Driver and Dual LDO Supplies for Cell Phone, PDA, Digital Camera and PND Applications

including 6411531.

TYPICAL APPLICATION

C1

C2Ef ciency vs VIN Voltage

10090

EFFICIENCY (PLED/PIN) (%)

VIN807060504030201003

3.2

3.4

3.63.8VIN (V)

4

4.2

4.4

3230 TA01b

3230fa

1

元器件交易网http://www.77cn.com.cn

ABSOLUTE MAXIMUM RATINGS

(Notes 1-5)

PIN CONFIGURATION

TOP VIEW

C1MMLED3

C2M

15LDO114LDO2

21

13V112V211ENM

6SLED

7MLED1

8MLED2

910MLED4

C1P

CPO1ENLDO12ENLDO23RSET4ENS5

C2P

VIN

VIN, CPO .......................................................–0.3V to 6VENM, ENS, ENLDO1, ENLDO2,

V1, V2, LDO1, LDO2 ......................–0.3V to (VIN + 0.3V)ICPO (Note 2) ........................................................200mALD01, LD02 (Note 3) ............................................200mAMLED1-4, SLED, RSET..................................–0.3V to 6VOperating Ambient Temperature Range(Note 4) ....................................................–40°C to 85°CJunction Temperature ...........................................125°CStorage Temperature Range ...................–65°C to 150°C

UD PACKAGE

20-LEAD (3mm × 3mm) PLASTIC QFNTJMAX = 125°C, θJA = 68°C/W

EXPOSED PAD (PIN 21) IS GND, MUST BE SOLDERED TO PCB

ORDER INFORMATION

LEAD FREE FINISHLTC3230EUD#PBF

TAPE AND REELLTC3230EUD#TRPBF

PART MARKINGLCYB

PACKAGE DESCRIPTION

20-Lead (3mm × 3mm) Plastic QFN

TEMPERATURE RANGE–40°C to 85°C

Consult LTC Marketing for parts speci ed with wider operating temperature ranges.Consult LTC Marketing for information on non-standard lead based nish parts.

For more information on lead free part marking, go to: http://www.77cn.com.cn/leadfree/ For more information on tape and reel speci cations, go to: http://www.77cn.com.cn/tapeandreel/

ELECTRICAL CHARACTERISTICS The ● denotes the speci cations which apply over the full operating

PARAMETERVIN Operating VoltageIVIN Operating Current

ICPO = 0, 1x Mode

ICPO = 0, 1.5x ModeICPO = 0, 2x Mode

ENM = ENS = ENLD02 = ENLD01 = Low

●

temperature range, otherwise speci cations are at TA = 25°C. VIN = 3.6V, C1 = C2 = C4 = C5 = C6 = 1μF, RSET = 17.4k, ENM = ENS = high, ENLDO1 = ENLDO2 = low, unless otherwise noted.

CONDITIONS

●

MIN2.7

TYP0.481.21.63555

MAX5.5

UNITS

VmAmAmA

VIN Shutdown CurrentLED Current Ratio (ILED/IRSET)LED Dropout VoltageLED Current Matching

MLED/SLED Current, 5-Bit Linear DACUnused LED DetectionThreshold VoltageTest Current

9μAA/AmV%mAmA

MLED1, MLED2, MLED3, MLED4 and SLED Currents

Mode Switch Threshold, IMLED = 15mAAny Two MLED Outputs, IMLED = Full Scale1 ENM/ENS Strobe (FS)

31 ENM/ENS Strobes (FS/31)VCPO – MLEDLED Tied to CPO

●●

1000.525.50.860

20039

780178

mVμA

3230fa

2

元器件交易网http://www.77cn.com.cn

ELECTRICAL CHARACTERISTICS The ● denotes the speci cations which apply over the full operating

PARAMETER

CPO Short Circuit DetectionThreshold VoltageCharge Pump (CPO)1x Mode Output Voltage1.5x Mode Output Voltage2x Mode Output Voltage1x Mode Output Impedance1.5x Mode Output Impedance2x Mode Output ImpedanceClock FrequencyMode Switching DelaytEN

LDO1, LDO2Bias per 1 LDO

Additional DC Bias per LDOOutput Voltage AccuracyCurrent LimitLine RegulationLoad RegulationDropout VoltageV1, V2VILVIH

Shutdown Input CurrentActive Input CurrentENM, ENS, ENLDO1, ENLDO2VILVIHIIHIIL

ENM, ENS TimingtPWHtPWLtSDRSETVRSETIRSET

●●●●●●●

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