Datasheet SP7683 Datasheet (Sipex)

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Page 1

Advanced

SP7683

Four Channel Charge Pump Regulator LED Driver

FEATURES

LED1

EN/ PWM

LED3

LED4

LED2

SET

SP7683

16 Pin QFN

C1N

■ 2.7V to 5.5V Input Voltage Range

■ Up to 4 LEDS with matching currents

■ LEDs can be Driven from the Charge

Pump Output

■ 1X and 1.5X Mode Charge Pump

■ High Efficiency Operation

■ 1.2 MHz Switching Frequency

■ Programable LED Drive Capabliity

On/Off

■ PWM Dimming Control

■ Low 0.5µA Shutdown Current

■ Soft-Start Limits Inrush Current

■ Output Overvoltage Protection

■ Thermal Shutdown Protection

■ QFN (4mm x 4mm) package

Now Available in Lead Free Packaging

APPLICATIONS

■ Smart Phones

■ Cell Phones

■ PDA's

■ Digital Cameras

■ MP3 Players

■ Other Portables

The SP7683 is high efficiency Charge Pump which regulates up to four white LEDs with matching current. Based on the supply headroom available for the four precision current sinks, SP7683 automatically switches between 1X and 1.5X modes. The part powers up in 1X mode, with low quiescent current of 70uA (typ) and remains in 1X mode as long as the LED current has not decreased by more than 0.5%. If the current decreases, then it switches into 1.5X mode where it regulates the lowest of the LED cathode voltages to 0.1V. Other features include soft-start, over current protection, overvoltage protection and thermal shutdown at 140°C. Offered in 4X4 16 pin QFN.

TYPICAL APPLICATION SCHEMATIC

4x4 mm

C2P

C2N

MODE

C1P

8765

OUT

GND

DESCRIPTION

D1 D2

R2 1M

R3 100k

0.1uF

SP7683

2 10 11

C4 1uF

Vin

270k

C1 1uF

100k

GND

LED_EN

D3 D4

SP7683

50k - 200k

7 1

C5 1uF

R5 10k

R10 100k

SET

C2 1uF

Page 2

These are stress ratings only and functional operation of the device at these ratings or any other above those indicated in the operation sections of the

specifications below is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability.

Voltage to GND.....................................................0.5V

SET

IN, OUT, EN1, EN2 to GND................................-0.3V to 6V

SET, LED1, LED2, LED3, LED4 to GND -0.3V to IN+0.3V

C1N, C2N to GND...........................................-0.3 to IN+1V

OUT Short Circuit to GND.........................Continious

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

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

Lead Temperature (Soldering, 10 sec)............300°C

C1P, C2P to GND - 0.3V to greater than IN+1 or OUT+1V

ELECTRICAL CHARACTERISTICS

ABSOLUTE MAXIMUM RATINGS

Unless otherwise specified: V otherwise noted.

RETEMARAPNIMPYTXAMSTINUSNOITIDNOC

egatloVtupnI7.25.5V

tnerruCtnecseiuQ5.3 Am

tnerruCnwodtuhS5.5.1AµV

TUO

emITno-nruT052005sµ

)1etoN(oitaR

gnihctaMtnerruCDEL3-8.03% sDEL2ynA

egatloVedohtaCDEL5.0V4D-1DsDEL

edoMFFOnitnerruC10.01AµV

ycneuqerFrotallicsO7.2.15.1zHMV

egatloVecnerefeRBF772.013.243.VI

tnerruCniPBF10.05.0AµV

ecnatsiseRtuptuO

EDOM

siseretsyH03Vm

tnerruCniP10.05.0AµV

Note 1: Output current Multiplication Ratio (I

performance characteristics @ page 4 and page 5 of SP7614 datasheet.

= 3.6V, MODE = 0V, ILX = 0mA, TA = -40°C to +85°C, typical values at 27º unless

TUO

tnerruCdaoLmumixaM002AmV

noitacilpitluMtnerruCtuptuO

041002062I

TES

TUO

V0=

V1=

V,V5.5-V3=

Aµ001=

TUO

V,V0=MWP/

V,V2.4=

V,edoMX5.1

V6.3=

TUO

V,Aµ001=

V3.=

DEL

V5.5-V7.2=

V,Am02=

TUO

851

smhO

37 daolAm001,EDOMX1

egatloVdlohserhT152.15.1VVNIgnillaf

V52.1=

EDOM

hgiHcigoLMWP/ELBANE6.1V

woLcigoLMWP/ELBANE4.0V

tnerruCniPMWP/elbanE10.05.0AµV

) is not linear. For actual ratio and I

LED/ISET

V2.4=MWP/

please refer to typical

LED

,V6.3=

V5.5=

noitaluger%09nihtiwBF

I,6.3=

Aµ001=

TUO

daolAm001,EDOMX5.1

EDOMX5.1,V6.3=

Page 3

Unless otherwise specified: V noted.

RETEMARAPNIMPYTXAMSTINUSNOITIDNOC

=3.6V, MODE=0V, ILX=omA, TA =-40°C to +85°C, typical values at 27º unless otherwise

ELECTRICAL CHARACTERISTICS

"egatloVnO"FFO/NOniM

)2etoN(hgiHcigoL

"egatloVffO"FFO/NOxaM

)2etoN(woLcigoL

Note 2: "ON" is V "OFF" is V

ON/OFF

where I

> 20mA @ V

LED1

< 1µA @ V

LED1

#NIPEMANNIPNOITPIRCSED

TES

I.pihsnoitalereht

2FFO/NO.)4DEL-1DEL(lortnocFFO/NODEL

33DEL

TUO

.desutonfi

44DEL

TUO

.desutonfi

5N1C.lanimretevitageN1roticapaCgniylF

6P2ClanimreTevitisoP2roticapaCgniylF

TUO

5.0V

= 0.3V.

LED1

> 0.3V.

LED1

V(002=

DEL

nwodtuhSecnadepmI

PIN DESCRIPTION

VneewtebdehcattarotsiserpullupA

TUO

V-

TUO

R/)

TESI

TES

ybtnerructuptuoehtstesnipsihtdna

VsetalugerpmupegrahcehtedoMX5.1nI.4DELrofnoitcennoCedohtaC

TUO

ottcennoC.Vm051sisegatlov4DELdna,3DEL,2DEL,1DELfotsewolehttaht

VsetalugerpmupegrahcehtedoMX5.1nI.3DELrofnoitcennoCedohtaC

TUO

ottcennoC.Vm051sisegatlov4DELdna,3DEL,2DEL,1DELfotsewolehttaht

hgiH.roticapacFµ1ahtiwDNGotssapyB.sDELllafosedonaehtsevirD.tuptuO

8DNGnoitcennoCdnuorG

9P1C.lanimretevitsoP1roticapaCgniylF

01V

DNGotroticapaccimarecFµ1ahtiwssapyB.tupniegatlovylppuS

1Xa,V52.1nahtretaergsiedomVnehW.nipmargorpedompmupegrahC

11V

EDOM

egatlovA.edom5.1Xotsehctiwspmupegrahc,esiwrehtO.desusipmupegrahc

egrahcrofdlohserhtniVehtsmargorptiucricnoitacilppalacipytninwohsredivid

.gnihctiwsedompmup

21BF

.ecnereferVm603lanretninahtiwderapmocsinipsiht

foegatlovehT.noitalugeregatlovrotnerructuptuorofnipkcabdeefehtsisihT

31N2C.lanimretevitageN2roticapaCgniylF

41MWP/NE.tupnilortnocgnimmidMWP/elbanE

VsetalugerpmupegrahcehtedoMX5.1nI.1DELrofnoitcennoCedohtaC

TUO

511DEL

TUO

.desutonfi

612DEL

TUO

.desutonfi

ottcennoC.Vm051sisegatlov4DELdna,3DEL,2DEL,1DELfotsewolehttaht

VsetalugerpmupegrahcehtedoMX5.1nI.2DELrofnoitcennoCedohtaC

TUO

ottcennoC.Vm051sisegatlov4DELdna,3DEL,2DEL,1DELfotsewolehttaht

Page 4

EN/PWM

MODE

1.25V

MODE COMP

Voltage

Reference

306mV

OUT

COMP

600 kHz

Clock

Manager

Mode Control

BLOCK DIAGRAM

Start-up

and

Charge

Pump

Switches

GND

C1P

C1N

C2P

C2N

OUT

ON/OFF

Logic

Control

LED1

LDO Current

Regulator

LED3

LED2

LED4

Page 5

CIRCUIT DESCRIPTION

The SP7683 is comprised of two stages. First is a regulated change pump to convert the input voltage V is a low dropout current matching regulator that provides stable identical currents in all four

into a stable output voltage or current depending on the mode used. The second stage

channels to drive LED1 - LED4. The first stage can drive an additional four LEDs that are connected in parallel to the V additional diodes for current matching.

pin. It is recommended to use resistors in series with these

OUT

The SP7683 provides dimming control for the LEDs, with a constant ratio of brightness between them. It can also be used to turn off the LEDs completely.

The Charge Pump

The regulated charge pump can operate in two modes 1X V over the entire battery voltage range. The input voltage trip point at which the charge pump will

and 1.5X V

to optimize efficiency

automatically switch from a 1X mode to 1.5X mode is defined by an external voltage divider connected to V a switching cycle. To achieve better efficiency it is recommended that the V V

IN_TRIP = VF

connected to V

+ 0.31 + MI

pin. Cycle-by-cycle regulation ensures that no mode change occurs during

MODE

IN_TRIP

OUT

where VF is the LED forward voltage and (M) is the number of LEDs

OUT

is the output resistance. I

. R

LED

OUT

is the current per LED.

LED

is set at

The charge pump may be configured in voltage mode or as a current source. When used as a voltage source the output voltage is determined by an external resistive divider connected to FB pin as: V

= (1+R10/R5)*V

OUT

(see Figure 2) where V

= 0.31V.

When used as a current source the current in one single LED (D5 - D8) may be set by series resistor RS as I resistors. Three-wire LED modules with internal series resistors can also be driven in this way.

LED

= V

/ R

The current in the remaining LEDs will track based on the ballast

The flying capacitors C1 an C2 of the charge pump control the tade-off between the output voltage ripple and the output current capability. Decreasing the flying capacitors will reduce the output voltage ripple because less charge will be delivered to the output capacitor. However, smaller flying capacitors lead to larger output resistance, thus decreasing the output current handling capability and circuit efficiency. We recommend using ceramic capacitors in the range of 1µF -

4.7µF with low ESR, which helps reduce peak-to-peak output ripple and reduce high frequency noise spikes.

Dimming control can be achieved by applying a PWM control signal to the EN/PWM pin. The brightness of the LEDs is controlled by varying the duty cycle of the PWM signal. PWM repetition rate from 60Hz - 700Hz. A repetition rate of at least 60Hz is required to prevent visible flickering. Applying a logic low signal to EN/PWM control input turns of the device resulting in supply current below 1µA and high impedance state of the V

OUT

pin.

Page 6

CIRCUIT DESCRIPTION

The Low Dropout Regulator

The low dropout regulator provides matched currents into four LEDs. The current in the LED can be programmed by an external resistor connected between the V I

= 200*(V

LED

voltage value.

OUT

- 0.5)/R

where the 200 is the Output Current Multiplying Ratio and 0.5 is I

SET

OUT

and I

SET

pins.

SET

Board Layout and Grounding

To obtain the best performance from the SP7683, a printed circuit board with ground plane is required. High quality, low series resistance ceramic 0.1µF bypass capacitors should be used at the V

and V

located as close to the part as possible. The traces connecting the pins to these capacitors should

pins (pin 10 and 7). These capacitors and flying capacitors C1 and C2 must be

OUT

be made as short and wide as possible.

Vin

C1 1uF

GND

LED_EN

Vin

C1 1uF

GND

100k

R4 270k

R5 270k

R2 1M

R3 100k

0.1uF

R3 1M

R4 100k

0.1uF

SP7683

C4 1uF

SP7683

10 11

C4 1uF

D1 D2

10 11

D1 D2

SP7683

D3 D4

50k - 200k

D3 D4

50k - 200k

C5 1uF

D5 D6 D7R7D8

7 1

C5 1uF

R5 20

D5 D6 D7 D8

C2 1uF

R8R6

C2 1uF

D9 D10 D11 D12

LED_EN

Page 7

4X Øº

PACKAGE: 16 PIN QFN

SEATING PLANE

16 Pin QFN JEDEC MO-220 VGGC-4

SYMBOL

A 0.8 0.9 1 A1 0 0.02 0.05 A2 0 0.65 1 A3

E2 7.4 7.8 8.2

D2 2.2 2.4 2.6

E2 2.2 2.4 2.6

L 0.45 0.55 0.65 K 0.2 - b 0.25 0.3 0.35 e

Note: Dimensions in (mm)

Variation

MIN NOM MAX

0.20 REF

4.00 BSC

0.65 BSC

NX L

NX K

NX b

16 PIN QFN

Page 8

ORDERING INFORMATION

Part Number Operating Temperature Range Package Type

SP7683ER .................................................. -40°C to +85°C ............................................ 16 Pin 4 x 4mm QFN

SP7683ER/TR ............................................ -40°C to +85°C ............................................ 16 Pin 4 x 4mm QFN

Available in lead free packaging. To order add “-L” suffix to part number. Example: SP7683ER/TR = standard; SP7683ER-L/TR = lead free

/TR = Tape and Reel

Pack quantity is 2500 for QFN.

CLICK HERE TO ORDER SAMPLES

Corporation

ANALOG EXCELLENCE

Sipex Corporation

Headquarters and Sales Office

233 South Hillview Drive Milpitas, CA 95035 TEL: (408) 934-7500 FAX: (408) 935-7600

Sipex Corporation reserves the right to make changes to any products described herein. Sipex does not assume any liability arising out of the application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor the rights of others.

Datasheet SP7683 Datasheet (Sipex)

Specifications and Main Features

Frequently Asked Questions

User Manual