Light Management Unit POWER MANAGEMENT Features Input supply

The Datasheet Archive - 100 Million Datasheets from 7500 Manufacturers.

Light Management Unit POWER MANAGEMENT Features Input supply

Datasheet Thumbnail

Top Searches for this datasheet

SC623
Light Management Unit
POWER MANAGEMENT Features
Input supply voltage range 3.0V 5.5V Charge pump modes 1.5x Four programmable current sinks with steps from 0.5mA 25mA Flash 400mA flash mode, 250mA continuous spotlight Charge pump frequency 250kHz SemWiresingle wire interface 75kbit/s Backlight current accuracy ±1.5% typical Backlight current matching ±0.5% typical Programmable fade-in/fade-out main backlight External flash control sync with camera Optional flash time Automatic sleep mode (LEDs 100A shutdown current 0.1A (typical) Ultra-thin package 0.6mm Fully WEEE RoHS compliant
Charge Pump, LEDs, 400mA Flash LED, SemWireInterface Description
SC623 high efficiency charge pump driver using Semtech's proprietary mAhXLifetechnology. Performance optimized single-cell Li-ion battery applications. charge pump provides backlight current conjunction with four matched current sinks. also supply continuous bursted current flash using dedicated flash driver current sink. load supply conditions determine whether charge pump operates 1.5x, mode. optional fading feature that gradually adjusts backlight current provided simplify control software. flash-timeout feature disables flash active longer than second. SC623 uses proprietary SemWiresingle wire interface. interface controls functions device, including backlight flash currents. single wire implementation minimizes microcontroller interface counts. flash/spotlight output triggered either SemWire interface dedicated pin. sleep mode, device reduces quiescent current 100A while continuing monitor serial interface. Total current reduces 0.1A shutdown.
Applications
Cellular phone backlighting flash backlighting flash
Typical Application Circuit
MAIN BACKLIGHT VBAT 2.2F SemWire Interface Flash Control SWIF FLEN VOUT COUT 4.7F
FLASH
SC623
GREF AGND PGND C1C1 2.2F
C2C2 2.2F
Patents: 6,504,422; 6,794,926 June 2007
2007 Semtech Corporation
SC623
Configuration Ordering Information
Device
C1C2+ VOUT
Package
MLPQ-UT-20 Evaluation Board
SC623ULTRT(1)(2) SC623EVB
C2PGND
VIEW
SWIF
Notes: Available tape reel only. reel contains 3,000 devices. Available lead-free package only. Device WEEE RoHS compliant.
AGND
MLPQ-UT-20; 3x3, LEAD 35°C/W
Marking Information
yyww xxxx
yyww Date Code xxxx Semtech
GREF
FLEN
SC623
Absolute Maximum Ratings
-0.3 +6.0 VOUT -0.3 +6.0 C1+, -0.3 (VOUT 0.3) Voltage Other Pins -0.3 (VIN 0.3) VOUT Short Circuit Duration Continuous Short Circuit Duration Continuous Protection Level(1) (kV)
Recommended Operating Conditions
Ambient Temperature Range (°C) VOUT VOUT 5.25 Voltage Difference between LEDs
Thermal Information
Thermal Resistance, Junction Ambient(2) (°C/W) Maximum Junction Temperature (°C) +150 Storage Temperature Range (°C) +150 Peak Reflow Temperature (10s 30s) (°C) +260
Exceeding above specifications result permanent damage device device malfunction. Operation outside parameters specified Electrical Characteristics section recommended. NOTES: Tested according JEDEC standard JESD22-A114-B. Calculated from package still air, mounted 4.5", layer with thermal vias under exposed JESD51 standards.
Electrical Characteristics
Unless otherwise noted, +25°C Typ, +85°C Max, TJ(MAX) 3.0V 4.2V, CIN= 2.2F, COUT 4.7F (ESR 0.03), 1.2V(1)
Parameter
Supply Specifications Shutdown Current
Symbol
Conditions
Units
IQ(OFF)
Shutdown, 4.2V Sleep mode, SWIF Charge pump mode, backlights
4.65 5.85 5.85
Total Quiescent Current
Charge pump 1.5x mode, backlights Charge pump mode, backlights
Fault Protection Output Short Circuit Current Limit Over-Temperature Flash Mode Safety Timer(2) IOUT(SC) TOTP tFL(MAX) Flash sink active 0.75 VOUT shorted 1.00 1.25
SC623
Electrical Characteristics (continued)
Parameter Fault Protection (continued)
Charge Pump Over-Voltage Protection VOVP VUVLO Undervoltage Lockout VUVLO-HYS VOUT open circuit, VOUT VOVP rising threshold Decreasing
Symbol
Conditions
Units
Charge Pump Electrical Specifications
Maximum Total Output Current Backlight Current Setting Flash Current Setting Backlight Current Accuracy Backlight Current Matching Flash Current Accuracy Mode 1.5x Mode Falling Transition Voltage 1.5x Mode Mode Hysteresis 1.5x Mode Mode Falling Transition Voltage Mode 1.5x Mode Hysteresis Current Sink Off-State Leakage Current Pump Frequency IOUT(MAX) IBL_ACC IBL-BL IFL_ACC TRANS1x VHYST1x TRANS1.5x VHYST1.5x IBLn fPUMP 3.4V, active currents, VOUT(MAX) 4.0V Nominal setting thru Nominal setting 3.7V, 12mA, 25°C 3.7V, 12mA(3) 3.7V, 400mA, 25°C IOUT 40mA, IBLn 10mA, VOUT 3.2V IOUT 40mA, IBLn 10mA, VOUT 3.2V IOUT 40mA, IBLn 10mA, VOUT 4.0V(4) IOUT 40mA, IBLn 10mA, VOUT 4.0V(4) VBLn 4.2V 3.2V -3.5 3.27 ±1.5 ±0.5 +3.5
2.92
SC623
Electrical Characteristics (continued)
Parameter Symbol Conditions Units
Digital Electrical Specifications (FLEN, SWIF) Input High Threshold Input Threshold Input High Current Input Current SemWire Rate SemWire Start-up Time(5) SemWire Disable Time(6) SemWire Data Latch Delay(7) fSWIF tDIS 5.5V 3.0V 5.5V 5.5V kbit/s
Notes: voltage difference between LEDs. Once tripped, flash output will remain disabled until FLEN cycled reset serial interface. Current matching equals [IBL(MAX) IBL(MIN] [IBL(MAX) IBL(MIN)]. Test voltage VOUT 4.0V relatively extreme voltage force transition during test. Typically VOUT 3.2V white LEDs. SemWire start-up time minimum period that SWIF must held high enable part before commencing communication. SemWire disable time minimum period that SWIF must pulled shut part down. SemWire data latch delay maximum duration after communication ended before register updated.
SC623
Typical Characteristics
Battery Current LEDs) 25mA Each
VOUT=3.66V, IOUT=100mA, 25°C
Battery Current LEDs) 12mA Each
VOUT=3.50V, IOUT=48mA, 25°C
Battery Current (mA)
Battery Current (mA)
Backlight Efficiency LEDs) 25mA Each
VOUT=3.66V, IOUT=100mA, 25°C
Backlight Efficiency LEDs) 12mA Each
VOUT=3.50V, IOUT=48mA, 25°C
Efficiency
Efficiency
Battery Current LEDs) 5.0mA Each
VOUT=3.33V, IOUT=20mA, 25°C
Backlight Efficiency LEDs) 5.0mA Each
VOUT=3.33V, IOUT=20mA, 25°C
Battery Current (mA)
Efficiency
SC623
Typical Characteristics (continued)
Flash Current 300mA
VOUT=3.58V 25°C
Flash Current 400mA
VOUT=3.39V 25°C
Flash Current (mA)
Flash Current (mA)
Spotlight Current 50mA
VOUT=3.02V 25°C
Spotlight Current 250mA
VOUT=3.50V 25°C
Spotlight Current (mA)
Spotlight Current (mA)
SC623
Typical Characteristics (continued)
Output Short Circuit Current Limit
VOUT=0V, VIN=4.2V, 25°C
Flash Mode Safety Timer
VIN=3.7V, 25°C
VOUT (1V/div)
VFLEN (5V/div)
VOUT (2V/div)
IOUT (100mA/div) (200mA/div)
Time (1ms/div)
Time (200ms/div)
Output Open Circuit Protection
VIN=3.7V, 25°C VBL1 (500mV/div) VFLEN (5V/div)
Flash Current Pulse
IFL=400mA, VIN=3.7V, VOUT=3.7V, 25°C
VOUT (2V/div)
VOUT (2V/div)
IBL1 (20mA/div)
(200mA/div)
Time (200s/div)
Time (40ms/div)
SC623
Descriptions
Name
C2PGND AGND GREF FLEN SWIF VOUT C1THERMAL
Function
Negative connection bucket capacitor requires 2.2F capacitor connected Ground high current charge pump Flash driver Current sink output flash LED(s) Current sink output main backlight leave this open unused Current sink output main backlight leave this open unused Current sink output main backlight leave this open unused Current sink output main backlight leave this open unused Analog ground connect ground separate from PGND current Ground reference connect ground Control flash LED(s) high SemWire single wire interface used enable/disable device internal registers (refer Register SemWire Interface sections) Unused terminate Unused terminate Unused terminate Unused terminate Charge pump output anode pins should connected this requires 4.7F capacitor PGND Positive connection bucket capacitor requires 2.2F capacitor connected C2Positive connection bucket capacitor requires 2.2F capacitor connected C1Battery voltage input connect with 2.2F capacitor PGND Negative connection bucket capacitor requires 2.2F capacitor connected Thermal heatsinking purposes connect ground plane using multiple vias connected internally
SC623
Block Diagram
C120
VOUT
mAhXLifeFractional Charge Pump (1x, 1.5x,
VOUT PGND
SWIF
SemWireDigital Interface Logic Control
Oscillator Current Setting
FLEN
GREF
Bandgap Reference
AGND
SC623
Applications Information
General Description
This design optimized handheld applications supplied from single Li-Ion cell includes following features: connected between pins shown typical application circuit diagram. These capacitors should equal value, with minimum capacitance 2.2F support charge pump current requirements. device also requires 2.2F capacitor 4.7F capacitor VOUT minimize noise support output drive requirements. Capacitors with ceramic dielectric strongly recommended their superior temperature voltage characteristics. capacitors should used their temperature coefficients make them unsuitable this application.
high efficiency fractional charge pump that supplies power LEDs Four matched current sinks that control backlighting current, with 0.5mA 25mA flash output that provides 400mA momentary current 250mA continuous spotlight current SemWire single wire interface that provides control device functions
Backlight Current Sinks
backlight current SemWire interface. current regulated values between 0.5mA 25mA. step size varies depending upon current setting. Between 0.5mA 12mA, step size 0.5mA. step size increases settings between 12mA 15mA settings greater than 15mA. This feature allows finer adjustment dimming functions current setting range coarse adjustment higher current settings where small current changes visibly noticeable brightness. backlight current sinks have matched currents, even when there variation forward voltages LEDs. 1.2V supported when input voltage 3.0V. Higher mis-match supported when higher than 3.0V. current sink outputs compared lowest output used setting voltage regulation VOUT pin. This done ensure that sufficient bias exists LEDs, including flash LED. backlight LEDs default state upon powerup. backlight applications using less than four LEDs, unused output must left open unused driver must remain disabled. When writing Backlight Enable Control register, zero must written corresponding unused output.
High Current Fractional Charge Pump
backlight flash outputs supported high efficiency, high current fractional charge pump output VOUT pin. charge pump multiplies input voltage 1.5, times. charge pump switches fixed frequency 250kHz 1.5x modes disabled mode save power improve efficiency. mode selection circuit automatically selects 1.5x mode based circuit conditions. Circuit conditions such input voltage, high output current, high voltage place higher demand charge pump output. higher numerical mode needed momentarily maintain regulation VOUT during intervals high demand, such high current flash droop during supply voltage transient. charge pump responds these momentary high demands, setting charge pump optimum mode (1x, 1.5x 2x), needed deliver output voltage load current while optimizing efficiency. Hysteresis provided prevent mode toggling. charge pump requires bucket capacitors ripple operation. capacitor must connected between pins other must
SC623
Applications Information (continued)
Backlight Quiescent Current
quiescent current required operate four backlights reduced 1.5mA when backlight current 4.0mA less. This feature results higher efficiency under light-load conditions. Further reduction quiescent current will result from using fewer than four LEDs.
Shutdown State
device disabled when SWIF low. registers reset default condition when SWIF low.
Sleep Mode
When LEDs off, sleep mode activated. This reduced current mode that helps minimize overall current consumption turning clock charge pump while continuing monitor serial interface commands.
Fade-In Fade-Out
Backlight brightness automatically fade-in when current increase fade-out when current decrease. When enabled with current setting, current will step through each incremental setting between values. result visually smooth change brightness with rate fade that step.
SemWire Single Wire Interface Functions
device functions controlled SemWire single wire interface. interface described detail SemWire Interface section datasheet.
Flash Spotlight Current Sink
single output current sink provided drive both flash spotlight functions. flash mode, this current sink provides 400mA flash array parallel LEDs. Flash current settings 50mA increments from 50mA 400mA. FLEN directly triggers FLASH function when pulled high, wired enable software control serial interface. spotlight mode, output 250mA continuous current. Settings available 50mA increments from 50mA 250mA. Continuous operation above 250mA recommended high power dissipation.
Protection Features
SC623 provides several protection features safeguard device from catastrophic failures. These features include:
Output Open Circuit Protection Over-Temperature Protection Charge Pump Output Current Limit Float Detection
Flash Spotlight Safety Timer
safety timer disables flash spotlight output current sink sink remains active extended period. timer protects SC623 from high power dissipation that cause overheating. timer's default state timer disabled serial interface allow continuous output current spotlight mode. safety timer affects only will turn sink after period second. timer reset either forcing FLEN resetting Flash/Spotlight control bits interface.
Output Open Circuit Protection Over-Voltage Protection (OVP) provided VOUT prevent charge pump from producing excessively high output voltage. event open circuit VOUT, charge pump runs open loop voltage rises limit. operation hysteretic, meaning charge pump will momentarily turn until VOUT sufficiently reduced. maximum threshold 6.0V, allowing ceramic output capacitor rated 6.3V with fear over-voltage damage.
SC623
Applications Information (continued)
Over-Temperature Protection Over-Temperature (OT) protection circuit helps prevent device from overheating experiencing catastrophic failure. When junction temperature exceeds 160°C, device goes into thermal shutdown with outputs disabled until junction temperature reduced. register information retained during thermal shutdown. Charge Pump Output Current Limit device also limits charge pump current VOUT pin. When VOUT shorted ground, typical output current limit 300mA. current limiting triggered output under-voltage lockout below output returns normal when short removed VOUT above 2.5V. Above 2.5V, typical current limit 300mA applies when current sink typical current limit applies when current sink Float Detection Float detect fault detection feature current sink outputs. output programmed enabled open circuit fault occurs current sink output, that output will disabled prevent sustained output condition from occurring resulting open loop. Float detect ensures device protection does ensure optimum performance. Unused outputs must disabled prevent open circuit fault from occurring.
SC623
Applications Information (continued)
Layout Considerations
layout diagram Figure illustrates proper two-layer layout SC623 supporting components. Following fundamental layout rules critical achieving performance specified Electrical Characteristics table. following guidelines recommended when developing layout:
Place bypass decoupling capacitors CIN, COUT close device possible. charge pump current passes through VIN, VOUT, bucket capacitor connection pins. Ensure that connections these pins make wide traces that resistive drop each connection minimized. thermal should connected ground plane using multiple vias ensure proper thermal connection optimal heat transfer.
Make ground connections solid ground plane shown example layout (Figure ground layer feasible, following groupings should connected: PGND CIN, COUT AGND Ground ground plane available, PGND AGND should routed back negative battery terminal separate signals using thick traces. Joining ground returns terminal prevents large pulsed return currents from mixing with low-noise return currents.
VOUT
COUT
VOUT
Figure Layer
PGND
SC623
SWIF
AGND
GREF
Figure Recommended Layout Figure Layer
FLEN
SC623
Register
Address Reset Value
0x00
Description
Backlight Current Control Backlight Enable Control Flash/Spotlight Control
0x00
FADE_1
FADE_0
FADE_EN
BL_4
BL_3
BL_2
BL_1
BL_0
0x01
0(1)
0(1)
0(1)
0(1)
BLEN_4
BLEN_3
BLEN_2
BLEN_1
0x00
0x02
0(1)
0(1)
0(1)
FLTO
FL_2
FL_1
FL_0
FL/SPLB
0x10
Notes: always write these bits
Register Definitions
Backlight Current Control Register (0x00)
This register used currents backlight current sinks, well enable fade step rate. These current sinks need enabled Backlight Enable Control register active. FADE[1:0] These bits used rise/fall rate between backlight currents follows:
FADE_1
FADE_0
Fade Feature Rise/Fall Rate (ms/step)
value value bits BL[4:0] rate 32ms step. backlight level cannot written during ongoing fade operation, ongoing fade operation cancelled resetting fade bit. Clearing fade during ongoing fade operation changes backlight current immediately value BL[4:0]. number counts complete fade operation equals difference between backlight values increment decrement BL[4:0] bits. fade cleared, current level will change immediately without fade delay. rate fade changed dynamically, even while fade operation active, writing values FADE_1 FADE_0 bits. total fade time determined number steps between backlight values, multiplied rate fade ms/step. longest elapsed time full scale fade-out backlight nominally 1.024 seconds when default interval 32ms used.
number steps changing backlight current will equal change binary count bits BL[4:0]. FADE_EN This used enable disable fade feature. When fade function enabled backlight current set, backlight current will change from current
SC623
Register Definitions (continued)
BL[4:0] These bits used current backlight current sinks. enabled backlight current sinks will sink same current, shown Table Table Backlight Current Control Bits
BL_4 BL_3 BL_2 BL_1 BL_0
Enable Control Register (0x01)
This register used enable backlight current sinks. BLEN[4:1] These bits used enable current sinks (active high, default low). BLEN_4 Enable backlight BLEN_3 Enable backlight BLEN_2 Enable backlight BLEN_1 Enable backlight When enabled, current sinks will carry current backlight current control bits BL[4:0], shown Table Flash/Spotlight Control Register (0x02) This register used configure flash time-out feature, flash spotlight current, select flash spotlight current ranges. FLTO This used enable flash safety time-out feature. default state enabled with FLTO this set, device will turn flash after nominal period ways re-enable flash function after safety time-out are: Pull FLEN re-enable flash function Clear re-write FL[2:0]
Backlight Current (mA)
10.5 11.5
SC623
Register Definitions (continued)
FL[2:0] These bits used current flash current sink when configured flash spotlight FL/SPLB bit. Bits FL[2:0] flash spotlight current, shown Table Table Flash/Spotlight Control Bits
FL_2
FL_1
FL_0
SPLB
Flash/Spotlight Current (mA)
300(1) 350(1) 400(1) 400(1) 400(1) 400(1) 400(1)
FL/SPLB This used select either flash spotlight current ranges. this set, current sink used drive flash maximum duration 500ms current range will high (flash) current range. this cleared, current sink used drive continuous spotlight lower current current range will lower (spotlight) current range, shown Table
Note: When continuously, device reach temperature limit with 300mA higher.
SC623
SemWire Interface
Semwire Interface Functions
SWIF write-only single wire interface. provides capability address registers control device functionality. protocol using this interface described following subsections. Driving SWIF SWIF should driven GPIO from system microcontroller. output level configured either push-pull driver (TTL CMOS levels) open drain driver with external pull-up resistor. Enabling Device SWIF must pulled from high period greater than (tEN) enable device into sleep state. sleep state, device bandgap active, UVLO monitoring active, serial interface monitored communication. Automatic Sleep State both backlight flash current sinks disabled, device automatically enters sleep state order minimize current draw from battery. When sleep mode, charge pump oscillator both disabled. Disabling Device SWIF must pulled from high period greater than 10ms (tDIS) order shut down device. this state device remains disabled until SWIF pulled high period greater than 1ms. registers return default state, resetting bits zero except FLT0, which defaults one.
SemWire Communication Protocol Timing
following step communication sequence controls device functions when device enabled. SWIF toggled duration high duration order enable oscillator. oscillator turned sleep state minimize quiescent current. Sample SWIF toggled duration high duration. During this time, device samples rate determines rate which register address data values that follow will arrive. sample rate least times rate ensuring robust communication synchronization. Start SWIF pulled duration, which starts communication with target register. Address next bits address target register first, last. Data next bits data written target register first, last. Standby After last data sent, SWIF pulled high durations return device standby before another data write take place. LEDs disabled, device will back sleep mode. NOTE: rate must host controller rate that between minimum maximum frequencies listed Electrical Characteristics section.
SC623
SemWire Interface (continued)
Single Write Operation
Device Disabled Device Enabled Into Sleep Sample Register Address Data
Resume high Sleep bits LEDs Min. Device Disabled when tDIS
Start
tDIS
Concatenated Write Operation
Sample Register Address Data (Repeated) Sample
Start
Start
concatenate write operations, repeat Sample Start after previous sequence shown.
SC623
Outline Drawing MLPQ-UT-20
DIMENSIONS INCHES MILLIMETERS
.020 .000 .024 .002 0.50 0.00 0.60 0.05 (.006) .006 .008 .010 .114 .118 .122 .061 .067 .071 .114 .118 .122 .061 .067 .071 .016 .012 .016 .020 .003 .004 (0.1524) 0.15 0.20 0.25 2.90 3.00 3.10 1.55 1.70 1.80 2.90 3.00 3.10 1.55 1.70 1.80 0.40 0.30 0.40 0.50 0.08 0.10
INDICATOR (LASER MARK)
SEATING PLANE
NOTES: CONTROLLING DIMENSIONS MILLIMETERS (ANGLES DEGREES).
COPLANARITY APPLIES EXPOSED WELL TERMINALS 1.90 190mm.
SC623
Land Pattern MLPQ-UT-20
DIMENSIONS INCHES (.114) .083 .067 .067 .016 .004 .008 .031 .146 MILLIMETERS (2.90) 2.10 1.70 1.70 0.40 0.10 0.20 0.80 3.70
NOTES:
CONTROLLING DIMENSIONS MILLIMETERS (ANGLES DEGREES). THIS LAND PATTERN REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES MET. THERMAL VIAS LAND PATTERN EXPOSED SHALL CONNECTED SYSTEM GROUND PLANE. FAILURE COMPROMISE THERMAL AND/OR FUNCTIONAL PERFORMANCE DEVICE.
Contact Information
Semtech Corporation Power Management Products Division Flynn Road, Camarillo, 93012 Phone: (805) 498-2111 Fax: (805) 498-3804 www.semtech.com

Light Management Unit POWER MANAGEMENT Features Input supply

Top Searches for this datasheet

Other recent searches