HighPrecisionCC/CVPrimary-SidePWMPowerSwitch · DP2539A -2-/9 REV1.0 HighPrecisionCC/CVPrimary-SidePWMPowerSwitch GENERALINFORMATION PinConfiguration ThepinmapofDIP8packageisshownasbelow

DP2539A

www.depuw.com - 1 -/9 REV1.0

High Precision CC/CV Primary-Side PWM Power Switch

GENERAL DESCRIPTIONDP2539A is a high performance offline PWMpower switch for low power AC/DC charger andadapter applications. It operates in primary-sidesensing and regulation. Consequently,opto-coupler and TL431 could be eliminated. HighPrecision Constant Voltage (CV) and ConstantCurrent (CC) control are integrated as shown inthe figure below.In CC control, the current and output power settingcan be adjusted externally by the sense resistor Rsat CS pin. In CV control, multi-mode operations areutilized to achieve high performance and highefficiency. In addition, good load regulation isachieved by the built-in Cable Drop Compensation.Device operates in PFM in CC mode as well atlarge load condition and it operates in PWM withfrequency reduction at light/medium load. The chipconsumes very low operation current, it canachieve less than 75mW standby power.DP2539A offers comprehensive protectioncoverage with auto-recovery features includingCycle-by-Cycle current limiting, VDD Over VoltageProtection (VDD OVP), short circuit protection,built-in leading edge blanking, VDD under voltagelockout (UVLO), OTP, etc.High precision constant voltage (CV) and constantcurrent (CC) can be achieved by DP2539A.DP2539A is offered in DIP8 package.

FEATURES■ ± 5% Constant Voltage Regulation and

Current Regulation at Universal AC Input■ Primary Side Regulation (PSR) Without TL431

and Opto-coupler■ No Need for Control Loop Compensation■ Programmable CV and CC Regulation■ Multi-Mode PWM/PFM Operation■ Output Short Load Protection■ Less than 75mW Standby Power■ Built-in Line Voltage and Primary Winding

Inductance Compensation■ Built-in Adaptive Current Peak Regulation■ Programmable Cable Drop Compensation■ Audio Noise Free Operation■ Built-in Over Temperature Protection (OTP)■ Soft Gate Driver for Good EMI Performance■ Built-in Leading Edge Blanking (LEB)■ Cycle-by-Cycle Current Limiting■ VDD Under Voltage Lockout with Hysteresis

(UVLO)■ VDD OVP & Clamp

APPLICATIONSLow Power AC/DC offline SMPS for■ Cell Phone Charger■ Digital Camera Charger■ Small Power Adapter■ Auxiliary Power for PC, TV etc.■ Linear Regulator/RCC Replacement

TYPICAL APPLICATION

DP2539A



GENERAL INFORMATIONPin ConfigurationThe pin map of DIP8 package is shown as below.

Ordering InformationPart Number DescriptionDP2539A DIP8, Rohs, 50Pcs/Tube

Package Dissipation RatingPackage RJA (℃/W)DIP8 75

Absolute Maximum RatingsParameter ValueDrain Voltage (off state) -0.3 to 600VVDD Zener Clamp Voltage VDD_Clamp

VDD Clamp ContinuousCurrent 10 mA

CS Input Voltage -0.3 to 7VINV Input Voltage -0.3 to 7VMaximum Operating JunctionTemperature TJ 150 oC

Min/Max Storage TemperatureTstg -55 to 150 oC

Lead Temperature (Soldering,10secs) 260 oC

Note: Stresses beyond those listed under “absolute maximumratings” may cause permanent damage to the device. Theseare stress ratings only, functional operation of the device atthese or any other conditions beyond those indicated under“recommended operating conditions” is not implied. Exposureto absolute maximum-rated conditions for extended periodsmay affect device reliability.

Output Power Table (1)

Part Number 230VAC ± 15%(2) 85-265VACAdapter(3) Adapter(3)

DP2539A 18W 15WNote 1. TheMax. output power is limitedby junction temperatureNote 2. 230VACor100/115VACwithdoublersNote 3. Typical continuous power in a non-ventilated enclosed adapter with sufficient drain pattern as a heat sink at 50℃

ambient.

DP2539A



Marking Information

DPXXXX for product name;The A represents the version

XXXXXX The first X reresents the last year,2014 is 4; The second X represents the month, inA-L 12 letters;The third and fourth X on behalf of the date, 01-31 said; The last two X representsthe wafer batch code.

TERMINAL ASSIGNMENTSPin Num Pin Name I/O Description1 VDD P Power supply.2 NC - No connect.

3 INV I The voltage feedback from auxiliary winding. Connected to resistor dividerfrom auxiliary winding reflecting output voltage.

4 CS I Current sense input.5/6 Drain O The Power MOSFET Drain7/8 GND P Ground.

DP2539A



BLOCK DIAGRAM

RECOMMENDED OPERATING CONDITIONSymbol Parameter Min Max UnitVDD VDD Supply Voltage 11 27 VTA Operating Ambient Temperature -40 85 oC

DP2539A



ELECTRICAL CHARACTERISTICS(TA = 25OC, VDD=18V if not otherwise noted)Symbol Parameter Test Conditions Min Typ Max UnitSupply Voltage Section (VDD Pin)

IVDD_st Start-up current into VDDpin 2 20 uA

IVDD_Op Operation Current VINV=3V, VDD=20V 1 1.5 mAIVDD_standby Standby Current 0.5 1 mA

VDD_ONVDD Under VoltageLockout Exit 15 16.3 17.5 V

VDD_OFFVDD Under VoltageLockout Enter 8 9 10 V

VDD_OVP VDD OVP Threshold 28 30 32 V

VDD_ClampVDD Zener ClampVoltage I(VDD ) = 7 mA 32.5 34.5 36.5 V

Feedback Input Section (INV Pin)

VINV_REFInternal Error Amplifier(EA) Reference Input 1.97 2.0 2.03 V

VINV_SLPShort Load Protection(SLP) Threshold 0.7 V

TINV_Short Short Load Protection(SLP) Debounce Time 10 ms

VINV_DEMDemagnetizationComparator Threshold 25 mV

Toff_min Minimum OFF time 2 usToff_max Maximum OFF time 5 msF_min Minimum frequency 450 HzF_max Maximum frequency 72 KHz

ICable_max Maximum Cable Dropcompensation current 63 uA

Current Sense Input Section (CS Pin)

TLEB CS Input Leading EdgeBlanking Time 500 ns

Vcs(max) Current limiting threshold 490 500 510 mV

TD_OCP Over Current Detectionand Control Delay 100 ns

Over temperature ProtectionTSD Thermal Shutdown --- 165 -- °C

TRC Thermal Recovery 135 -- °C

Power MOSFET Section (Drain Pin)

VBR

Power MOSFET DrainSource BreakdownVoltage

600 V

RdsonStatic Drain-Source OnResistance 5 Ohm

DP2539A



CHARACTERIZATION PLOTS

…

DP2539A



OPERATION DESCRIPTIONDP2539A is a cost effective PWM power switchoptimized for off-line low power AC/DCapplications including battery chargers andadapters. It operates in Primary Side Regulation(PSR), thus opto-coupler and TL431 are notrequired. High precision CV and CC control canbe achieved to meet most small power chargerand adapter applications requirements.

Startup Current and Start up ControlStartup current of DP2539A is designed to bevery low (typically 2uA) so that VDD could becharged up above UVLO threshold level anddevice starts up quickly. A large value startupresistor can therefore be used to minimize thepower loss yet reliable startup in application.

Operating CurrentThe operating current of DP2539A is as low as1mA. Good efficiency is achieved by the lowoperating current together with extended burstmode control schemes at No/light loadconditions.

Primary Side CC/CV ControlDP2539A is designed to produce good CC/CVcontrol. In charger applications, a dischargedbattery charging starts in CC portion of the curveuntil it is nearly full charged and smoothlyswitched to operate in CV portion of the curve. Inan AC/DC adapter, the normal operation occursonly on the CV portion of the curve. The CCportion provides output current limiting.

Fig.1

As shown by Fig 1, when the PWM switching isoff the secondary side diode is conducted andthe auxiliary winding voltage is proportion to theoutput voltage. Via a resistor divider connected

between the auxiliary winding and INV (pin 3),the auxiliary voltage is sampled at the end of thedemagnetization and it is hold until the nextsampling. The sampled voltage is compared withVINV_REF (2.0V) and the error is amplified by aninternal Error Amplifier (EA). The internal EAoutput reflects the load condition and control thePWM switching frequency to regulate the outputvoltage, thus constant voltage (CV) can beachieved.When system enters over load condition, theoutput voltage falls down and the INV sampledvoltage should be lower than 2V internalreference which makes system enter CC Modeautomatically.

Multi Mode CV Operation for HighEfficiency

DP2539A is a multi-mode PSR controller. In CVmode, the controller changes the mode ofoperation by sampling INV voltage. Under themedium to large load conditions, the IC operatesin PWM mode, which improves the system audionoise performance. Under normal to light loadconditions, the IC operates in PFM mode toachieve high efficiency. The IC can achieve lessthan 75mW standby power, as shown in Fig.2

Fig.2

CC Operation Switching FrequencyThe switching frequency of DP2539A isadaptively controlled according to the loadconditions and the operation modes.For flyback operation in DCM, the maximumoutput power is given by

2

21

PSWPMAX IFLPo

Where Lp indicate the inductance of primarywinding and Ip is the peak current of primarywinding.

DP2539A



Refer to the equation above, the change of theprimary winding inductance results in the changeof the maximum output power and the constantoutput current in CC mode. To compensate thechange from variations of primary windinginductance, the switching frequency is locked byand internal loop such that the switchingfrequency is

DEMSW TF

21

Since TDEM is inversely proportional to theinductance, as a result, the product of Lp andFsw is constant, thus the maximum output powerand constant current in CC mode will not changeas primary winding inductance changes. Up to± 10% variation of the primary windinginductance can be compensated.

Adjustable CC Point and Output PowerIn DP2539A, the CC point and maximum outputpower can be externally adjusted by externalcurrent sense resistor Rs at CS pin as illustratedin typical application diagram. The larger Rs, thesmaller CC point is, and the smaller outputpower becomes, and vice versa as shown inFig.3.

Fig.3

Current Sensing and Leading EdgeBlanking

Cycle-by-Cycle current limiting is offered inDP2539A. The switch current is detected by asense resistor into the CS pin. An internalleading edge blanking circuit is built in. Duringthis blanking period (500ns, typical), thecycle-by-cycle current limiting comparator isdisabled and cannot switch off the GATE driver.

Audio Noise Free OperationDP2539A can provide audio noise free operationfrom full loading to zero loading.

Optimized Dynamic ResponseIn DP2539A, an optimized dynamic responsecontrol is integrated to improve system dynamic

response performance, which enables chargersystem to meet the USB charge requirements.

Programmable Cable DropCompensation

In DP2539A, cable drop compensation isimplemented to achieve good load regulation. Anoffset voltage is generated at INV pin by aninternal current flowing into the resistor divider.The current is proportional to the switching offtime, as a result, it is inversely proportional to theoutput load current, thus the drop due to thecable loss can be compensated. As the loadcurrent decreases from full-load to no-load, theoffset voltage at INV pin will increase. It can alsobe programmed by adjusting the resistance ofthe divider to compensate the drop for variouscable lines used.The percentage of maximum compensation is

%100V

R1//R2Icable_maxVoutV

INV_REF

ΔV is load compensation voltage and Vout isoutput voltage;For example: R1=3K Ω , R2=18K Ω , Thepercentage of maximum compensation is givenby

%1.8%1002V3K//18K63uA

VoutV

Over Temperature Protection (OTP)When the IC temperature is over 165 OC, the ICshuts down. Only when the IC temperature dropsto 135 OC, IC will restart.

Output Short Load ProtectionIn DP2539A, the output is sampled on INV pinand then compared with a threshold of UVP(0.7V typically) after an internal blanking time(10ms typical). When sensed INV voltage isbelow 0.7V, the IC will enter into Short LoadProtection (SLP) mode, in which the IC will enterinto auto recovery protection mode.

VDD OVP and Zener ClampWhen VDD voltage is higher than 30V (typical),the IC will stop switching. This will cause VDDfall down to be lower than VDD_OFF (typical 9V)and then the system will restart up again. Aninternal 34.5V (typical) zener clamp is integratedto prevent the IC from damage.

Soft Gate DriveDP2539A has a soft totem-pole gate driver withoptimized EMI performance. An internal 16Vclamp is added for MOSFET gate protection athigher than expected VDD input.

DP2539A



Package Dimension

Symbol Dimensions In Millimeters Dimensions In InchesMin Max Min Max

A 3.710 5.334 0.146 0.210A1 0.381 0.015A2 3.175 3.600 0.125 0.142B 0.350 0.650 0.014 0.026B1 1.524 (BSC) 0.06 (BSC)C 0.200 0.360 0.008 0.014D 9.000 10.160 0.354 0.400E 6.200 6.600 0.244 0.260E1 7.320 7.920 0.288 0.312e 2.540 (BSC) 0.1 (BSC)L 2.921 3.810 0.115 0.150E2 8.200 9.525 0.323 0.375

Documents

HighPrecisionCC/CVPrimary-SidePWMPowerSwitch · DP2539A -2-/9 REV1.0 HighPrecisionCC/CVPrimary-SidePWMPowerSwitch GENERALINFORMATION PinConfiguration ThepinmapofDIP8packageisshownasbelow