G1135P GLOBAL | Alldatasheet
Document overview
- Manufacturer or author: Provided By alldatasheet.com(free datasheet download site)
- PDF pages: 10
Technical content
Features
◆ 5% CV and CC Regulation at Universal AC input ◆ Primary-side Regulation Without TL431 and Opto-coupler ◆ Built-in High-Voltage Power MOS ◆ Programmable CV and CC Regulation ◆ Adjustable Constant Current and Output Power Setting ◆ Built-in Secondary Constant Current Control with Primary Side Feedback ◆ Built-in Primary winding inductance compensation ◆ Programmable cable drop compensation ◆ Built-in Leading Edge Blanking (LEB) ◆ Power on Soft-start ◆ Built-in adaptive current peak regulation ◆ Cycle-by-Cycle Current Limiting ◆ VDD Under Voltage Lockout with Hysteresis (UVLO) ◆ VDD OVP and VDD Clamp ◆ Pb-free DIP-7
Applications
◆ Cell Phone Charger ◆ Digital Cameras Charger ◆ LED Driver ◆ Small Power Adaptor ◆ Auxiliary Power for PC, TV etc. ◆ Linear Regulator/RCC Replacement G1135P is offered in DIP-7 package.
High Precision CC/CV Primary-Side PWM Power Switch Rev. 1.0 2 of 10 2. Products Information
2.1 Pin configuration
Fig.2. G1135P Pin Configuration
2.2 Output Power Table
Notes: 1. Maximum practical continuous power in an Adapter design with sufficient drain pattern as a heat sink, at 50℃ ambient. Higher output power is possible with extra added heat sink or air circulation to reduce thermal resistance. Pin Name I/O Description VDD P Power Supply COMP I Loop Compensation for CV Stability INV I The Voltage feedback from auxiliary winding. Connected to resistor divider from auxiliary winding reflecting output voltage. PWM duty cycle is determined by EA output and current sense signal at pin 4. CS I Current sense input. Connected to primary current sensing resistor. DRAIN O HV MOSFET Drain Pin. The Drain pin is connected to the primary lead of the transformer GND P Ground 85~264VAC Product Adapter1 G1135P 12W G1135P
High Precision CC/CV Primary-Side PWM Power Switch www.globalsemi-group.com 3 o f 1 0
2.3 Block diagram
Fig.3. G1135P Block Diagram 3. Absolute Maximum Ratings Notes: 1. Stress beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. Exposure to absolute maximum-rated conditions for extended periods may affect device reliability 2. Drain Pin Connected to 100mm2 PCB copper clad. Description Absolute Maximum Ratings VDD Voltage -0.3 to VDD_clamp HV MOSFET Drain Voltage -0.3 to BVdss VDD Zener Clamp Continuous Current 10 mA COMP Voltage -0.3 to 7V CS Input Voltage -0.3 to 7V INV Input Voltage -0.3 to 7V Max Operating Junction Temperature TJ 150℃ Min/Max Storage Temperature Tstg -55 to 150℃ Lead Temperature (Soldering, 10secs) 260℃ Package Dissipation Rating RθJA 2 75 ℃/W
High Precision CC/CV Primary-Side PWM Power Switch Rev. 1.0 4 of 10 4. Electrical Characteristics (TA = 25℃, VDD=16V, unless otherwise noted) Symbol Parameter Test Conditions Min Typ Max Unit Supply Voltage IVDD_ST Standby current VDD=13V -- 3.5 20.0 μA IVDD_OP Operation Current INV=2V,CS=0V, VDD =20V -- 0.9 1.5 mA UVLO_ON VDD Under Voltage Lockout Enter VDD falling 8.0 9.0 10.0 V UVLO_OFF VDD Under Voltage Lockout Exit VDD rising 13.5 14.5 16.0 V OVP Over voltage protection voltage Ramp up VDD until gate clock is off 27.0 28.0 29.0 V VDD_Clamp Maximum VDD operation voltage IDD=10mA 32.0 33.5 35.0 V Current Sense TLEB LEB time -- -- 500 -- ns VTH_OC Over current threshold -- 980 1000 1020 mV ZSENSE_IN Input Impedance -- 100 -- -- K Ω T_SS Soft start time -- -- 10 -- mS Frequency Section Freq_Max1 System Nominal switch frequency -- 55 60 65 KHz Freq_startup -- INV=0V,Comp=5V -- 22 -- KHz ᇞf/Freq Frequency jitter range -- -- +/-5 -- % Error Amplifier Section Vref_EA Reference voltage for EA -- 1.98 2.00 2.02 V Gain DC gain of the EA -- -- 60 -- dB ICOMP_Max Max. Cable compensation current INV=2V,COMP=0V -- 42 -- μA Power MOS Section BVdss MOSFET Drain-Source Breakdown Voltage -- 650 -- -- V Rdson On Resistance -- -- 4.4 -- Ω Notes: 1. Freq_Max indicates IC internal ma ximum clock frequency. In system application, the maximum operation frequency of 60KHz nominal occurs at maximum output power or the transition point from CV to CC.
High Precision CC/CV Primary-Side PWM Power Switch www.globalsemi-group.com 5 o f 1 0 5. CHARACTERIZATION
High Precision CC/CV Primary-Side PWM Power Switch Rev. 1.0 6 of 10 6. OPERATION DESCRIPTION Fig.4. G1135P Typical Application G1135P is a cost effective PWM power switch optimized for off-line low power AC/DC applications including battery chargers and adaptors. It operates in primary side sensing and regulation, thus opto-coupler and TL431 are not required. Proprietary built-in CV and CC control can achieve high precision CC/CV control meeting most adaptor and charger application requirements.
6.1 Startup Current and Start up Control
Startup current of G1135P is designed to be very low so that VDD could be charged up above UVLO threshold and starts up quickly. A large value startup resistor can therefore be used to minimize the power loss in application.
6.2 Operating Current
The Operating current of G1135P is as low as 0.9mA. Good efficiency is achieved with the low operating current together with Multi-mode control features.
6.3 Soft Start
G1135P features an internal soft start to minimize the component electrical over-stress during power on startup. As soon as VDD reaches UVLO (OFF), the control algorithm will ramp peak current voltage threshold gradually from nearly zero to normal setting of 1.00V. Every restart is a soft start.
6.4 CC/CV Operation
G1135P is designed to produce good CC/CV control characteristic as shown in the Fig.1. In charger applications, a discharged battery charging starts in the CC portion of the curve until it is nearly full charged and smoothly switches to operate in CV portion of the curve.
High Precision CC/CV Primary-Side PWM Power Switch www.globalsemi-group.com 7 o f 1 0 In an AC/DC adapter, the normal operation occurs only on the CV portion of the curve. The CC portion provides output current limiting. In CV operation, the output voltage is regulated through the primary side control. In CC operation mode, G1135P will regulate the output current constant regardless of the output voltage drop.
6.5 Principle of Operation
To support G1135P proprietary CC/CV control, system needs to be designed in DCM mode for flyback system (Refer to Fig.4). In the DCM flyback converter, the output voltage can be sensed via the auxiliary winding. During MOSFET turn-on time, the load current is supplied from the output filter capacitor CO. The current in the primary winding ramps up. When MOSFET turns off, the primary current transfers to the secondary at the amplitude of P SP S NI IN=× ( 1 ) The auxiliary voltage reflects the output voltage as shown in fig.5 and it is given by ()AUX AUX O S NVV V N=× + Δ (2) Where ΔV indicates the drop voltage of the output Diode. Fig.5. Auxiliary voltage waveform Via a resistor divider connected between the auxiliary winding and INV (pin 3), the auxiliary voltage is sampled at the end of the demagnetization and it is hold until the next sampling. The sampled voltage is compared with Vref (2.0V) and the error is amplified. The error amplifier output COMP reflects the load condition and controls the PWM switching frequency to regulate the output voltage, thus constant output voltage can be achieved. When sampled voltage is below Vref and the error amplifier output COMP reaches its maximum, the switching frequency is controlled by the sampled voltage thus the output voltage to regulate the output current, thus the constant output current can be achieved.
6.6 Adjustable CC point and Output Power
In G1135P, the CC point and maximum output power can be externally adjusted by external current sense resistor RS at CS pin as illustrated in Typical Application Diagram. The output power is adjusted through CC point change. The larger RS, the smaller CC
High Precision CC/CV Primary-Side PWM Power Switch Rev. 1.0 8 of 10 point is, and the smaller output power becomes, and vice versa as shown in Fig.6. Fig.6. Adjustable output power by changing RS
6.7 Operation switching frequency
The switching frequency of G1135P is adaptively controlled according to the load conditions and the operation modes. No external frequency setting components are required. The operation switching frequency at maximum output power is set to 60 KHz internally. For flyback operating in DCM, The maximum output power is given by _a x OM P S W PPL f I=× × × ( 3 ) Where LP indicates the inductance of primary winding and IP is the peak current of primary winding. Refer to the equation 3, the change of the primary winding inductance results in the change of the maximum output power and the constant output current in CC mode. To compensate the change from variations of primary winding inductance, the switching frequency is locked by an internal loop such that the switching frequency is de SW mag f T= × ( 4 ) Since Tdemag is inversely proportional to the inductance, as a result, the product LP and fSW is constant, thus the maximum output power and constant current in CC mode will not change as primary winding inductance changes. Up to +/-10% variation of the primary winding inductance can be compensated.
6.8 Frequency jitter for EMI improvement
The frequency jitter (switching frequency modulation) is implemented in G1135P. The oscillation frequency is modulated so that the tone energy is spread out. The spread spectrum minimizes the conduction band EMI and therefore eases the system design.
6.9 Current Sensing and Leading Edge Blanking
Cycle-by-Cycle current limiting is offered in G1135P current mode PWM control. The switch current is detected by a sense resistor into the CS pin. An internal leading edge blanking circuit chops off the sensed voltage spike at initial internal power MOSFET on state so that the external RC filtering on sense input is no longer needed. The PWM duty cycle is determined by the current sense input voltage and the EA output voltage.
High Precision CC/CV Primary-Side PWM Power Switch www.globalsemi-group.com 9 o f 1 0
6.10 Programmable Cable drop Compensation
In G1135P, cable drop compensation is implemented to achieve good load regulation. An offset voltage is generated at INV by an internal current flowing into the resister divider. The current is inversely proportional to the voltage across pin COMP, as a result, it is inversely proportional to the output load current, thus the drop due to the cable loss can be compensated. As the load current decreases from full-load to no-load, the offset voltage at INV will increase. It can also be programmed by adjusting the resistance of the divider to compensate the drop for various cable lines used.
6.11 Protection Control
Good power supply system reliability is achieved with its rich protection features including Cycle-by-Cycle current limiting (OCP), VDD clamp, Power on Soft Start, and Under Voltage Lockout on VDD (UVLO). VDD is supplied by transformer auxiliary winding output. The output of G1135P is shut down when VDD drops below UVLO (ON) limit and Switcher enters power on start-up sequence thereafter.
High Precision CC/CV Primary-Side PWM Power Switch R e v . 1 . 0 1 0 o f 1 0 7. Package Information DIP-7: Dimension in Millimeters Dimensions in Inches Symbol Min Max Min Max A 3.710 5.334 0.146 0.210 A2 2.921 4.953 0.115 0.195 B 0.350 0.650 0.014 0.026 B1 1.524(BSC) 0.06(BSC) C 0.200 0.360 0.008 0.014 D 9.000 10.160 0.354 0.400 E 6.096 7.112 0.240 0.280 E1 7.320 8.255 0.288 0.325 e 2.540(BSC) 0.1(BSC) L 2.921 3.810 0.115 0.150 E2 7.620 10.920 0.300 0.430 Data and specifications subject to change without notice. This product has been designed and qualified for Industrial Level and Lead-Free. Qualification Standards can be found on GS's Web site. Global Semiconductor HEADQUARTERS: Scotia Centre，4th Floor，P.O.Box 2804，George Town， Grand Cayman KY1-1112， Cayman Visit us at www.globalsemi-group.com for sales contact information.