UNISONIC TECHNOLOGIES CO., LTD UCS16502S Advance LINEAR INTEGRATED CIRCUIT HIGH PERFORMANCE CURRENT MODE POWER SWITCH DESCRIPTION The UTC UCS16502S is an integrated PWM controller and Power MOSFET specifically designed for switching operation with minimal external components. The UTC UCS16502S is designed to provide several special enhancements to satisfy the needs, for example, Power-Saving mode for low standby power, Frequency Hopping , Constant Output Power Limiting , Slope Compensation ,Over Current Protection (OCP), Over Voltage Protection (OVP), Over Load Protection (OLP), Under Voltage Lock Out (UVLO), Over Temperature Protection (OTP), etc. IC will be shutdown or can auto-restart in situations. FEATURE * Internal Power MOSFET (650V) * Programming Gate Driver Capability * Frequency hopping for Improved EMI Performance. * Lower than 0.3W Standby Power Design * Linearly decreasing frequency to 26KHz during light load * Internal Soft start * Internal Slope Compensation * Constant Power Limiting for universal AC input Range ORDERING INFORMATION Ordering Number Lead Free Halogen Free UCS16502SL-D08-T UCS16502SG-D08-T UCS16502SG-S08-R * Gate Output Maximum Voltage Clamp(16V) * Over temperature protection * Overload protection * Over voltage protection * Leading edge blanking * Cycle-by-Cycle current limiting * Under Voltage Lock Out Package Packing DIP-8 SOP-8 Tube Tape Reel MARKING DIP-8 www.unisonic.com.tw Copyright © 2015 Unisonic Technologies Co., Ltd SOP-8 1 of 7 QW-R103-108.d UCS16502S Advance PIN CONFIGURATION PIN DESCRIPTION PIN NO. 1 2 3 4 5 6 7 8 PIN NAME VCC-G VCC FB CS DRAIN DRAIN GND GND LINEAR INTEGRATED CIRCUIT DESCRIPTION Supply voltage Supply voltage Feedback Current sense input Power MOSFET drain Power MOSFET drain Ground Ground BLOCK DIAGRAM Notes: OLP (Over Load Protection) OVP (Over Voltage Protection) OTP (Over Temperature Protection) OCP (Over Current Protection) UVLO (Under Voltage Latch-Out) LEB (Led Edge Blanking) UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 2 of 7 QW-R103-108.d UCS16502S Advance LINEAR INTEGRATED CIRCUIT ABSOLUTE MAXIMUM RATING (TA=25°C, unless otherwise specified) PARAMETER SYMBOL RATINGS UNIT Supply Voltage VCC 32 V Input Voltage to FB Pin VFB -0.3 ~ 6.5 V Input Voltage to CS Pin VCS -0.3 ~ 6.5 V Junction Temperature TJ +150 °C Operating Temperature TOPR -40 ~ +125 °C Storage Temperature TSTG -50 ~ +150 °C Note: Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. OPERATING RANGE PARAMETER Supply Voltage SYMBOL VCC RATINGS 10 ~ 24 UNIT V ELECTRICAL CHARACTERISTICS (TA＝25°C, VCC=15V, unless otherwise specified) PARAMETER SYMBOL SUPPLY SECTION Start Up Current IST Supply Current with switch IOP VDD Zener Clamp current vCLAMP UNDER-VOLTAGE LOCKOUT SECTION Start Threshold Voltage VTHD(ON) Min. Operating Voltage VCC(MIN) CONTROL SECTION Feedback Source Current IFB VFB Open Loop Voltage Level VFB_Open Burst-Mode Out FB Voltage VFB(OUT) Burst-Mode Enter FB Voltage VFB(IN) Normal initial Switching frequency F(SW) Power-Saving Duty Cycle DMAX Frequency Hopping FJ(SW) Frequency Variation VS VCC Deviation FDV Frequency Variation VS Temperature Deviation FDT Soft-Start Time TSOFTS PROTECTION SECTION OVP threshold VOVP OLP threshold VFB(OLP) Delay Time Of OLP TD-OLP OTP Threshold T(THR) CURRENT LIMITING SECTION Leading Edge Blanking Time tLEB Peak Current Limitation VCS Threshold Voltage For Valley VSENSE-L POWER MOS-TRANSISTOR SECTION Drain-Source Breakdown Voltage VDSS Turn-on voltage between gate and source VTH Drain-Source Diode Continuous Source Current IS Static Drain-Source On-State Resistance RDS(ON) Notes: 1. Pulse Test: Pulse width≤300μs, Duty cycle≤2%. 2. Essentially independent of operating temperature. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw TEST CONDITIONS VCC = VTHD(ON)-1V VFB= 3.5V IVDD=20mA MIN TYP MAX UNIT 28 2 0.8 30 15 1.8 32 μA mA V 18 6.5 20 8 22 9.5 V V VFB=0 VCS =0 VCS =0 VFB = 3.5V Before enter burst mode VFB=3.5V, VCS=0 60 20 240 5.4 1.8 1.6 65 70 78 ±4 VCC=10 ~ 20V T=-40 ~ 85°C 10 10 5 VFB=3.5V VCS=0 25 60 VFB=3.9V VFB=3.9V 0.5 VGS=0V, ID=250μA VDS=VGS, ID=250μA 650 2 VGS=10V, ID=0.8A 27 4.2 88 140 350 0.92 0.58 29 120 uA V V V kHz kHz % kHz % % ms V V ms °C 0.66 nS V V 4 0.7 18 V V A Ω 3 of 7 QW-R103-108.d UCS16502S Advance LINEAR INTEGRATED CIRCUIT FUNCTIONAL DESCRIPTION The internal reference voltages and bias circuit work at VCC> VTHD(ON), and shutdown at VCC<VCC(MIN). (1) Soft-Start When every IC power on, driver output duty cycle will be decided by inter-slope voltage VSOFTS and VCS on current sense resistor at beginning. After the whole soft-start phase end, and driver duty cycle depend on VFB and VCS. The relation among VSOFTS, VFB and VOUT as followed Fig.3. Furthermore, soft-start phase should end before VCC reach VCC(MIN) during VCC power on. Otherwise, if soft-start phase remain not end before VCC reach VCC(MIN) during VCC power on, IC will enter auto-restart phase and not set up VOUT. Fig.3 Soft-start phase (2) Switching Frequency Set The maximum switching frequency is set to 65kHz. Switching frequency is modulated by output power POUT during IC operating. At no load or light load condition, most of the power dissipation in a switching mode power supply is from switching loss on the MOSFET transistor, the core loss of the transformer and the loss on the snubber circuit. The magnitude of power loss is in proportion to the number of switching events within a fixed period of time. So lower Switching frequency at lower load, which more and more improve IC’s efficiency at light load. At from no load to light load condition, The IC will operate at from Burst mode to Reducing Frequency Mode. The relation curve between fSW and POUT/POUT(MAX) as followed Fig.4. 70 1%~100% Load @ 115 & 230 Vac 60 FSW (KHz) 55 115V 40 230V 25 10 1% 19% 9% 30% 100% POUT/POUT(max) Fig.4 The relation curve between fSW and relative output power POUT/ POUT (MAX) UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 4 of 7 QW-R103-108.d UCS16502S Advance LINEAR INTEGRATED CIRCUIT FUNCTIONAL DESCRIPTION(Cont.) (3) Internal Synchronized Slope Compensation Built-in slope compensation circuit adds voltage ramp onto the current sense input voltage for PWM generation, this greatly improves the close loop stability at CCM and prevents the sub-harmonic oscillation and thus reduces the output ripple voltage. (4) Frequency Hopping For EMI Improvement The Frequency Hopping is implemented in the IC; there are two oscillators built-in the IC. The first oscillator is to set the normal switching frequency; the switching frequency is modulated with a period signal generated by the 2nd oscillator. The relation between the first oscillator and the 2nd oscillator as followed Fig.5. So the tone energy is evenly spread out, the spread spectrum minimizes the conduction band EMI and therefore eases the system design in meeting stringent EMI requirement. Fig.5 Frequency Hopping (5) Constant Output Power Limit When the primary current, across the primary wind of transfer, reaches the limit current, the output GATE drive will be turned off after a small propagation delay tD. This propagation delay will introduce an additional current proportional to tD×VIN/Lp. Since the propagation delay is nearly constant regardless of the input line voltage VIN. Higher input line voltage will result in a larger additional current and hence the output power limit is also higher than that under low input line voltage. To compensate for this output power limit variation across a wide AC input range, the threshold voltage is adjusted by adding a positive ramp. This ramp signal rises from 0.6V to 0.9V, and then flattens out at 0.9V. A smaller threshold voltage forces the output GATE drive to terminate earlier. This reduces the total PWM turn-on time and makes the output power equal to that of low line input. This proprietary internal compensation ensures a constant output power limit for a wide AC input voltage range (90VAC to 264VAC). (6) Protection section The IC takes on more protection functions such as OLP, OVP and OTP etc. In case of those failure modes for continual blanking time, the driver is shut down. At the same time, IC enters auto-restart, VCC power on and driver is reset after VCC power on again. OLP After power on, IC will shutdown driver if over load state occurs for continual TD-OLP. OLP case as followed Fig.6. The test circuit as followed Fig.8. OVP OVP will shutdown the switching of the power MOSFET whenever VCC>VOVP. The OVP case as followed Fig.7. the test circuit as followed Fig.9. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 5 of 7 QW-R103-108.d UCS16502S Advance LINEAR INTEGRATED CIRCUIT FUNCTIONAL DESCRIPTION(Cont.) Fig.6 OLP case Fig.7 OVP case 15V VDD 470u 33n 500Ω/1W 15V VCC IC3 8 1 470u 2 33n 2.5V Fig.8 OLP test circuit Drain 7 UTC UCS16502S 3 6 4 5 VOVP VCC Fig.9 OVP test circuit OTP OTP will shut down driver when junction temperature TJ>T(THR) for continual a blanking time. (7) Driver Output Section The driver-stage drives the gate of the MOSFET and is optimized to minimize EMI and to provide high circuit efficiency. This is done by reducing the switch on slope when reaching the MOSFET threshold. This is achieved by a slope control of the rising edge at the driver’s output. The output driver is clamped by an internal 15V Zener diode in order to protect power MOSFET transistors against undesirable gate over voltage. (8) Inside power switch MOS transistor Specific power MOS transistor parameter is as “POWER MOS TRANSISTOR SECTION” in electrical characteristics table. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 6 of 7 QW-R103-108.d UCS16502S Advance LINEAR INTEGRATED CIRCUIT TYPICAL APPLICATION CIRCUIT Fig.10 UTC UCS16502S Typical Application Circuit UTC assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all UTC products described or contained herein. UTC products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 7 of 7 QW-R103-108.d