UPSRB02G-AG6-R

UPSRB02_16 UTC | Alldatasheet

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UNISONIC TECHNOLOGIES CO., LTD UPSRB02 Preliminary LINEAR INTEGRATED CIRCUIT www.unisonic.com.tw 1 of 7 Copyright © 2016 Unisonic Technologies Co., Ltd QW-R103-079.b HIGH PRECISION CC/CV PRIMARY SIDE SWITCHING REGULATOR  DESCRIPTION The UTC UPSRB02 is a primary control unit for switch mode charger and adapter applications . The controlled variable is transferred by an auxiliary winding from the secondary to the primary side. The device uses Pulse Frequency Modulation (PFM) and Pulse Width Modulation (PWM) method to build discontinuous conduction mode (DCM) flyback power supplies. The UTC UPSRB02 operates in primary-side sensing and regulation. Opto-coupler and TL431 could be eliminated. It also eliminates the need of loop compensation circuitry while maintaining stability. The UTC UPSRB02 achieves high precision CV/CC regulation and high power efficiency. It offers comprehensive protection coverage with auto-recovery features including Cycle-by-cycle current limiting, output ov er voltage protection, V DD over voltage protection, feedback loop open protection, short circuit protection, leading edge blanking, OTP, VDD under voltage lockout, etc.  FEATURES SOT-26 * ±5% constant voltage regulation at universal AC input * Primary side control without TL431 and opto-coupler * High precision constant current regulation at universal AC input * Programmable CV and CC regulation * Eliminates control loop compensation circuitry * Flyback topology in DCM operation * Random frequency modulation to reduce system EMI * Driver BJT switch * Programmable cable drop compensation * Audio noise free operation * Improved dynamic response * Built-in leading edge blanking * Built-in primary winding inductance compensation * Open circuit protection * Output over voltage protection * VDD over voltage protection * Short circuit protection * Over temperature protection  ORDERING INFORMATION Ordering Number Package Packing UPSRB02G-AG6-R SOT-26 Tape Reel UPSRB02G-AG6-R (1)Packing Type (2)Package Type (3)Green Package (1) R: Tape Reel (2) AG6: SOT-26 (3) G: Halogen Free and Lead Freee

UPSRB02 Preliminary LINEAR INTEGRATED CIRCUIT UNISONIC TECHNOLOGIES CO., LTD 2 of 7 www.unisonic.com.tw Q W - R 1 0 3 - 0 7 9 . b  MARKING  PIN CONFIGURATION  PIN DESCRIPTION PIN NO. PIN NAME DESCRIPTION

1 VC Low pass filter capacitor for cable compensation

2 CS Current sense input. 3 BASE Base drive power BJT.

4 FB The voltage feedback from auxiliary winding

5 GND Ground

6 V DD Power supply

 BLOCK DIAGRAM Regulator &Ref Por VDD Logic core OVP4V + FB + -2V CV controller Base drive 0.4V BASE 0.5V LEB CC controller VC GND Tdemag detector CS I_drive Drop comp Dynamic response

UPSRB02 Preliminary LINEAR INTEGRATED CIRCUIT UNISONIC TECHNOLOGIES CO., LTD 3 of 7 www.unisonic.com.tw Q W - R 1 0 3 - 0 7 9 . b  ABSOLUTE MAXIMUM RATING PARAMETER SYMBOL RATINGS UNIT VDD Voltage VDD -0.3~30 V VC Voltage VC -0.3~7 V BASE Voltage VBASE -0.3~7 V CS Input Voltage V CS -0.3~7 V FB Input Voltage V FB -0.3~7 V Junction Temperature T J -40~150 °C Storage Temperature T STG -55~150 °C Lead Temperature (Soldering, 10 secs) T OPR 260 °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.  ELECTRICAL CHARACTERISTICS (TA=25°C, VDD=15V, if not otherwise noted) PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNIT Supply Voltage (VDD ) Section Start up Current I ST V DD=11V 1 3 μA Static Current I OP V DD=15V 400 500 μA Turn-off Threshold Voltage V TH(OFF) 6.0 6.8 7.6 V Turn-on Threshold Voltage V TH (ON) 11.5 12.5 13.5 V VDD Over Voltage Protection V DD_OVP 25 27 29 V Operating Voltage 25 V Current Sense Input Section LEB Time T LEB 0.5 μs Over Current Threshold V CS 400 450 500 mV OCP Propagation Delay T D_OC From OCP Comparator to Base Drive 100 nS Maximum Source Current to CS Pin I CS_MAX 41 45 49 μA FB Input Section Reference Voltage for Feedback Threshold VFB 1.98 2.00 2.02 V Minimum Pause T PAUSE_MIN 2.0 μs Maximum Pause T PAUSE_MAX 780 800 820 μs Maximum Cable Compensation Current ICABLE 27 μA BASE Drive Section Base Sourcing Maximum Current I OUT(SOURCE) 20 30 40 mA Base Sourcing Current After Pre-off I OUT(PRE) 0.5 1 1.5 mA Base Drive Low Side On Resistor R DSON_L 1 Ω

UPSRB02 Preliminary LINEAR INTEGRATED CIRCUIT UNISONIC TECHNOLOGIES CO., LTD 4 of 7 www.unisonic.com.tw Q W - R 1 0 3 - 0 7 9 . b  OPERATION DESCRIPTION The UTC UPSRB02 is a primary control unit for switch mode charger and adapter applications. It operates in primary-side sensing and regulation. Opto-coupler and TL43 1 could be eliminated. Proprietary built-in CV and CC control can achieve high precision CV/CC performance. It uses Pulse Frequency Modulation (PFM) and Pulse Width Modulation (PWM) method to build discontinuous conduction mode (DCM) flyback power supplies. Startup control The VDD pin of UTC UPSRB02 is connected to the line input through a resi stor. A large value startup resistor can be used to minimize the power loss in app lication because the start current of UTC UPSRB02 is very low. When the VDD voltage reaches VTH (ON), the internal startup circuit is disabled and the IC turns on. Operating Current The Operating current of UTC UPSRB02 is as low as 400 μA. Good efficiency and very low standby power can be achieved. Constant Voltage Operation The output voltage is defined by the transmission ratio between the secondary and auxiliary winding. The UTC UPSRB02 captures the auxiliary winding feedback voltage at FB pin and operates in constant-voltage (CV) mode to regulate the output voltage. The auxiliary voltage reflects the output voltage is given by: ˅˄ V∆+V×N N=V O S A AUX ( 1 ) Where △V indicates the drop voltage of the output diode. Figure2. Auxiliary voltage waveform Via a resistor divider connected between the auxiliary winding and FB, the VAUX is sampled at the Tsampling end and it is hold until the next sampling. The sampled voltage is compared with 2V reference voltage and the error is amplified. The error amplifier output reflects the load condition and controls the Toff time to regulate the output voltage, thus constant output voltage can be achieved. Constant Current Operation When the sampled voltage is below 2V reference voltage and the error amplifier output reaches its maximum, thus UTC UPSRB02 operates in constant-current (CC) mode. The CC point and maximum output power can be externally adjusted by external current sense resistor R cs. The larger Rcs, the sma ller CC point is, and the smaller output power becomes.

UPSRB02 Preliminary LINEAR INTEGRATED CIRCUIT UNISONIC TECHNOLOGIES CO., LTD 5 of 7 www.unisonic.com.tw Q W - R 1 0 3 - 0 7 9 . b  OPERATION DESCRIPTION (Cont.) Figure3. Adjustable output power by changing RCS Figure4. Secondary current waveform In CC operation, the CC loop control function of UTC UPSRB02 will keep a fixed proportion between secondary inductance de-magnetization time (Tdemag) and switching cycle time (Tsw). The fixed proportion is 1=T T SW demag ( 2 ) Thus the output current is given by: PK S P SW demag PK S P out I ×N N×4 1=T T ×I ×N N×2 1=I ( 3 ) Programmable Cable drop Compensation UTC UPSRB02 has a built-in cable voltage drop compensation to achieve good load regulation. An offset voltage is generated at FB pin by an internal current flowing into the resistor divider. The current is inversely proportional to the voltage of VC pin. As a result, it is inversely proportional to the output load current. The voltage drop across the cable is compensated by this offset voltage at FB pin. It can also be programmed by adjusting the resistance of the divider to compensate the drop for various cable lines used. Improve dynamic response At light or no load, an internal current ICS is flowing into CS pin. The current ICS is inversely proportional to the voltage of VC pin, the maximum current ICS is limited to ICS_max.

UPSRB02 Preliminary LINEAR INTEGRATED CIRCUIT UNISONIC TECHNOLOGIES CO., LTD 6 of 7 www.unisonic.com.tw Q W - R 1 0 3 - 0 7 9 . b  OPERATION DESCRIPTION (Cont.) At no load, the actual CS threshold is: VCS_no_Load=0.5-(ICS_MAX)×Rd ( V ) Current Sensing and Leading Edge Blanking Cycle-by-cycle current limiting is offered in UTC UPSRB02 . The switch current is detected by a sense resistor into the CS pin. When the power switch is turned on, a turn-on spike will occur on this resistor. A 500ns leading-edge blanking is built in to avoid false-termination of the switching pulse so that the external RC filtering is no longer needed. Drive BJT The driver is a push pull stage with the supply voltage V DD. It provides the driving current for the external power bipolar transistor. The output signal is current-limited to IOUT(SOURCE). Protection Control Good power supply system reliability is achieved with its comprehensive protection features including output over-voltage protection, V DD over voltage protection, OTP, feedback loop open protection, Cycle-by-cycle current limiting, short circuit protection, leading edge blanking and UVLO, etc. VDD is supplied by transformer auxiliary winding output. The output of UTC UPSRB02 is shutdown when VDD drops below VTH(OFF) and the power converter enters power on start-up sequence thereafter.

UPSRB02 Preliminary LINEAR INTEGRATED CIRCUIT UNISONIC TECHNOLOGIES CO., LTD 7 of 7 www.unisonic.com.tw Q W - R 1 0 3 - 0 7 9 . b  TYPICAL APPLICATION CIRCUIT UTC assumes no responsibility for equipment failures that result from u sing products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition rang es, 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 s ystems where malfunction of these products can be reasonably expected to result in personal injury. R eproduction in whole or in part is prohibited without the prior written consent of the copyright owner. T he information presented in this document does not form part of any quotation or contract, is believe d to be accurate and reliable and may be changed without notice.