CONSTANT VOLTAGE & CONSTANT CURRENT CONTROLLER TJ1052 FEATURES z z z z z z z Constant Voltage and Constant Current Control Low Voltage Operation Precision Internal Component Count Current Sink Output Stage Easy Compensation Low AC Mains Voltage Rejection Moisture Sensitivity Level 3 SOT-23 6L APPLICATION z Battery Chargers z Adapters ORDERING INFORMATION Device Package TJ1052SF6 TJ1052GSF6 SOT-23 6L DESCRIPTION TJ1052 is a highly integrated solution for SMPS applications requiring constant voltage and constant current mode. TJ1052 integrates one voltage reference, two operational amplifiers (with one output - common collectors), and a current sensing circuit. The voltage reference combined with one operational amplifier makes it an ideal voltage controller, and the other low voltage reference combined with the other operational amplifier makes it an ideal current limiter for output low side current sensing. The current threshold is fixed and precise. The only external components are : z A resistor bridge to be connected to the output of the power supply (adaptor, battery charger) to set the voltage regulation by dividing the desired output voltage to match the internal voltage reference value. z A sense resistor having a value and allowable dissipation power which need to be chosen according to the internal voltage threshold. TJ1052 is ideal for space shrunk applications such as adapters and battery chargers. Absolute Maximum Ratings (TA = 25℃, unless otherwise specified) CHARACTERISTIC SYMBOL MIN. MAX. UNIT DC Supply Voltage VCC - 20 V Input Voltage VIN -0.3 VCC V TOPR 0 85 ℃ TJ - 150 ℃ SYMBOL MIN. MAX. UNIT VCC 2.5 18 V Operating Free Air Temperature Range Maximum Junction Temperature Operating Conditions (TA=25℃) CHARACTERISTIC DC Supply Voltage Jul. 2010 – Preliminary -1- HTC CONSTANT VOLTAGE & CONSTANT CURRENT CONTROLLER TJ1052 Ordering Information Package Order No. Package Marking Supplied As Status SOT-23 6L TJ1052SF6 TJ1052 Reel Contact us SOT-23 6L TJ1052GSF6 TJ1052 Reel Contact us PIN CONFIGURATION VCC VSENSE ICTRL 6 5 4 1 2 3 VCTRL GND OUT SOT-23 6L Jul. 2010 – Preliminary PIN DESCRIPTION Pin No. SOT-23 6L Name Function 1 VCTRL Analog Input 2 GND Ground 3 OUT Current Sink Output 4 ICTRL Analog Input 5 VSENSE Analog Input 6 VCC Power Supply -2- HTC CONSTANT VOLTAGE & CONSTANT CURRENT CONTROLLER TJ1052 ELECTRICAL CHARACTERISTICS (TA=25℃ and VCC = +5V, unless otherwise specified) Symbol Parameters Condition Min. Typ. Max. Unit 2 mA Total Current Consumption ICC Total Supply Current - not taking the TA = 25℃ 1.1 output sinking current into account 0 < TA < 85°C 1.2 Voltage Control Loop GMV VREF IIBV Transconduction Gain (VCTRL). Sink Current Only (Note 1) Voltage Control Loop (Note 2) Input Bias Current (VCTRL) TA = 25℃ 0 < TA < 85°C 1 TA = 25℃ 1.198 0 < TA < 85°C 1.186 3.5 mA/mV 2.5 1.21 TA = 25℃ 200 0 < TA < 85°C 300 1.222 1.234 V nA Current Control Loop GMI VSENSE IIBI Transconduction Gain (ICTRL). Sink Current Only (Note 3) Current Control Loop (Note 4) TA = 25℃ 0 < TA < 85°C 1.5 Iout = 2.5 mA 196 0 < TA < 85°C 192 7 200 TA = 25℃ 30 0 < TA < 85°C 40 Low output voltage at 10 mA sinking TA = 25℃ 200 current 0 < TA < 85°C 500 Output Short Circuit Current. Output to TA = 25℃ 45 VCC. Sink Current Only 0 < TA < 85°C 60 Current out of pin ICTRL at -200mV mA/mV 204 208 mV μA Output Stage VOL IOS mV 90 mA Note 1. If the voltage on VCTRL (the negative input of the amplifier) is higher than the positive amplifier input (VREF=1.210V), and it is increased by 1mV, the sinking current at the output will be increased by 3.5mA. Note 2. The internal Voltage Reference is set at 1.210V (bandgap reference). The voltage control loop precision takes into account the cumulative effects of the internal voltage reference deviation as well as the input offset voltage of the trans-conductance operational amplifier. The internal Voltage Reference is fixed by bandgap, and trimmed to 0.5% accuracy at room temperature. Note 3. When the positive input at ICTRL is lower than -200mV, and the voltage is decreased by 1mV, the sinking current at the output will be increased by 7mA. Note 4. The internal current sense threshold is set to -200mV. The current control loop precision takes into account the cumulative effects of the internal voltage reference deviation as well as the input offset voltage of the trans-conduction operational amplifier. Jul. 2010 – Preliminary -3- HTC CONSTANT VOLTAGE & CONSTANT CURRENT CONTROLLER TJ1052 TYPICAL APPLICATION CIRCUIT TJ1052 VCC 1.210 V 6 + + R1 Rled RVC1 3 OUT - CVC1 1 VCTRL - 2 GND RIC1 4 ICTRL VOUT CIC1 + 200mV 5 R2 VSENSE RIC2 RSENSE IOUT Fig 1. Typical Adaptor or Battery Charger Application Using TJ1052 In the above application schematic, the device is used on the secondary side of a flyback adaptor (or battery charger) to provide an accurate control of voltage and current. The above feedback loop is made with an optocoupler. Jul. 2010 – Preliminary -4- HTC