UNISONIC TECHNOLOGIES CO., LTD P1595 LINEAR INTEGRATED CIRCUIT 200KHZ, 1.5A PWM BUCK DC/DC CONVERTER DESCRIPTION The UTC P1595 is a monolithic integrated circuit intended for the use of a step-down DC/DC converter and it can drive a 1.5A load without additional transistors. The internal compensation makes feedback control having good line and load regulation without external design. The external shutdown function can be controlled by logic level and then enter the standby mode. The UTC P1595 features a guaranteed +3% tolerance on output voltage under specified input voltage and output load conditions. Thermal shutdown protection is designed to prevent over temperature operating from damage while current limit protection is against over current operating of the output switch. The switching frequency will be reduced if current limit function occurs and feedback voltage (VFB) drops below 0.5V. The UTC P1595 works at a 200kHz switching frequency so it allows smaller sized filter components. FEATURES * Output Voltage In Adjustable Output Version. * Adjustable Version Output Voltage Range: 0.75V ~ 22V With+3% Accuracy. * Short Circuit Protect * Fixed Switching Frequency: 200KHZ. * On/Off Shutdown Control Input. * Voltage Mode Non-Synchronous Pulse Width Modulation (PWM) Control. * Thermal-Shutdown And Current-Limit Protection. * Operating Voltage Can Be Up To 24V. * 1.5A Output Load Current. * Low Power Standby Mode. * Built-In Switching Transistor ORDERING INFORMATION Ordering Number P1595G-AB5-R Package SOT-89-5 Packing Tape Reel P1595G-AB5-R (1)Packing Type (1) R: Tape Reel (2)Package Type (2) AB5: SOT-89-5 (3)Green Package (3) G: Halogen Free and Lead Free www.unisonic.com.tw Copyright © 2015 Unisonic Technologies Co., Ltd 1 of 6 QW-R103-047.D P1595 LINEAR INTEGRATED CIRCUIT MARKING PIN CONFIGURATION VCC EN 5 4 1 2 3 SW GND FB PIN DESCRIPTION PIN NO. PIN NAME 1 2 3 4 5 SW GND FB EN VCC DESCRIPTION Switching Output Ground Feedback Voltage On/Off Pin Operating Voltage Input BLOCK DIAGRAM UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 2 of 6 QW-R103-047.D P1595 LINEAR INTEGRATED CIRCUIT ABSOLUTE MAXIMUM RATING (unless otherwise specified) PARAMETER SYMBOL RATINGS UNIT Supply Voltage VCC +26 V ON/OFF Pin Input Voltage VEN -0.3 ~ VCC V Feedback Pin Voltage VFB -0.3 ~ 12 V Operating Supply Voltage VOP 4.5~24 V Output Voltage to Ground VOUT -0.8 V Power Dissipation (Note 1) TA=25°C PD 690 mW Operating Temperature TOPR -20 ~ +125 °C Storage Temperature TSTG -65 ~ +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. THERMAL DATA PARAMETER SYMBOL RATINGS UNIT Junction to Ambient (Note 1) θJA 180 °C/W Junction to Case (Note 1) θJC 38 °C/W Note: 1. It’s Measured with the PCB copper area (need connect to VSS pins) of approximately 1.5 in2(Multi-layer) ELECTRICAL CHARACTERISTICS (TA=25°C, VCC=12V, ILOAD=0.2A, unless otherwise specified) PARAMETER Feedback Voltage Saturation Voltage Quiescent Current Feedback Bias Current Shutdown Supply Current Current Limit SW Pin Leakage Current SW pin=0V SW pin=-0.8V Oscillator Frequency Oscillator Frequency Circuit Protect of Short Max. Duty Cycle (ON) Min. Duty Cycle (OFF) EN Pin Logic Input Threshold Voltage EN pin Logic Input Current EN pin Input Current Thermal Shutdown Temp SYMBOL TEST CONDITIONS VFB IOUT=0.2A IOUT=1.5A, No outside circuit VSAT VFB=0V force driver on IQ VFB=1.2V force driver off IFB IOUT=0.1A ISD VEN=0V Pear current, No outside circuit I(LIMIT) VFB=0V force driver on No outside circuit ISW(LEAK) VFB=1.0V force driver off VCC=24V force driver off FOSC FSCP DC VIH VIL IH IL TSD TYP 0.750 MAX 0.773 UNIT V 1.2 1.5 V 4 -10 2 8 -50 10 mA nA μA 1.8 140 A -5 200 -50 μA 260 mA KHz (Adjustable) When VFB<0.5V 80 KHz VFB=1.2V force driver off VFB=0V force driver on High (regulator ON) Low (regulator OFF) VEN=2.5V (ON) VEN=0.3V (OFF) 0 100 1.2 1.2 20 -5 135 % % V V μA μA °C UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw MIN 0.728 0.5 2.0 3 of 6 QW-R103-047.D P1595 LINEAR INTEGRATED CIRCUIT TYPICAL APPLICATION CIRCUIT Adjustable Output Voltage Version R1 VOUT=VFB× 1 , VFB=0.75V. R2=0.75K~4K R2 Resistor select for output voltage setting VOUT 5V 3.3V 2.5V 1.8V 1.5V 1.3V 1.2V R2 1.2K 2K 2K 2K 2K 2K 2K L1 recommend value (VIN=12V, IOUT=1.5A,) VOUT 1.8 V L1 Value 22μH 2.5V 22μH R1 6.8K 6.8K 4.7K 3K 2K 1.5K 1.2K 3.3V 33μH 5V 33μH FUNCTION DESCRIPTIONS Pin Functions VCC It provides the IC switching regulator with positive input supply. This pin is used to supply the switching currents needed by the regulator and a suitable input bypass capacitor must be connected at this pin. GND Circuit ground. SW Internal switch. The voltage at this pin switches between (+VCC-VSAT) and approximately-0.5V, with a duty cycle of approximately VOUT / VCC. To minimize coupling to sensitive circuitry, you should minimize the PC board copper area connected to this pin. Feedback Senses the regulated output voltage to complete the feedback loop. EN Using logic level signals to allow the switching regulator circuit to be shutdown, which dropping the total input supply current to approximately 10uA. Shut the regulator down through pulling this pin below a threshold voltage of approximately 0.5V, turn the regulator on through pulling this pin above 2.0V (up to VCC MAX). UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 4 of 6 QW-R103-047.D P1595 LINEAR INTEGRATED CIRCUIT TYPICAL CHARACTERISTICS VOUT 2V/div VCC/EN 5V/div VCC/EN 5V/div VOUT 2V/div 1. Startup during power on 2. Low-frequency triangle wave control enable pin 2V/div 1V/div VCC=24V 1V 0 2V 0 0 2500 Time (500ms/div) 5000 EN 1V/div EN 1V/div VOUT 2V/div VOUT 2V/div 3. Control enable pin with power supply to normal UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 5 of 6 QW-R103-047.D P1595 LINEAR INTEGRATED CIRCUIT TYPICAL CHARACTERISTICS(Cont.) 4. Transient response with step load VCC=24V 50mV 50mV/div 50mV/div VCC=12V 0 -50mV 50mV 0 -50mV 0 1000 Time (200µs/div) 2000 0 500 Time (100µs/div) 1000 Efficiency (100%) 5. Efficiency 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 6 of 6 QW-R103-047.D