PT1115 Datasheet | Powtech

1.5A Constant Voltage and Constant Current Buck with Cable Resistance pensation GENERAL DESCRIPTION The PT1115 is a low cost, high efficiency pulse-width modulated (PWM) switching mode buck converter with both constant voltage (CV) and constant current (CC) functions. The input voltage of PT1115 can be as high as 35V at which the over-voltage protection is triggered. The Vin pin is capable of sustaining 48V that further improves the reliability of the PT1115 under the conditions of hot swap and surging voltages. In the CC mode, the output current variation is less than ±4% of the nominal value which can be set up to 1.5A by the current sensing resistor. In the CV mode, the feedback voltage is controlled within ±2%. In the PT1115, output cable wire resistance pensation, is implemented to offset up to 600m V voltage drop along the cable. The amount of pensation can be programmed by an external resistor based on the cable resistance. The PT1115 based system can achieve better EMI performance because of spread spectrum. The PT1115 provides protections of over-voltage, under-voltage lockout, short-ground, peak current limit, and over-temperature shutdown to guarantee safe applications under extreme conditions. The PT1115 is available in a SOP-8 package Features z z z z z z z z z z z z z z z z 7.2~35V operating input voltage range 700 k Hz fixed switching frequency. PWM control ±4% output current accuracy in the CC mode 0.5~1.5A output current set by a small current sensing resistor ±2% feedback voltage accuracy in the CV mode Cable wire resistance pensation. Input and output over voltage protection (OVP) Short-ground protection Cycle-by-cycle switching peak current limit Soft start for power-up 150o C over temperature shutdown under-voltage lockout (UVLO) Frequency dithering to reduce EMI 100m W no load power consumption SOP-8 package APPLICATIONS z z z z Automobile chargers Step-down DC/DC conversion LCD TVs Larger current battery charging...