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 ±10% of the nominal value which can be set up to 1.5A by the current sensing resistor. In the CV mode, the output voltage is controlled within ±2% of 5V. In the PT1115, output cable wire resistance compensation is implemented to offset up to 300mV voltage drop along the cable. The amount of compensation can be programmed by an external capacitor based on the cable resistance.
The switching frequency of the PT1115 can also be programmed by an external resistor. With user optimized frequency, together with the inherent small output ripple voltage and spread spectrum technique, the PT1115 based system can achieve great EMI performance. The PT1115 provides protections against 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 ESOP-8 and QFN16 packages
7.0~35V operating input voltage range
50k~250kHz switching frequency programmed by an external resistor.
± 10% output current accuracy in the CC mode
0.5~ 1.5A output current set by a small current sensing resistor
± 2% output voltage accuracy in the CV mode
Cable wire resistance compensation.
Input and output over voltage protections (OVP)
Cycle-by-cycle switching peak current limit
Soft start for power-up
160oC over temperature shutdown
under-voltage lockout (UVLO)
Frequency dithering to reduce EMI
60mW no load power consumption
ESOP-8 and QFN16 （ 4* 4mm ） package
RoHS & HF(Halogen free) compliant
Step-down DC/DC conversion
Larger current battery charging adaptors