UC3525

The UC3525 is a regulating pulse width modulators.It pulse width modulator integrated circuits are de-signed to offer improved performance and lowered external parts count when used in designing all types of switching power supplies.It also feature built-in soft-start circuitry with only an external timing ca-pacitor required. These functions are also controlled by an undervoltage lockout which keeps the outputs off and the soft-start capacitor discharged for sub-normal input volt-ages.The UC3525A output stage features NOR logic, giving a LOW output for an OFF state.It utilizes OR logic which results in a HIGH output level when OFF.

Features of the UC3525 are:(1)8 to 35v operation;(2)5.1v reference trimmed to ±1%;(3)100hz to 500khz oscillator range;(4)separate oscillator sync terminal;(5)adjustable deadtime control;(6)internal soft-start;(7)pulse-by-pulse shutdown;(8)input undervoltage lockout with hysteresis;(9)latching pwm to prevent multiple pulses;(10)dual source/sink output drivers.

The absolute maximum ratings of the UC3525 can be summarized as:(1)Supply Voltage, (+V_IN):+40V;(2)Collector Supply Voltage (V_C):+40V;(3)Logic Inputs:0.3V to +5.5V;(4)Analog Inputs:0.3V to +V_IN;(5)Output Current, Source or Sink:500mA;(6)Reference Output Current:50mA;(7)Oscillator Charging Current:5mA;(8)Power Dissipation at T_A = +25°C (Note 2):1000mW;(9)Power Dissipation at T_C = +25°C (Note 2):2000mW;(10)Operating Junction Temperature:55°C to +150°C;(11)Storage Temperature Range:65°C to +150°C;(12)Lead Temperature (Soldering, 10 seconds):+300°C.Note 1: Values beyond which damage may occur.Note 2: Consult packaging Section of Databook for thermal limitations and considerations of package.

If you want to know more information such as the electrical characteristics about the UC3525, please download the datasheet in www.seekic.com or www.chinaicmart.com .