UC2840

The UC2840 is designed as one kind of current mode PWM controller that belongs to the UC2842 family. This device has the UVLO threshold of 16V (on) and 10V (off), this UVLO threshold can be used in off-line applications, and could operates to duty cycles approaching 100%.

Features of the UC2840 are:(1)optimized for off-line and DC to DC converters; (2)low start up current (<1mA); (3)automatic feed forward compensation; (4)pulse-by-pulse current limiting; (5)enhanced load response characteristics; (6)under-voltage lockout with hysteresis; (7)double pulse suppression; (8)high current totem pole output; (9)internally trimmed bandgap reference; (10)500khz operation; (11)low RO error amp.

The absolute maximum ratings of the UC2840 can be summarized as:(1)Supply Voltage (Low Impedance Source): 32 V;(2)Supply Voltage (ICC <30mA): Self Limiting;(3)Output Current: 400 mA;(4)Output Energy (Capacitive Load): 20 uJ;(5)Analog Inputs (Pins 2, 3): -0.3 V to +6.3 V;(6)Error Amp Output Sink Current: 10 mA;(7)Power Dissipation at TA </= 25°C (DIL-8): 1 W;(8)Power Dissipation at TA </= 25°C (SOIC-14): 725 mW;(9)Storage Temperature Range: -65°C to +150°C;(10)Lead Temperature (Soldering, 10 Seconds): 300°C.

The electrical characteristics of this device UC2840 can be summarized as:(1)Output Voltage: 4.95 V to 5.05 V;(2)Line Regulation: 6 mV to 20 mV;(3)Load Regulation: 6 to 25 mV;(4)Total Output Variation: 4.9 to 5.1 V;(5)Output Noise Voltage: 50 uV;(6)Long Term Stability: 5 to 25 mV;(7)Output Short Circuit: -30 to -180 mA;(8)Delay to Output: 150 ns to 300 ns;(9)Input Bias Current: -2 to -10 uA;(10)PSRR: 70 dB. If you want to know more information such as the electrical characteristics about it, please download the datasheet in www.seekic.com or www.chinaicmart.com.