RM6203 datasheet(5/7 Pages) REACTOR

5 / 7 page

RM6203

www.reactor-micro.com

open current will increase along with IS linearly, when IS raises

to 0.6V, the OB open current is approximately 100mA, this

feature will effectively utilize the output current of OB and lower

the power consumption of RM6203), if IS detects the specified

current of FB, it goes into close period; in the close period, OB

pulls down, the power tube may not be turned off immediately,

but OE clamps on 2.0V (after the power tube turns off, the

base will be reverse bias and the voltage withstanding

capacity is increased); in the open or close period, if it detects

the current exceeding upper limit of the power tube, then the

upper limit flip-flop will be put at the preferential position,

forcing FB to decrease and the duty ratio will turn smaller, so

that the power tube and transformer will be protected; at the

beginning of next close period edge or if FB is below 1.8V, the

upper limit flip-flop will reset. Besides, the built-in heat

protection of RM6203 will widen the oscillator period when the

internal temperature is above 125 ℃ to ensure the

temperature of RM6203 will not exceed 135℃; the built-in

slope compensation will stabilize the open/close period when

RM6203 is at high duty ratio or in continuous current mode.

When VCC lowers to about 4.4V, the oscillator will be

closed, OSC1 and OSC2 will be at low level, and the power

source will be maintained at close period; when VCC goes on

lowering to about 3.8V, RM6203 will enter the enabling stage

again.

Normal Stage Switching Cycle Oscillogram

Global Oscillogram

RM6203 Datasheet(PDF) 5 Page - Shaanxi Reactor Microelectronics Co., Ltd.