STMicroelectronics UC3843AN Current Mode PWM Controller 1A 8-Pin PDIP

Description

STMicroelectronics SGS UC3843AN ADVANCED PWM CONTROLLER 3843 DIP8; Controller Type:PWM; Voltage Input Max:25V; Current Output Max:4A; Output Type:Totem Pole; Current Input:11mA; Energy Output per Cycle:55J; Frequency:500kHz; Power Dissipation:1W

Description

• Pulse Width Modulation (PWM) Controller IC
• Input Voltage:25V
• Output Voltage:15V
• Output Current:1A
• Frequency:450kHz
• Supply Voltage Range:12V to 25V
• Digital IC Case Style:DIP
• No. of Pins:8
• RoHS Compliant: Yes

The UC1842/3/4/5 family of control ICs provides the necessary features to im- plement off-line or DC to DC fixed frequency current mode control schemes with a minimal external parts count. Internally implemented circuits include un- der-voltage lockout featuring start up current less than 1mA, a precision refer- ence trimmed for accuracy at the error amp input, logic to insure latched operation, a PWM comparator which also provides current limit control, and a totem pole output stage designed to source or sink high peak current. The out- put stage, suitable for driving N Channel MOSFETs, is low in the off state.

Differences between members of this family are the under-voltage lockout
thresholds and maximum duty cycle ranges. The UC1842 and UC1844 have
UVLO thresholds of 16V (on) and 10V (off), ideally suited to off-line applica-
tions. The corresponding thresholds for the UC1843 and UC1845 are 8.4V
and 7.6V. The UC1842 and UC1843 can operate to duty cycles approaching
100%. A range of zero to 50% is obtained by the UC1844 and UC1845 by the
addition of an internal toggle flip flop which blanks the output off every other
clock cycle.

Manufacturer Part Number: UC3843AN

Manufacturer: STMicroelectronics

Datasheet: Motorola/uc2842ad_92eea4df92.pdf