DESCRIPTIONThe UC384xB family of control ICs provides the necessary features to implement off-line or DC to DC fixed frequency current mode control schemes with a minimal external parts count. Internally implemented circuits include a trimmed oscillator for precise DUTY CYCLE CONTROL under voltage lockout featuring start-up current less than 0.5mA, a precision reference 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 output stage, suitable for driving N-Channel MOSFETs, is low in the offstate.

■ TRIMMED OSCILLATOR FOR PRECISE FREQUENCY CONTROL
■ OSCILLATOR FREQUENCY GUARANTEED AT 250kHz
■ CURRENT MODE OPERATION TO 500kHz
■ AUTOMATIC FEED FORWARD COMPENSATION
■ LATCHING PWM FOR CYCLE-BY-CYCLE CURRENT LIMITING
■ INTERNALLY TRIMMED REFERENCE WITH UNDERVOLTAGE LOCKOUT
■ HIGH CURRENT TOTEM POLE OUTPUT
■ UNDERVOLTAGE LOCKOUT WITH HYSTERESIS
■ LOW START-UP AND OPERATING CURRENT

Manufacturer	STMicroelectronics
Product Category	AC DC Converters, Offline Switchers
Series	-
Packaging	Tube
Package-Case	8-DIP (0.300", 7.62mm)
Operating-Temperature	-40°C ~ 150°C (TJ)
Mounting-Type	Through Hole
Supplier-Device-Package	8-Mini DIP
Watt	-
Output-Isolation	Isolated
Internal-Switch-s	No
Voltage-Breakdown	-
Topology	Forward
Voltage-Start-Up	16V
Voltage-Supply-Vcc-Vdd	10 V ~ 30 V
Duty-Cycle	48%
Frequency-Switching	Up to 500kHz
Fault-Protection	Current Limiting
Control-Features	Frequency Control