KA3842 Current-Mode PWM Controller IC DIP-8

Description

KA3842 Current-Mode PWM Controller IC DIP-8 The KA3842 is a high-performance current-mode PWM controller IC designed for off-line and DC-DC converter applications that require high efficiency, precision control, and fast response. It operates as a fixed-frequency controller and provides all the essential functions needed for implementing reliable and cost-effective switch-mode power supplies (SMPS). With a wide operating voltage range of 7.6 V to 30 V and a precision 5.0 V reference, the KA3842 delivers stable operation across a variety of input conditions. Featuring a high-speed totem-pole output, the KA3842 can directly drive power MOSFETs or BJTs with peak currents up to 1 A, ensuring efficient switching and reduced power losses. Its current-mode control architecture provides superior line and load regulation, automatic pulse-by-pulse current limiting, and inherent cycle-by-cycle overcurrent protection. The KA3842 includes undervoltage lockout (UVLO) with typical start and stop thresholds of 16 V and 10 V, making it particularly well suited for off-line (AC-to-DC) power supplies and continuous conduction mode designs. Housed in a compact DIP-8 package, it offers a cost-effective solution for applications such as industrial power supplies, motor drivers, and battery chargers that demand robust, efficient PWM control. Features Wide Operating Voltage Range: 7.6 V to 30 V. Precision 5.0 V Reference: ±2% tolerance for accurate regulation. Fixed-Frequency Operation: Up to 500 kHz (set by external RT/CT). Current-Mode Control: Provides superior line and load regulation with cycle-by-cycle current limiting. High-Speed Totem-Pole Output: ±1 A peak drive capability for direct MOSFET or transistor control. Low Start-Up Current: Less than 0.5 mA for high-efficiency standby operation. Undervoltage Lockout (UVLO): Start-up at 16 V, turn-off at 10 V for off-line power applications. Built-In Soft-Start and Leading-Edge Blanking: Enhances system stability and noise immunity. Thermal Stability: Ensures consistent performance over temperature range. Standard 8-Pin DIP/SOP Package: Simplifies design integration and PCB layout. Pinout Configuration Pin No. Symbol Name / Function 1 COMP Compensation input – error amplifier output used for loop compensation 2 VFB Feedback input – voltage feedback to the internal error amplifier 3 ISENSE Current sense input – monitors switch current for current-mode control and protection 4 RT/CT Oscillator timing resistor/capacitor – sets the switching frequency 5 GND Ground reference for all signals 6 OUTPUT Output drive pin – to drive an external MOSFET or transistor 7 VCC Supply voltage input (operating range: 7.6 V – 30 V) 8 VREF 5 V reference output (can source up to 20 mA for biasing) Dimensions Specifications Parameter Descriptions Product Type Current-Mode PWM Control IC Part Number KA3842A Datasheet KA3842 Package Type DIP-8 Operating Voltage Range 7.6 V – 30 V Reference Voltage 5.0 V ±2% Oscillation Frequency 500 kHz Output Type Adjustable Topology Supported Buck, Boost, Flyback, Forward Number of Channels 1 Switch Type External MOSFET required Undervoltage Lockout (UVLO) 16V (start) – 10V (stop) Output Drive Capability ±1 A peak Optimization General-purpose PWM control, suitable for wide duty cycle designs Maximum Duty Cycle 100% UVLO Thresholds (Start/Stop) Slightly higher thresholds Design Flexibility Allows full-range duty cycles for continuous conduction designs Control Method Fixed-frequency peak current-mode PWM Main Application Off-line SMPS / AC-DC converter, High-Voltage Converters, Continuous Flyback Operating Temperature Range 0 °C – +70 °C Applications Switch-Mode Power Supplies (SMPS). DC-DC Converter Circuits. Battery Chargers and Power Adapters. LED Drivers and Lighting Power Supplies. Motor Speed Control Systems. Inverter and Converter Modules. Industrial and Consumer Power Electronics. Offline Flyback and Forward Converter Designs. Package Contents 1 x KA3842 Current-Mode PWM Controller IC DIP-8 Datasheet KA3842

From the supplier's page.