Analog Devices LT8302 | Demoboard DC2014A

Description

Demonstration circuit 2014A is a micropower No-Optoisolated flyback converter featuring the LT®8302. This democircuit outputs 5V, and maintains tight regulation with aload current from 10mA to 2.2A over an input voltagefrom 10V to 30V. The output current capability increaseswith the input voltage.The LT8302 typically needs less than 0.5% of its full outputpower as a minimum load to maintain good output voltageregulation. On the DC2014A, in order to avoid pre-loading,a 5.6V Zener diode is placed between its VOUT+ and VOUT–to serve as a minimum load.Transformer leakage inductance causes a voltage spikeon the primary side after the power switch turns off. Tolimit this leakage inductance spike within MOSFET voltagerating of 65V, an RC snubber and a TVS clamp areinstalled to damp the ringing and clamp the MOSFET drainvoltage to a safe level.The Performance Summary table summarizes the performanceof the demo board at room temperature. The democircuit can be easily modified for different applications withsome pre-designed transformers.The LT®8302 is a simple to use monolithic micropowerisolated flyback converter. By sampling the isolated outputvoltage directly from the primary-side flyback waveform,the part requires no third winding or opto-isolator forregulation. The output voltage is programmed with twoexternal resistors and a third optional temperature compensationresistor. By integrating the loop compensation andsoft-start inside, the part reduces the number of externalcomponents. Boundary mode operation provides a smallmagnetic solution with excellent load regulation. Low rippleBurst Mode® operation maintains high efficiency at lightload while minimizing the output voltage ripple. A 3.6A,65V DMOS power switch is integrated along with all thehigh voltage circuitry and control logic into a thermallyenhanced 8-lead SO package.The LT8302 data sheet gives a complete description ofthe part, operation and application information. The datasheet must be read in conjunction with this quick startguide for demo circuit 2014A.

More information

• Datasheet
• IC product information