器件名称: DI-92
功能描述: 0.5 W Non-Isolated Constant Current LED Driver
文件大小: 539.19KB 共2页
简 介:Design Idea DI-92 LinkSwitch-TN 0.5 W Non-Isolated
Constant Current LED Driver
Application LED Driver Device LNK302P Power Output 0.5 W Input Voltage 85-265 VAC Output Current 40 mA Topology Buck-Boost
Design Highlights
Extremely low component count – only 9 components required Universal AC input range – single design worldwide Low cost, small size and very lightweight Replacement for passive capacitor or resistor droppers High efciency (approximately 70% at 85 VAC) Meets EN55022 B EMI limits with >8 dB margin (see Figure 2)
in this application, the device will switch and ramp up to the current limit for each and every cycle. Since the peak current is limited and xed for each cycle, the output power is solely determined by the size of the inductor. It is recommended that this design operate in the discontinuous conduction mode (DCM). Besides better EMI performance, this also ensures that a low cost 75 ns reverse recovery diode such as the UF4005 can be used. For designs that operate in the continuous conduction mode (CCM), a more expensive but faster diode (30 ns reverse recovery) like the BYV26C may be required. The output will be replenished every switching cycle (66 kHz), and thus the need for the output lter capacitor is eliminated. Persistence of vision of the human eye (typically 10 ms) is much longer than the switching period, and it thus sees a consistent light output without icker. Select the value of L1 following the LinkSwitch-TN Design Guide (www.powerint……
