STEVAL-ILL027V1 STMicroelectronics, STEVAL-ILL027V1 Datasheet - Page 5

• Manufacturer Part Number: STEVAL-ILL027V1
• Description: BOARD EVAL LED DRIVER FOR L6562A
• Manufacturer: STMicroelectronics

Specifications of STEVAL-ILL027V1

• Design Resources: STEVAL-ILL027V1 Schematics STEVAL-ILL027V1 BOM STEVAL-ILL027V1 Gerber Files
• Current - Output / Channel: 260mA
• Outputs And Type: 1, Non-Isolated
• Voltage - Output: 70V
• Features: Short-Circuit Protection
• Voltage - Input: 120VAC
• Utilized Ic / Part: L6562A
• Product: Display Modules
• Lead Free Status / RoHS Status: Lead free by exemption / RoHS compliant by exemption
• Other names: 497-10170

AN3111
1
Circuit design
The L6562A is a current mode PFC controller operating in transition mode (boundary mode
between CCM and DCM). Its linear multiplier enables the converter to shape the AC input
current waveform following the input voltage. The block diagram of the L6562A is shown in
Figure 2
device datasheet and application notes.
Figure 2.
Figure 3
current is constant, the power of the converter is constant. As the LED string is
a constant voltage load, we can obtain a constant current in the LED string. This makes it
possible to leave out the LED current sensing, therefore simplifying the circuit design. If the
inductor current is constant, then the power factor of the circuit is very poor. The input
current waveform is greatly distorted during line voltage zero crossing. If there is a way to
reduce the current amplitude near the line voltage zero crossing, the power factor can be
improved. The L6562A PFC controller is used to achieve this objective. The idea is to
reduce the current amplitude near the line voltage zero crossing, which results in an
improved power factor.
below. For more detailed information regarding the L6562A, please refer to the
shows the schematic of the proposed single-stage LED driver. If the inductor
Block diagram for the L6562A
Doc ID 16815 Rev 2
Circuit design
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