EVL6563S-400W STMicroelectronics, EVL6563S-400W Datasheet - Page 19

• Manufacturer Part Number: EVL6563S-400W
• Description: EVAL BOARD FOR L6563(400W)
• Manufacturer: STMicroelectronics
• Type: Motor / Motion Controllers & Driversr

Specifications of EVL6563S-400W

• Main Purpose: Power Management, Power Factor Correction
• Embedded: No
• Utilized Ic / Part: L6563
• Primary Attributes: 400W Power Factor Correction and Preregulator Combination
• Secondary Attributes: Transition Mode & Active Tracking Boost Function.
• Maximum Operating Temperature: + 60 C
• Product: Power Management Development Tools
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: L6563S
• Other names: 497-10488

AN2994
2.5
Brownout function
A dangerous event for any PFC is the operation during a mains undervoltage. This condition
may cause overheating of the power section due to an excess of RMS current. To protect
the PFC from this abnormal operation, a brownout protection is needed. It is basically a non-
latched shutdown function that has to be activated when a mains undervoltage condition is
detected.
The L6563S has a dedicated inhibit pin (RUN, #10) that embeds a comparator with
hysteresis and which stops the L6563S operation if the voltage applied is below its
threshold. Because the L6563S V
mains, the complete brownout function can be easily realized using a simple resistor divider
connected between the V
setting the turn-on threshold are R26 and R27 on the schematic in
shows a start-up tentative below the threshold. As visible at start-up, the RUN pin does not
allow the PFC start-up.
Figure 30
protection. In both cases, the mains voltages were increased or decreased slowly. As you
can see, at both turn-on and turn-off, there are no bouncing or starting attempts by the
converter.
Figure 29. EVL6563S-400W start-up attempt at 80 Vac, 60 Hz, full load
CH1: Output voltage
CH2: Pin #14 - Vcc voltage
CH3: Pin #10 - RUN
CH4: Pin #13 - Gate drive
and
Figure 31
show the waveforms of the circuit during operation of the brownout
FF
and RUN pins. In this demonstration board, the divider resistors
Doc ID 15796 Rev 2
FF
pin delivers a voltage signal proportional to the input
Test results and significant waveforms
Figure
1.
Figure 29
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