L6563ATR STMicroelectronics, L6563ATR Datasheet - Page 30

• Manufacturer Part Number: L6563ATR
• Description: IC PFC CTRLR TRANSITION 14SOIC
• Manufacturer: STMicroelectronics

Specifications of L6563ATR

• Mode: Discontinuous (Transition)
• Current - Startup: 50µA
• Voltage - Supply: 10.3 V ~ 22 V
• Operating Temperature: -25°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 14-SOIC (3.9mm Width), 14-SOL
• Maximum Operating Temperature: + 150 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 25 C
• For Use With: 497-9082 - EVAL BOARD L6563 (200W)497-8850 - BOARD EVAL FOR L6563/STW55NM60N497-8834 - BOARD DEMO FOR L6563/LL6566A497-8429 - BOARD ADAPTER L6599/STP12NM50N497-5854 - DEMO BOARD FOR L6563497-5496 - EVAL BOARD FOR L6599497-5493 - EVAL BOARD FOR L6563
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Frequency - Switching: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 497-6129-2

Application information
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Figure 44. Interface circuits that let the L6563/A switch on or off a PWM controller
If this is not the case or it is not possible to achieve a start-up delay long enough (because
this prevents the DC-DC stage from starting up correctly) or, simply, the PWM controller is
devoid of soft start, the arrangement of
the voltage generated by the PFC stage reaches a preset value. The technique relies on the
UVLO thresholds of the PWM controller.
Figure 45. Interface circuits for actual power-up sequencing (master PFC)
Another possible use of the RUN and PWM_STOP pins (again, in systems where the PFC
stage is the master) is brownout protection, thanks to the hysteresis provided.
Brownout protection is basically a not-latched device shutdown function that must be
activated when a condition of mains undervoltage is detected. This condition may cause
overheating of the primary power section due to an excess of RMS current. Brownout can
also cause the PFC pre-regulator to work open loop and this could be dangerous to the PFC
stage itself and the downstream converter, should the input voltage return abruptly to its
rated value. Another problem is the spurious restarts that may occur during converter power
down and that cause the output voltage of the converter not to decay to zero monotonically.
For these reasons it is usually preferable to shutdown the unit in case of brownout.
Figure 45
lets the DC-DC converter start-up when
L6563 - L6563A