EVL90WADP-LLCSR STMicroelectronics, EVL90WADP-LLCSR Datasheet - Page 14

• Manufacturer Part Number: EVL90WADP-LLCSR
• Description: EVAL BOARD PORTABLE PWR SUPPLY
• Manufacturer: STMicroelectronics
• Type: Power Factor Correctionr

Specifications of EVL90WADP-LLCSR

• Main Purpose: AC/DC, Primary and Secondary Side with PFC
• Outputs And Type: 1, Isolated
• Power - Output: 90W
• Voltage - Output: 19V
• Current - Output: 4.75A
• Voltage - Input: 90 ~ 264VAC
• Regulator Topology: Boost
• Frequency - Switching: 130kHz
• Board Type: Fully Populated
• Utilized Ic / Part: L6563H, L6599A, SRK2000
• Input Voltage: 90 V to 264 V
• Output Voltage: 19 V
• Dimensions: 65 mm x 155 mm
• Product: Power Management Modules
• Supply Current: 4.75 A
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: L6563H, L6599A, SRK2000
• Other names: 497-10377

Functional check
14/28
Figure 12. Transition full load to no load at
Overcurrent and short-circuit protection
The L6599A is equipped with a current sensing input (pin 6, ISEN) and a dedicated
overcurrent management system. The current flowing in the resonant tank is detected and
the signal is fed to the ISEN pin. It is internally connected to a first comparator, referenced to
0.8 V, and to a second comparator referenced to 1.5 V. If the voltage externally applied to
the pin exceeds 0.8 V, the first comparator is tripped, causing an internal switch to be turned
on and discharging the soft-start capacitor CSS.
Under output short-circuit, this operation results in a nearly constant peak primary current.
With the L6599A, designers can externally program the maximum time that the converter is
allowed to run in overload or short-circuit conditions. Overloads or short-circuits lasting less
than the set time do not cause any protective action, thus providing the system with
immunity to short-duration phenomena. If, instead, an overload condition continues, a
protection procedure is activated that shuts down the L6599A and, in case of continuous
overload/short-circuit, results in continuous intermittent operation with a user-defined duty
cycle. This function is realized with the DELAY pin (pin 2) by means of a capacitor (C45) and
the parallel resistor R24 connected to ground. If the voltage on the ISEN pin exceeds 0.8 V,
the first OCP comparator, in addition to discharging CSS, turns on an internal 150 µA
current generator which, via the DELAY pin, charges C45. If the voltage on C45 is 3.5 V, the
L6599A stops switching and the PFC_STOP pin is pulled low. Also, the internal generator is
turned off, so that C45 is now slowly discharged by R24. The IC restarts when the voltage
on C45 is less than 0.3 V. Additionally, if the voltage on the ISEN pin reaches 1.5 V for any
reason (e.g. transformer saturation), the second comparator is triggered, the L6599A shuts
down, and operation resumes after an off-on cycle.
265 Vac - 50 Hz
Doc ID 16064 Rev 1
Figure 13. Transition no load to full load at
265 Vac - 50 Hz
AN3014