EVL170W-FTV STMicroelectronics, EVL170W-FTV Datasheet - Page 27

• Manufacturer Part Number: EVL170W-FTV
• Description: DEMO BOARD VIPER27 L6599A L6564
• Manufacturer: STMicroelectronics
• Series: VIPER™r

Specifications of EVL170W-FTV

• Main Purpose: Power Supply with PFC
• Outputs And Type: 2, Isolated
• Power - Output: 170W
• Voltage - Output: 24V, 12V, 5V
• Current - Output: 6A, 2A, 2A
• Voltage - Input: 90 ~ 264VAC
• Regulator Topology: Flyback
• Frequency - Switching: 130kHz
• Board Type: Fully Populated
• Utilized Ic / Part: Viper27LN, L6564, L6599A
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 497-11254

AN3329
Figure 52. Startup by on/off signal at full load
Figure 54. OVP at full load and 115 Vac - 60 Hz
CH1: On/off signal
CH1: HB voltage
CH3: 24 V output
CH3: V_C53
Overvoltage protection
Figure 54
loop. Upon an overvoltage condition of either 24 V or 12 V output, the Zener diodes D16 and
D17 are reverse-biased and conduct respectively, forcing Q10 on by the resulting base
current, which causes Q9 to conduct shorting to ground the anode of the U5 optocoupler
and the disappearance of V_C44. Therefore, the L6564 and the L6599A are not powered.
The two transistors mentioned form a pnp-npn SCR structure that force the PFC and
resonant converter to be latched off until the 5 V standby is removed by a mains voltage
recycling. In the case of an open loop event, the 12 V and 24 V outputs reach 14.16 V and
28.26 V respectively.
and 115 Vac - 60 Hz O/P voltage
rising
on 12 V - 24 V
and
CH2: CSS (pin #1)
CH4: 12 V output
CH2: PFC drain
CH4: V_C44
55
show the OVP response, observed opening the resonant stage feedback
Doc ID 18376 Rev 1
Figure 53. Turn-off at full load and 115 Vac - 60
Figure 55. OVP at full load and 115 Vac - 60 Hz
CH1: HB voltage
CH1: 24 V output
CH3: V_C44
CH3: V_C53
Hz by on/off signal
on 12 V - 24 V - outputs detail
CH2: PFC drain
CH4: On/off signal
CH2: 12 V output
CH4: V_C44
Functional check
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