VIPER17LD STMicroelectronics, VIPER17LD Datasheet - Page 22

• Manufacturer Part Number: VIPER17LD
• Description: IC OFFLINE CONV PWM OVP 16SOIC
• Manufacturer: STMicroelectronics
• Series: VIPer™ plusr

Specifications of VIPER17LD

• Output Isolation: Isolated
• Frequency Range: 54 ~ 66kHz
• Voltage - Input: 8.5 ~ 23.5 V
• Voltage - Output: 800V
• Power (watts): 12W
• Operating Temperature: -40°C ~ 150°C
• Package / Case: 16-SOIC (0.154", 3.90mm Width) Exposed Pad
• Output Voltage: 800 V
• Output Power: 1 W
• Input Voltage: - 0.3 V
• Switching Frequency: 115 KHz
• Operating Temperature Range: - 40 C to + 150 C
• Mounting Style: SMD/SMT
• Duty Cycle (max): 80 %
• Number Of Outputs: 1
• For Use With: 497-9052 - BOARD EVAL FOR VIPER17LN497-9050 - BOARD DEMO BASED ON VIPER17HN497-9007 - BOARD EVAL BASED ON VIPER17497-8513 - BOARD EVAL VIPER17HN 6W SMPS
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Operation descriptions
22/31
Equation 7
Equation 8
The R
The C
The
considered instead of C
satisfy, in all case, the loop stability and the enough OLP delay time alike.
Figure 28. FB pin configuration
Figure 29. FB pin configuration
Equation 5
FB(DYN)
FB1
capacitor fixes the OLP delay and usually C
is the dynamic resistance seen by the FB pin.
can be still used to calculate the OLP delay time but C
Rfb1
Cfb1
FB
. Using the alternative compensation network, the designer can
Cfb
f
f
PFB
PFB
Cfb
Doc ID 14419 Rev 7
1
=
=
2
2
⋅
⋅
⋅ π
⋅ π
CONTROL
R
C
C
PWM
FB
FB
FB
CONTROL
PWM
BURST-MODE
1
(
DYN
References
⋅
⋅
(
(
R
R
1
FB
)
FB
References
+
V FBolp
1
(
DYN
R
+
V FBolp
FB
R
FB1
)
FB
OLP comparator
1
⋅
R
(
DYN
results much higher than C
BURST-MODE
PWM
OLP comparator
FB
From sense FET
+
+
-
-
LOGIC
1
)
BURST-MODE
)
)
PWM
From R
+
+
-
-
LOGIC
SENSE
To disable logic
To PWM Logic
To disable logic
FB1
BURST
To GATE driver
BURST
has to be
VIPER17
FB
.