L6566ATR STMicroelectronics, L6566ATR Datasheet - Page 23

• Manufacturer Part Number: L6566ATR
• Description: IC CTRLR OVP UVLO 16SOIC
• Manufacturer: STMicroelectronics

Specifications of L6566ATR

• Output Isolation: Isolated
• Frequency Range: 93 ~ 107kHz
• Voltage - Input: 8 ~ 23 V
• Power (watts): 750mW
• Operating Temperature: -40°C ~ 150°C
• Package / Case: 16-SOIC (0.154", 3.90mm Width)
• For Use With: 497-8834 - BOARD DEMO FOR L6563/LL6566A497-6452 - BOARD EVAL FOR L6566B497-6451 - BOARD EVAL FOR L6566B497-6450 - BOARD EVAL FOR L6566B497-6449 - BOARD EVAL FOR L6566A
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-6296-2

L6566A
Figure 10. Operation of ZCD, triggering and oscillator blocks (QR option active)
Arm/Trigger
PWM latch
PWM latch
ON-enable
Oscillator
Reset
blanking
(pin 11)
ramp
Set
(pin 4)
ZCD
time
ZCD
100 mV
GD
50 mV
armed
The operation described so far under different operating conditions for the converter is
illustrated in the timing diagrams of
If the FF option is selected the operation will be exactly equal to that of a standard current-
mode PWM controller. It will work at a frequency fsw = fosc; both DCM and CCM
transformer's operation are possible, depending on the operating conditions (input voltage
and output load) and on the design of the power stage. The MOSFET is turned on at the
beginning of each oscillator cycle and is turned off as the voltage on the current sense pin
reaches an internal reference set by the Line Feedforward block. The maximum duty cycle is
limited at 70 % minimum. The signal on the ZCD pin in this case is used only for detecting
feedback loop failures (see
trigger
a) full load
Arm/Trigger
ON-enable
PWM latch
PWM latch
Oscillator
Reset
blanking
(pin 11)
Set
ramp
(pin 4)
ZCD
ZCD
time
100 mV
GD
50 mV
Section 5.11: OVP block on page 35
Figure 10
b) light load
.
Arm/Trigger
ON-enable
PWM latch
PWM latch
Oscillator
Reset
blanking
(pin 11)
ramp
Set
(pin 4)
ZCD
ZCD
time
100 mV
GD
50 mV
).
Application information
c) start-up
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