Electronic Components Datasheet Search
  English  ▼

X  

Preview PDF HTML

SO16N Datasheet(PDF) 22 Page - STMicroelectronics

Part # SO16N
Description  Multimode controller for SMPS
PDF  51 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  STMICROELECTRONICS [STMicroelectronics]
Direct Link  http://www.st.com
Logo STMICROELECTRONICS - STMicroelectronics

SO16N Datasheet(HTML) 22 Page - STMicroelectronics

Back Button SO16N Datasheet HTML 18Page - STMicroelectronics SO16N Datasheet HTML 19Page - STMicroelectronics SO16N Datasheet HTML 20Page - STMicroelectronics SO16N Datasheet HTML 21Page - STMicroelectronics SO16N Datasheet HTML 22Page - STMicroelectronics SO16N Datasheet HTML 23Page - STMicroelectronics SO16N Datasheet HTML 24Page - STMicroelectronics SO16N Datasheet HTML 25Page - STMicroelectronics SO16N Datasheet HTML 26Page - STMicroelectronics Next Button
Zoom Inzoom in Zoom Outzoom out
 22 / 51 page
background image
Application information
L6566BH
22/51
Doc ID 16610 Rev 2
5.3
Burst-mode operation at no load or very light load
When the voltage at the COMP pin (9) falls 20 mV below a threshold fixed internally at a
value, VCOMPBM, depending on the selected operating mode, the L6566BH is disabled with
the MOSFET kept in OFF-state and its consumption reduced to a lower value to minimize
VCC capacitor discharge.
The control voltage now increases as a result of the feedback reaction to the energy delivery
stop (the output voltage is slowly decaying), the threshold is exceeded and the device
restarts switching again. In this way the converter works in burst-mode with a nearly
constant peak current defined by the internal disable level. A load decrease then causes a
frequency reduction, which can go down even to few hundred hertz, therefore minimizing all
frequency-related losses and making it easier to comply with energy saving regulations.
This kind of operation, shown in the timing diagrams of
Figure 11 along with the others
previously described, is noise-free since the peak current is low.
If it is necessary to decrease the intervention threshold of the burst-mode operation, this can
be done by adding a small DC offset on the current sense pin as shown in
Figure 12.
Note:
The offset reduces the available dynamics of the current signal; thereby, the value of the
sense resistor must be determined taking this offset into account.
Figure 10.
Operation of ZCD, triggering and oscillator blocks (QR option active)
AM11486v1
a) full load
GD
(pin 4)
ZCD
blanking
time
ZCD
(pin 11)
Oscillator
ramp
PWM latch
Set
PWM latch
Reset
ON-enable
Arm/Trigger
50 mV
100 mV
armed
trigger
b) light load
ZCD
blanking
time
PWM latch
Set
PWM latch
Reset
ON-enable
Arm/Trigger
50 mV
100 mV
Oscillator
ramp
GD
(pin 4)
ZCD
(pin 11)
c) start-up
ZCD
blanking
time
PWM latch
Set
PWM latch
Reset
ON-enable
Arm/Trigger
50 mV
100 mV
Oscillator
ramp
GD
(pin 4)
ZCD
(pin 11)



Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51


Datasheet Download

Go To PDF Page


Link URL



Does ALLDATASHEET help your business so far?  [ DONATE ] 

About Alldatasheet   |   Advertisement   |   Contact us   |   Privacy Policy   |   Link to Datasheet    |   Link Exchange   |   Manufacturer List
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com