数据搜索系统，热门电子元器件搜索
  Chinese  ▼
ALLDATASHEETCN.COM

X  

预览 PDF HTML

L6566B 数据表(PDF) 23 Page - STMicroelectronics

部件名 L6566B
功能描述  Multi-mode controller for SMPS
PDF  51 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
制造商  STMICROELECTRONICS [STMicroelectronics]
网页  http://www.st.com
标志 STMICROELECTRONICS - STMicroelectronics

L6566B 数据表(HTML) 23 Page - STMicroelectronics

Back Button L6566B Datasheet HTML 19Page - STMicroelectronics L6566B Datasheet HTML 20Page - STMicroelectronics L6566B Datasheet HTML 21Page - STMicroelectronics L6566B Datasheet HTML 22Page - STMicroelectronics L6566B Datasheet HTML 23Page - STMicroelectronics L6566B Datasheet HTML 24Page - STMicroelectronics L6566B Datasheet HTML 25Page - STMicroelectronics L6566B Datasheet HTML 26Page - STMicroelectronics L6566B Datasheet HTML 27Page - STMicroelectronics Next Button
Zoom Inzoom in Zoom Outzoom out
 23 / 51 page
background image
L6566B
Application information
23/51
start-up, at the end of the soft-start phase the output voltage of the converter must meet the
condition:
Equation 4
where Ns is the turn number of the secondary winding, Naux the turn number of the
auxiliary winding and IZCD the maximum pull-up current (130 µA).
The operation described so far under different operating conditions for the converter is
illustrated in the timing diagrams of Figure 10.
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 Section 5.11: OVP block on page 35 ).
ZCD
1
Z I
R
Naux
Ns
Vout
>
Figure 10.
Operation of ZCD, triggering and oscillator blocks (QR option active)
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


数据表 下载

Go To PDF Page


链接网址



ALLDATASHEET是否为您带来帮助?  [ DONATE ] 

关于 Alldatasheet   |   广告服务   |   联系我们   |   隐私政策   |   数据表链接    |   链接交换   |   制造商名单
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