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

X  

PM6680ATR 数据表(PDF) 19 Page - STMicroelectronics

部件名 PM6680ATR
功能描述  Dual synchronous step-down controller with adjustable output voltages plus LDO
PDF  48 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
制造商  STMICROELECTRONICS [STMicroelectronics]
网页  http://www.st.com
标志 STMICROELECTRONICS - STMicroelectronics

PM6680ATR 数据表(HTML) 19 Page - STMicroelectronics

Back Button PM6680ATR Datasheet HTML 15Page - STMicroelectronics PM6680ATR Datasheet HTML 16Page - STMicroelectronics PM6680ATR Datasheet HTML 17Page - STMicroelectronics PM6680ATR Datasheet HTML 18Page - STMicroelectronics PM6680ATR Datasheet HTML 19Page - STMicroelectronics PM6680ATR Datasheet HTML 20Page - STMicroelectronics PM6680ATR Datasheet HTML 21Page - STMicroelectronics PM6680ATR Datasheet HTML 22Page - STMicroelectronics PM6680ATR Datasheet HTML 23Page - STMicroelectronics Next Button
Zoom Inzoom in Zoom Outzoom out
 19 / 48 page
background image
PM6680A
Device description
19/48
Figure 28.
Constant ON time PWM control
The duty cycle of the buck converter in steady state is:
Equation 2
The PWM control works at a nearly fixed frequency fSW:
Equation 3
As mentioned the steady state switching frequency is theoretically independent from input
voltage and from output voltage.
Actually the frequency depends on parasitic voltage drops that are present during the
charging path(high side switch resistance, inductor resistance(DCR)) and discharging
path(low side switch resistance, DCR).
As a result the switching frequency increases as a function of the load current.
Standard switching frequency values can be selected for both sections by pin FSEL as
shown in the following table:
Table 6.
FSEL pin selection: typical switching frequency
Fsw@OUT1 = 3.3 V (kHz)
Fsw@OUT2 = 1.8 V (kHz)
FSEL = GND
195
335
FSEL = VREF
295
440
FSEL = LDO5
390
600
D
V
OUT
V
IN
--------------
=
f
SW
V
OUT
V
IN
--------------
K
on
V
OUT
V
IN
--------------
×
-------------------------------
1K
⁄
on
=
=



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


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