データシートサーチシステム
  Japanese  ▼
ALLDATASHEET.JP

X  

Preview PDF HTML

PM6670 データシート(PDF) 21 Page - STMicroelectronics

部品番号 PM6670
部品情報  Complete DDR2/3 memory power supply controller
PDF  53 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
メーカー  STMICROELECTRONICS [STMicroelectronics]
ホームページ  http://www.st.com
Logo STMICROELECTRONICS - STMicroelectronics

PM6670 データシート(HTML) 21 Page - STMicroelectronics

Back Button PM6670 Datasheet HTML 17Page - STMicroelectronics PM6670 Datasheet HTML 18Page - STMicroelectronics PM6670 Datasheet HTML 19Page - STMicroelectronics PM6670 Datasheet HTML 20Page - STMicroelectronics PM6670 Datasheet HTML 21Page - STMicroelectronics PM6670 Datasheet HTML 22Page - STMicroelectronics PM6670 Datasheet HTML 23Page - STMicroelectronics PM6670 Datasheet HTML 24Page - STMicroelectronics PM6670 Datasheet HTML 25Page - STMicroelectronics Next Button
Zoom Inzoom in Zoom Outzoom out
 21 / 53 page
background image
PM6670
Device description
21/53
The duty-cycle of the buck converter is, in steady-state conditions, given by
Equation 2
The switching frequency is thus calculated as
Equation 3
where
Equation 4a
Equation 4b
Referring to the typical application schematic (figures on cover page and Figure 29), the
final expression is then:
Equation 5
Even if the switching frequency is theoretically independent from battery and output
voltages, parasitic parameters involved in power path (like MOSFETs' on-resistance and
inductor's DCR) introduce voltage drops responsible for slight dependence on load current.
In addition, the internal delay is due to a small dependence on input voltage. The PM6670
switching frequency can be set by an external divider connected to the VOSC pin.
Figure 29. Switching frequency selection and VOSC pin
The voltage seen at this pin must be greater than 0.8V and lower than 2V in order to ensure
the system's linearity.
D
V
OUT
V
IN
--------------
=
OSC
OUT
OSC
OSC
SNS
OSC
IN
OUT
ON
SW
K
1
V
V
K
V
V
T
D
f
⋅
α
α
=
=
=
α
OSC
V
OSC
V
IN
---------------
=
α
OUT
V
SNS
V
OUT
--------------
=
OSC
2
1
2
OSC
OSC
SW
K
1
R
R
R
K
f
⋅
+
=
α
=
PM6670
VOSC
R1
R2
VIN



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 52 53


データシート ダウンロード

Go To PDF Page


リンク URL



ALLDATASHEETはお客様のビジネスに役立ちますか？  [ DONATE ] 

Alldatasheetは   |   広告   |   お問い合わせ   |   プライバシーポリシー   |   データシートへのリンク    |   リンク交換   |   メーカーリスト
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