Motore di ricerca datesheet componenti elettronici
  Italian  ▼
ALLDATASHEETIT.COM

X  

Preview PDF HTML

PM6670STR Scheda tecnica(PDF) 21 Page - STMicroelectronics

Il numero della parte PM6670STR
Spiegazioni elettronici  Complete DDR2/3 memory power supply controller
PDF  53 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Produttore elettronici  STMICROELECTRONICS [STMicroelectronics]
Homepage  http://www.st.com
Logo STMICROELECTRONICS - STMicroelectronics

PM6670STR Scheda tecnica(HTML) 21 Page - STMicroelectronics

Back Button PM6670STR Datasheet HTML 17Page - STMicroelectronics PM6670STR Datasheet HTML 18Page - STMicroelectronics PM6670STR Datasheet HTML 19Page - STMicroelectronics PM6670STR Datasheet HTML 20Page - STMicroelectronics PM6670STR Datasheet HTML 21Page - STMicroelectronics PM6670STR Datasheet HTML 22Page - STMicroelectronics PM6670STR Datasheet HTML 23Page - STMicroelectronics PM6670STR Datasheet HTML 24Page - STMicroelectronics PM6670STR Datasheet HTML 25Page - STMicroelectronics Next Button
Zoom Inzoom in Zoom Outzoom out
 21 / 53 page
background image
PM6670S
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 PM6670S
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 0.8 V and lower than 2 V 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
PM6670S



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


Scheda tecnica Scarica

Go To PDF Page


Link URL



Lei ha avuto il aiuto da alldatasheet?  [ DONATE ] 

Di alldatasheet   |   Richest di pubblicita   |   contatti   |   Privacy Policy   |   Collegamento alla scheda tecnica    |   scambio Link   |   Ricerca produttore
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