Electronic Components Datasheet Search
  New Zealand  ▼
ALLDATASHEET.CO.NZ

X  

Preview PDF HTML

PM6680ATR Datasheet(PDF) 34 Page - STMicroelectronics

Part # PM6680ATR
Description  Dual synchronous step-down controller with adjustable output voltages plus LDO
PDF  48 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  STMICROELECTRONICS [STMicroelectronics]
Direct Link  http://www.st.com
Logo STMICROELECTRONICS - STMicroelectronics

PM6680ATR Datasheet(HTML) 34 Page - STMicroelectronics

Back Button PM6680ATR Datasheet HTML 30Page - STMicroelectronics PM6680ATR Datasheet HTML 31Page - STMicroelectronics PM6680ATR Datasheet HTML 32Page - STMicroelectronics PM6680ATR Datasheet HTML 33Page - STMicroelectronics PM6680ATR Datasheet HTML 34Page - STMicroelectronics PM6680ATR Datasheet HTML 35Page - STMicroelectronics PM6680ATR Datasheet HTML 36Page - STMicroelectronics PM6680ATR Datasheet HTML 37Page - STMicroelectronics PM6680ATR Datasheet HTML 38Page - STMicroelectronics Next Button
Zoom Inzoom in Zoom Outzoom out
 34 / 48 page
background image
Design guidelines
PM6680A
34/48
Equation 22
Choose a synchronous rectifier with low RDSon. When high side MOSFET turns on, the fast
variation of the phase node voltage can bring up even the low side gate through its gate-
drain capacitance CRSS, causing cross-conduction problems. Choose a low side MOSFET
that minimizes the ratio CRSS/CGS (CGS = CISS - CRSS).
Below there is a list of some possible low side MOSFETs.
Dual n-channel MOSFETs can be used in applications with a maximum output current of
about 3 A. Below there is a list of some MOSFET manufacturers.
A rectifier across the low side MOSFET is recommended. The rectifier works as a voltage
clamp across the synchronous rectifier and reduces the negative inductor swing during the
dead time between turning the high-side MOSFET off and the synchronous rectifier on. It
can increase the efficiency of the switching section, since it reduces the low side switch
losses. A shottky diode is suitable for its low forward voltage drop (0.3 V). The diode reverse
voltage must be greater than the maximum input voltage VINmax. A minimum recovery
reverse charge is preferable. Below there is a list of some shottky diode manufacturers.
Table 10. Low side MOSFET manufacturer
Manufacturer
Type
RDSon (mΩ)
Rated reverse voltage
(V)
ST
STS7NF60L
[VC11] 19
0.0625
60
Table 14.
Dual MOSFET manufacturer
Manufacturer
Type
RDSon (mΩ)
Gate charge
(nC)
Rated reverse voltage
(V)
ST
STS4DNF60L
50
15
60
Table 15.
Schottky diode manufacturer
Manufacturer
Series
Forward voltage
(V)
Rated reverse
voltage (V)
Reverse current
(uA)
ST
STPS1L40M
0.5
40
21
2
LOAD
max
IN
OUT
DSon
conduction
(max)
I
V
V
1
R
P
×
⎟⎟
⎠
⎞
⎜⎜
⎝
⎛
−
×
=
C
RSS
C
GS
--------------



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


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