Zakładka z wyszukiwarką danych komponentów
  Polish  ▼
ALLDATASHEET.PL

X  

ADP3418 Arkusz danych(PDF) 10 Page - Analog Devices

Numer części ADP3418
Szczegółowy opis  Dual Bootstrapped 12 V MOSFET Driver with Output Disable
Download  16 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Producent  AD [Analog Devices]
Strona internetowa  http://www.analog.com
Logo AD - Analog Devices

ADP3418 Arkusz danych(HTML) 10 Page - Analog Devices

Back Button ADP3418 Datasheet HTML 6Page - Analog Devices ADP3418 Datasheet HTML 7Page - Analog Devices ADP3418 Datasheet HTML 8Page - Analog Devices ADP3418 Datasheet HTML 9Page - Analog Devices ADP3418 Datasheet HTML 10Page - Analog Devices ADP3418 Datasheet HTML 11Page - Analog Devices ADP3418 Datasheet HTML 12Page - Analog Devices ADP3418 Datasheet HTML 13Page - Analog Devices ADP3418 Datasheet HTML 14Page - Analog Devices Next Button
Zoom Inzoom in Zoom Outzoom out
 10 / 16 page
background image
ADP3418
Rev. B | Page 10 of 16
APPLICATION INFORMATION
SUPPLY CAPACITOR SELECTION
For the supply input (VCC) of the ADP3418, a local bypass
capacitor is recommended to reduce the noise and to supply
some of the peak currents drawn. Use a 4.7 µF, low ESR
capacitor. Multilayer ceramic chip (MLCC) capacitors provide
the best combination of low ESR and small size. Keep the
ceramic capacitor as close as possible to the ADP3418.
BOOTSTRAP CIRCUIT
The bootstrap circuit uses a charge storage capacitor (CBST) and
a diode, as shown in Figure 1. These components can be
selected after the high-side MOSFET has been chosen. The
bootstrap capacitor must have a voltage rating that is able to
handle twice the maximum supply voltage. A minimum 50 V
rating is recommended. The capacitor values are determined
using the following equations:
GATE
GATE
BST2
BST1
V
Q
C
C
×
=
+
10
(1)
D
GATE
BST2
BST1
BST1
V
VCC
V
C
C
C
=
+
(2)
where QGATE is the total gate charge of the high-side MOSFET at
VGATE, VGATE is the desired gate drive voltage (usually in the
range of 5-10 V, 7 V being typical), and VD is the voltage drop
across D1. Rearranging Equations 1 and 2 to solve for CBST1
yields
D
GATE
BST1
V
VCC
Q
C
×
= 10
CBST2 can then be found by rearranging Equation 1:
1
10
BST
GATE
GATE
BST2
C
V
Q
C
×
=
For example, an NTD60N02 has a total gate charge of about
12 nC at VGATE = 7 V. Using VCC = 12 V and VD = 1 V, we find
CBST1 = 12 nF and CBST2 = 6.8 nF. Good quality ceramic
capacitors should be used.
RBST is used for slew-rate limiting to minimize the ringing at the
switch node. It also provides peak current limiting through D1.
An RBST value of 1.5 Ω to 2.2 Ω is a good choice. The resistor
needs to be able to handle at least 250 mW due to the peak
currents that flow through it.
A small-signal diode can be used for the bootstrap diode due to
the ample gate drive voltage supplied by VCC. The bootstrap
diode must have a minimum 15 V rating to withstand the
maximum supply voltage. The average forward current can be
estimated by
MAX
GATE
AVG
F
f
Q
I
×
=
)
(
(3)
where fMAX is the maximum switching frequency of the
controller. The peak surge current rating should be calculated
using:
BST
D
PEAK
F
R
V
VCC
I
=
)
(
(4)
MOSFET SELECTION
When interfacing the ADP3418 to external MOSFETs, there are
a few considerations that the designer should be aware of. These
will help to make a more robust design that will minimize
stresses on both the driver and MOSFETs. These stresses
include exceeding the short-time duration voltage ratings on
the driver pins as well as the external MOSFET.
It is also highly recommended to use the Boot-Snap circuit to
improve the interaction of the driver with the characteristics of
the MOSFETs. If a simple bootstrap arrangement is used, make
sure to then include a proper snubber network on the SW node.
High-Side (Control) MOSFETs
The high-side MOSFET is usually selected to be high speed to
minimize switching losses (see any ADI Flex-mode™ controller
datasheet for more details on MOSFET losses). This usually
implies a low gate resistance and low input capacitance/charge
device. Yet, there is also a significant source lead inductance that
can exist (this depends mainly on the MOSFET package; it is
best to contact the MOSFET vendor for this information).
The ADP3418 DRVH output impedance and the input
resistance of the MOSFETs determine the rate of charge
delivery to the gate’s internal capacitance, which determines the
speed at which the MOSFETs turn on and off. However, due to
potentially large currents flowing in the MOSFETs at the on and
off times (this current is usually larger at turn off due to
ramping up of the output current in the output inductor), the
source lead inductance will generate a significant voltage across
it when the high-side MOSFETs switch off. This will create a
significant drain-source voltage spike across the internal die of
the MOSFETs and can lead to catastrophic avalanche. The
mechanisms involved in this avalanche condition can be
referenced in literature from the MOSFET suppliers.


Podobny numer części - ADP3418

ProducentNumer częściArkusz danychSzczegółowy opis
logo
ON Semiconductor
ADP3418 ONSEMI-ADP3418 Datasheet
308Kb / 13P
   Dual Bootstrapped, 12 V MOSFET Driver with Output Disable
May 2010 ??Rev. 6
ADP3418KRZ ONSEMI-ADP3418KRZ Datasheet
308Kb / 13P
   Dual Bootstrapped, 12 V MOSFET Driver with Output Disable
May 2010 ??Rev. 6
ADP3418KRZ-REEL ONSEMI-ADP3418KRZ-REEL Datasheet
308Kb / 13P
   Dual Bootstrapped, 12 V MOSFET Driver with Output Disable
May 2010 ??Rev. 6
More results

Podobny opis - ADP3418

ProducentNumer częściArkusz danychSzczegółowy opis
logo
ON Semiconductor
NCP3418 ONSEMI-NCP3418 Datasheet
90Kb / 10P
   Dual Bootstrapped 12 V MOSFET Driver with Output Disable
May, 2004 ??Rev. 10
NCP3418 ONSEMI-NCP3418_06 Datasheet
110Kb / 9P
   Dual Bootstrapped 12 V MOSFET Driver with Output Disable
May, 2006 ??Rev. 12
logo
Analog Devices
ADP3650 AD-ADP3650 Datasheet
279Kb / 12P
   Dual, Bootstrapped, 12 V MOSFET Driver with Output Disable
REV. A
logo
ON Semiconductor
ADP3121 ONSEMI-ADP3121 Datasheet
147Kb / 10P
   Dual Bootstrapped, 12 V MOSFET Driver with Output Disable
April, 2009 ??Rev. 0
logo
Analog Devices
ADP3120A AD-ADP3120A Datasheet
292Kb / 16P
   Dual Bootstrapped, 12 V MOSFET Driver with Output Disable
REV. 0
logo
ON Semiconductor
ADP3110A ONSEMI-ADP3110A Datasheet
132Kb / 8P
   Dual Bootstrapped, 12 V MOSFET Driver with Output Disable
August, 2008 ??Rev. 4
logo
Analog Devices
ADP3110 AD-ADP3110 Datasheet
245Kb / 12P
   Dual Bootstrapped, 12 V MOSFET Driver with Output Disable
REV. 0
logo
ON Semiconductor
ADP3418 ONSEMI-ADP3418 Datasheet
308Kb / 13P
   Dual Bootstrapped, 12 V MOSFET Driver with Output Disable
May 2010 ??Rev. 6
NCP3418BDR2G ONSEMI-NCP3418BDR2G Datasheet
255Kb / 9P
   Dual Bootstrapped 12 V MOSFET Driver with Output Disable
April, 2007 -- Rev. 13
logo
Analog Devices
ADP3120 AD-ADP3120 Datasheet
272Kb / 16P
   Dual Bootstrapped 12 V MOSFET Driver with Output Disable
REV. 0
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16


Arkusz danych Pobierz

Go To PDF Page


Link URL




Polityka prywatności
ALLDATASHEET.PL
Czy Alldatasheet okazała się pomocna?  [ DONATE ] 

O Alldatasheet   |   Reklama   |   Kontakt   |   Polityka prywatności   |   Linki   |   Lista producentów
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