поискавой системы для электроныых деталей
  Russian  ▼
ALLDATASHEETRU.COM

X  

LM1949 датащи(PDF) 7 Page - National Semiconductor (TI)

[Old version datasheet] Texas Instruments acquired National semiconductor. Click here to check the latest version.
номер детали LM1949
подробное описание детали  LM1949 Injector Drive Controller
Download  10 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
производитель  NSC [National Semiconductor (TI)]
домашняя страница  http://www.national.com
Logo NSC - National Semiconductor (TI)

LM1949 датащи(HTML) 7 Page - National Semiconductor (TI)

Back Button LM1949 Datasheet HTML 2Page - National Semiconductor (TI) LM1949 Datasheet HTML 3Page - National Semiconductor (TI) LM1949 Datasheet HTML 4Page - National Semiconductor (TI) LM1949 Datasheet HTML 5Page - National Semiconductor (TI) LM1949 Datasheet HTML 6Page - National Semiconductor (TI) LM1949 Datasheet HTML 7Page - National Semiconductor (TI) LM1949 Datasheet HTML 8Page - National Semiconductor (TI) LM1949 Datasheet HTML 9Page - National Semiconductor (TI) LM1949 Datasheet HTML 10Page - National Semiconductor (TI)  
Zoom Inzoom in Zoom Outzoom out
 7 / 10 page
background image
POWER DISSIPATION
The power dissipation of the system shown in
Figure 1 is
dependent upon several external factors including the fre-
quency and duty cycle of the input waveform to Pin 1 Cal-
culations are made more difficult since there are many dis-
continuities and breakpoints in the power waveforms of the
various components most notably at the peak-to-hold tran-
sition Some generalizations can be made for normal opera-
tion For example in a typical cycle of operation the majori-
ty of dissipation occurs during the hold state The hold state
is usually much longer than the peak state and in the peak
state nearly all power is stored as energy in the magnetic
field of the injector later to be dumped mostly through the
zener While this assumption is less accurate in the case of
low battery voltage it nevertheless gives an unexpectedly
accurate set of approximations for general operation
The following nomenclature refers to
Figure 1 Typical val-
ues are given in parentheses
RS
e
Sense Resistor (01X)
VH
e
Sense Input Hold Voltage (094V)
Vp
e
Sense Input Peak Voltage (385V)
VZ
e
Z1 Zener Breakdown Voltage (33V)
VBATT
e
Battery Voltage (14V)
L1
e
Injector Inductance (002H)
R1
e
Injector Resistance (1X)
n
e
Duty Cycle of Input Voltage of Pin 1 (0 to 1)
f
e
Frequency of Input (10Hz to 200Hz)
Q1 Power Dissipation
PQ
n
 VBATT 
VH
RS
Watts
Zener Dissipation
PZ
VZ  L1  f 
(VP2 a VH2)
((VZ-VBATT)  RS2)
Watts
Injector Dissipation
PI
n
 R1 
VH2
RS2
Watts
Sense Resistor
PR
n
VH2
RS2
Watts
PR (worst case)
n
VP2
RS2
Watts
SWITCHING INJECTOR DRIVER CIRCUIT
The power dissipation of the system and especially of Q1
can be reduced by employing a switching injector driver cir-
cuit Since the injector load is mainly inductive transistor Q1
can be rapidly switched on and off in a manner similar to
switching regulators The solenoid inductance will naturally
integrate the voltage to produce the required injector cur-
rent while the power consumed by Q1 will be reduced A
note of caution The large amplitude switching voltages that
are present on the injector can and do generate a tremen-
dous amount of radio frequency interference (RFI) Because
of this switching circuits are not recommended The extra
cost of shielding can easily exceed the savings of reduced
power In systems where switching circuits are mandatory
extensive field testing is required to guarantee that RFI can-
not create problems with engine control or entertainment
equipment within the vicinity
The LM1949 can be easily modified to function as a switch-
er Accomplished with the circuit of
Figure 7 the only addi-
tional components required are two external resistors RA
and RB Additionally the zener needs to be reconnected as
shown to RS The amount of ripple on the hold current is
easily controlled by the resistor ratio of RA to RB RB is kept
small so that sense input bias current (typically 03 mA) has
negligible effect on VH Duty cycle and frequency of oscilla-
tion during the hold state are dependent on the injector
characteristics RA RB and the zener voltage as shown in
the following equations
Hold Current
VH
RS
Minimum Hold Current
VHbRBR
A
 VZ
J
RS
Ripple or DI Hold
RB
RA
 VZ 
1
RS
fo
RS
L1

RA
RB

VBATT
VZ

1bVBATT
VZ
J
fo e Hold State Oscillation Frequency
Duty Cycle of fo
VBATT
VZ
Component Power Dissipation
PQ
n

1bVBATT
VZ
J VSAT
RS
 VH
VSAT e Q1 Saturation Volt
E
1 Amp (15V)
PZ
n

VBATT  VH
RS
PRA
VB  VZ
R1
As shown the power dissipation by Q1 in this manner is
substantially reduced Measurements made with a thermo-
couple on the bench indicated better than a fourfold reduc-
tion in power in Q1 However the power dissipation of the
zener (which is independent of the zener voltage chosen) is
increased over the circuit of
Figure 1
TLH5062 – 9
FIGURE 6 Switching Waveforms
7


Аналогичный номер детали - LM1949

производительномер деталидатащиподробное описание детали
logo
Texas Instruments
LM1949 TI1-LM1949 Datasheet
791Kb / 17P
[Old version datasheet]   Injector Drive Controller
LM1949 TI-LM1949 Datasheet
766Kb / 17P
[Old version datasheet]   LM1949 Injector Drive Controller
REVISED MARCH 2013
LM1949N TI-LM1949N Datasheet
766Kb / 17P
[Old version datasheet]   LM1949 Injector Drive Controller
REVISED MARCH 2013
LM1949N/NOPB TI1-LM1949N/NOPB Datasheet
791Kb / 17P
[Old version datasheet]   Injector Drive Controller
More results

Аналогичное описание - LM1949

производительномер деталидатащиподробное описание детали
logo
Texas Instruments
LM1949 TI-LM1949 Datasheet
766Kb / 17P
[Old version datasheet]   LM1949 Injector Drive Controller
REVISED MARCH 2013
LM1949 TI1-LM1949 Datasheet
791Kb / 17P
[Old version datasheet]   Injector Drive Controller
logo
Yuan Dean Scientific., ...
PE101G YUANDEAN-PE101G Datasheet
564Kb / 2P
   POE Injector
logo
PHOENIX CONTACT
2703007 PHOENIX-2703007 Datasheet
986Kb / 29P
   Injector - INJ 1010
Dec 6, 2022
logo
Level One
POI-3000 LVL1-POI-3000 Datasheet
628Kb / 3P
   Gigabit PoE Injector
logo
Shenzhen Huazhimei Semi...
HM1642 HMSEMI-HM1642 Datasheet
672Kb / 7P
   LED Drive controller
logo
Advanced Technical Mate...
DI17X ATM-DI17X Datasheet
54Kb / 1P
   OUTLINE DC INJECTOR
logo
Level One
POI-2001 LVL1-POI-2001 Datasheet
1Mb / 2P
   Gigabit PoE Injector
logo
PHOENIX CONTACT
2703005 PHOENIX-2703005 Datasheet
1Mb / 34P
   Injector - INJ 1000
2703008 PHOENIX-2703008 Datasheet
987Kb / 29P
   Injector - INJ 1010-T
Dec 6, 2022
More results


Html Pages

1 2 3 4 5 6 7 8 9 10


датащи скачать

Go To PDF Page


ссылки URL




Конфиденциальность
ALLDATASHEETRU.COM
Вашему бизинису помогли Аллдатащит?  [ DONATE ] 

Что такое Аллдатащит   |   реклама   |   контакт   |   Конфиденциальность   |   обмен ссыками   |   поиск по производителю
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