LM1949 - Injector Drive Controller

Datasheet Packaging Samples & Pricing Reliability Application Notes Knowledge Base

Features
Low voltage supply (3V-5.5V)
22 mA output drive current
No RFI radiation
Adaptable to all injector current levels
Highly accurate operation
TTL/CMOS compatible input logic levels
Short circuit protection
High impedance input
Externally set holding current, IH
Internally set peak current (4 × IH)
Externally set time-out
Can be modified for full switching operation
Available in plastic 8-pin minDIP

General Description


The LM1949 linear integrated circuit serves as an excellent control of fuel injector drive circuitry in modern automotive systems. More...


Applications


Fuel injection
Throttle body injection
Solenoid controls
Air and fluid valves
DC motor drives
  Typical Application
click for larger image


Parametric Table     expand
Parametric Table    collapse
Temperature Min -55 deg C
Temperature Max 125 deg C
Temperature Min -55 deg C
Temperature Max 125 deg C
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Typical Performance


click for larger image


Additional Resources
Application Notes (see below)



Datasheet
RoHS Compliance Information Size in KbytesDate Click link below to Download
LM1949 Injector Drive Controller 476 Kbytes 21-Nov-01 View Online
Download

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Package Availability, Models, Samples & Pricing
Part NumberPackageFactory Lead TimeModelsSamples &
Electronic
Orders
Budgetary PricingStd
Pack
Size
Package
Marking
Format
TypePinsSpec.MSL
Rating
Peak
Reflow
RoHS
Report
CAD
Symbols
WeeksQtyQty$US each
LM1949NMDIP8STD
NOPB
1
1
NA
NA
RoHS N/A Full productionN/A
Samples
Buy Now
1K+$2.05rail
of
40
NSUZXYTT
LM
1949N
16 weeks2000
LM1949 MDCUnpackaged DieLifetime buyN/A
  CALLtray
of
N/A
-
N/AN/A

Obsolete Parts

Obsolete PartAlternate Part or SupplierSourceLast Time Buy Date
LM1949M
NONE
NONE
03/10/98

General Description


The LM1949 linear integrated circuit serves as an excellent control of fuel injector drive circuitry in modern automotive systems. The IC is designed to control an external power NPN Darlington transistor that drives the high current injector solenoid. The current required to open a solenoid is several times greater than the current necessary to merely hold it open; therefore, the LM1949, by directly sensing the actual solenoid current, initially saturates the driver until the "peak" injector current is four times that of the idle or "holding" current (-). This guarantees opening of the injector. The current is then automatically reduced to the sufficient holding level for the duration of the input pulse. In this way, the total power consumed by the system is dramatically reduced. Also, a higher degree of correlation of fuel to the input voltage pulse (or duty cycle) is achieved, since opening and closing delays of the solenoid will be reduced.

Normally powered from a 5V ± 10% supply, the IC is typically operable over the entire temperature range (-55°C to +125°C ambient) with supplies as low as 3 volts. This is particularly useful under "cold crank" conditions when the battery voltage may drop low enough to deregulate the 5-volt power supply.

The LM1949 is available in the plastic miniDIP, (contact factory for other package options).

Reliability Metrics


Part Number Process EFR Reject EFR Sample Size PPM * LTA Rejects LTA Device Hours FITS MTTF (Hours)
LM1949 MDCSLM0395460028575002810823427
LM1949NSLM0395460028575002810823427

Note: The Early Failure Rates were calculated as point estimates. The Long Term Failure Rates were calculated at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress temperature of 150°C to an application temperature of 55°C.

For more information on Reliability Metrics, please click here.


More Application Notes


TitleSize in Kbytes Date Click link below to Download
AN-222: Application Note 222 Super Matched Bipolar Transistor Pair Sets New Standards for Drift and Noise 464 Kbytes 1-Oct-02 Download

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[Information as of 10-Oct-2008]