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LM2907

    Frequency to Voltage Converter
Generic P/N 2907

Contents

Parametric Table
 Function   Frequency to Voltage 

General Description

The LM2907, LM2917 series are monolithic frequency to voltage converters with a high gain op amp/comparator designed to operate a relay, lamp, or other load when the input frequency reaches or exceeds a selected rate. The tachometer uses a charge pump technique and offers frequency doubling for low ripple, full input protection in two versions (LM2907-8, LM2917-8) and its output swings to ground for a zero frequency input.

The op amp/comparator is fully compatible with the tachometer and has a floating transistor as its output. This feature allows either a ground or supply referred load of up to 50 mA. The collector may be taken above VCC up to a maximum VCE of 28V.

The two basic configurations offered include an 8-pin device with a ground referenced tachometer input and an internal connection between the tachometer output and the op amp non-inverting input. This version is well suited for single speed or frequency switching or fully buffered frequency to voltage conversion applications.

The more versatile configurations provide differential tachometer input and uncommitted op amp inputs. With this version the tachometer input may be floated and the op amp becomes suitable for active filter conditioning of the tachometer output.

Both of these configurations are available with an active shunt regulator connected across the power leads. The regulator clamps the supply such that stable frequency to voltage and frequency to current operations are possible with any supply voltage and a suitable resistor.


Features

  • Ground referenced tachometer input interfaces directly with variable reluctance magnetic pickups
  • Op amp/comparator has floating transistor output
  • 50 mA sink or source to operate relays, solenoids, meters, or LEDs
  • Frequency doubling for low ripple
  • Tachometer has built-in hysteresis with either differential input or ground referenced input
  • Built-in zener on LM2917
  • ±0.3% linearity typical
  • Ground referenced tachometer is fully protected from damage due to swings above VCC and below ground

Applications

  • Over/under speed sensing
  • Frequency to voltage conversion (tachometer)
  • Speedometers
  • Breaker point dwell meters
  • Hand-held tachometer
  • Speed governors
  • Cruise control
  • Automotive door lock control
  • Clutch control
  • Horn control
  • Touch or sound switches

Datasheet

TitleSize
(in Kbytes)
Date
View Online

Download

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LM2907/LM2917 Frequency to Voltage Converter 623 Kbytes 7-Jun-00 View Online Download Receive via Email

Please use Adobe Acrobat to view PDF file(s).
If you have trouble printing, see Printing Problems.


Package Availability, Models, Samples & Pricing

Part NumberPackageStatusModelsSamples
&
Electronic
Orders
Budgetary PricingStd
Pack
Size
Package
Marking
Type# pinsSPICEIBISQuantity$US each
LM2907M-8SOIC NARROW8Full productionN/AN/ASamples
Buy Now
1K+$0.8000tube
of
95
[logo]¢2¢T
LM29
07M-8
LM2907MX-8SOIC NARROW8Full productionN/AN/A 
Buy Now
1K+$0.8000reel
of
2500
[logo]¢2¢T
LM29
07M-8
LM2907MSOIC NARROW(MCM)14Full productionN/AN/ASamples
Buy Now
1K+$0.8000tube
of
55
[logo]¢U¢Z¢2¢T
LM2907M
LM2907MXSOIC NARROW(MCM)14Full productionN/AN/A 
Buy Now
1K+$0.8000reel
of
2500
[logo]¢U¢Z¢2¢T
LM2907M
LM2907N-8MDIP8Full productionN/AN/A24 Hour Samples
Buy Now
1K+$0.8000tube
of
40
[logo]¢U¢Z¢2¢T
LM
2907N-8
LM2907NMDIP(MCM)14Full productionN/AN/A24 Hour Samples
Buy Now
1K+$0.8000tube
of
25
[logo]¢U¢Z¢3¢T
LM2907N

Application Notes

TitleSize
(in Kbytes)
Date
View Online

Download

Receive via Email
AN-162: LM2907 Tachometer/Speed Switch Building Block Applications 309 Kbytes 4-Nov-95 View Online Download Receive via Email

Please use Adobe Acrobat to view PDF file(s).
If you have trouble printing, see Printing Problems.


[Information as of 27-Oct-2001]
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