LTC1968 - Precision Wide Bandwidth, RMS-to-DC Converter


  • High Linearity:
    0.02% Linearity Allows Simple System Calibration
  • Wide Input Bandwidth:
    Bandwidth to 1% Additional Gain Error: 500kHz
    Bandwidth to 0.1% Additional Gain Error: 150kHz
    3dB Bandwidth Independent of Input Voltage Amplitude
  • No-Hassle Simplicity:
    True RMS-DC Conversion with Only One External Capacitor
    Delta Sigma Conversion Technology
  • Ultralow Shutdown Current:
  • Flexible Inputs:
    Differential or Single Ended
    Rail-to-Rail Common Mode Voltage Range
    Up to 1VPEAK Differential Voltage
  • Flexible Output:
    Rail-to-Rail Output
    Separate Output Reference Pin Allows Level Shifting
  • Small Size:
    Space Saving 8-Pin MSOP Package

Typical Application

LTC1968 Typical Application
LTC1968 Typical Application


The LTC1968 is a true RMS-to-DC converter that uses an innovative delta-sigma computational technique. The benefits of the LTC1968 proprietary architecture, when compared to conventional log-antilog RMS-to-DC converters, are higher linearity and accuracy, bandwidth independent of amplitude and improved temperature behavior.

The LTC1968 operates with single-ended or differential input signals and accurately supports crest factors up to 4. Common mode input range is rail-to-rail. Differential input range is 1VPEAK, and offers unprecedented linearity. The LTC1968 allows hassle-free system calibration at any input voltage.

The LTC1968 has a rail-to-rail output with a separate output reference pin providing flexible level shifting; it operates on a single power supply from 4.5V to 5.5V. A low power shutdown mode reduces supply current to 0.1µA.

The LTC1968 is packaged in the space-saving MSOP package, which is ideal for portable applications.


For complete and up to date package information and drawings, please refer to our packaging page

Part Number Package Code Temp Package
LTC1968CMS8 MS-8 MS8 C 05-08-1660 RoHS
LTC1968CMS8#PBF MS-8 MS8 C 05-08-1660 RoHS
LTC1968CMS8#TR MS-8 MS8 C 05-08-1660 RoHS
LTC1968CMS8#TRPBF MS-8 MS8 C 05-08-1660 RoHS
LTC1968IMS8 MS-8 MS8 I 05-08-1660 RoHS
LTC1968IMS8#PBF MS-8 MS8 I 05-08-1660 RoHS
LTC1968IMS8#TR MS-8 MS8 I 05-08-1660 RoHS
LTC1968IMS8#TRPBF MS-8 MS8 I 05-08-1660 RoHS

LTC1968 Package Drawing

Order Info

  • Part numbers ending in PBF are lead free. Solder plated terminal finish (SnPb) versions are non-standard and special terms and conditions and pricing applies if available. Please contact LTC marketing for information.
  • Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
  • Please refer to our general ordering information or the product datasheet for more details

Package Variations and Pricing

Part Number Package Temp Price
LTC1968CMS8 MS-8 C $10.42 $7.90 No
LTC1968CMS8#PBF MS-8 C $5.21 $3.95 Yes
LTC1968CMS8#TR MS-8 C $8.02 No
LTC1968CMS8#TRPBF MS-8 C $4.01 Yes
LTC1968IMS8 MS-8 I $17.60 $13.20 No
LTC1968IMS8#PBF MS-8 I $8.80 $6.60 Yes
LTC1968IMS8#TR MS-8 I $13.32 No
LTC1968IMS8#TRPBF MS-8 I $6.66 Yes
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* The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Linear Technology sales office or authorized distributor.

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.

Part Number Description Price Documentation
DC427B-C LTC1968CMS8 | RMS to DC Converter $50.00
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