LTR34 Multi-channel DAC for static and dynamic analog control systems

Multi-channel DAC for static and dynamic analog control systems
  • The module is used for high-quality reproduction of constant and variable voltages with signal frequency up to units of kilohertz
  • Operating modes: synchronous streaming, asynchronous, cyclic self-oscillator (from 2 to 2 million samples per cycle)
  • Two versions are available: with 4 or 8 output channels

LTR34 is a 4/8-channel 16-bit DAC designed for use as a programmable source of constant and variable voltages in the range of ± 0 V. Each LTR34 channel has a 1:1 and 1:10 output. DAC channels are synchronous. In the streaming mode, the data output rate is up to 400 kSamples/s, in the auto-generator mode - up to 500 kSamples/s. At the autogenerator mode, the periodic signal is preloaded into the LTR34 buffer with a volume of up to 2 million samples and is reproduced from the buffer without swapping data. At asynchronous operation mode, the LTR34 always keeps the last output voltage on the outputs. The external start input with galvanic optocoupler allows to start a synchronous process of data output from the external sync signal.

Number of channels 4 (for LTR34-4) 
8 (for LTR34-8)
Possible number of parallel output channels 1, 2, 4 (for LTR34-4)
1, 2, 4, 8 (for LTR34-8)
Resolution 16 bits
Each channel has two voltage outputs with common ground Output 1:1 (±10 V range)
Output 1:10 (±1 V range)
Limits of the allowed basic reduced error of reproduction of DC voltage ±0,1 %
Limits of the permissible basic reduced error of reproduction of AC voltage of the sinusoidal form, for the N-channel mode (where N = 1, 2, 4, 8):
±0,1 % At a frequency of output voltage of 400 Hz
±0,15 % At a frequency of the output voltage from 10 Hz to 5000/N Hz (except 400 Hz)
±0,5 % At a frequency of the output voltage from 5000/N Hz to 12000/N Hz
± 1% At a frequency of the output voltage from 12000/N Hz up to 16000/N Hz
Maximum output current Not less than 25 mA (±10 V range)
Not less than 2.5 mA (±1 V range)
Long-term stability of outputs to short circuit Yes
DC output resistance 50 Ohm (±10 V range)
389 Ohm (±1 V range)
Typical value of the maximum output voltage slew rate 25 V/μs
Maximum frequency of the DAC at auto-generator mode At 1-channel mode - 500.0 kHz
At 2-channel mode - 250.0 kHz
At 4-channel mode - 125.0 kHz
At 8-channel mode - 62.5 kHz
Maximum frequency of the DAC at stream output At 1-channel mode 400.0 kHz
At 2-channel mode 200.0 kHz
At 4-channel mode 100.0 kHz
At 8-channel mode 50.0 kHz
DAC buffer Up to 2 000 000 samples
DAC external trigger synchronization input
Galvanic isolation Individual relative to other contacts of the user connector
Type of input signal Logical TTL 5-volt logic
Input current No more than 8 mA (with an input voltage of 5 V)
Galvanic isolation
See the main features of LTR modules

External signals connector

Hardware description, assignment and connection of signals is given in the User's Guide.

  • LTR34-4
    DAC 4 channels, up to 500 kilo-samples/s, outputs ±10 V or ±1 V
  • LTR34-8
    DAC 8 channels, up to 500 kilo-samples/s, outputs ±10 V or ±1 V


  • ltr34api.pdf (filesize: 552 445 bytes, date: 10.06.2009)

    LTR34 module. Programmer's Guide.

  • ltrapi_en.pdf (filesize: 604 618 bytes, date: 15.02.2018)

    Ltrapi basic library. Programmer's Guide.

  • ltr_cross_sdk_en.pdf (filesize: 551 553 bytes, date: 13.02.2018)

    Description of the software for Windows, Linux, FreeBSD and QNX.

  • ltr_en.pdf (filesize: 11 066 427 bytes, date: 25.12.2017)

    LTR modular DAQ system. User's Guide (revision 3.1.0).

    • General characteristics and principles of construction
    • Working with LTR crate
    • Overview of LTR crate architecture
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    • LTR24 (-1, -2) ADC modules
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    • LTR34 DAC module
    • LTR35 DAC module
    • LTR114 ADC module
    • LTR210 ADC module
    • LTR00 Dummy module
    • Low-level programming of LTR-EU crate
    • Specification
  • ltr_soft_getting_started_en.pdf (filesize: 269 974 bytes, date: 13.02.2018)

    Starting to work with DAQ system LTR. Questions about the software.

Software for Windows

  • lcard-opc-setup.exe (filesize: 12 440 520 bytes, date: 09.04.2019)

    OPC DA Server for L Card data acquisition modules and LTR crate system. Version 1.0.10.

  • lcomp.exe (filesize: 6 342 216 bytes, date: 12.05.2021)

    Beta version. LCOMP library for Windows XP/Vista/Win7/Win8/Win10 32 and 64-bit versions with drivers. The installer and drivers are digitally signed. The library is built on the basis of modern WDM-drivers rewritten on WDF. It includes the WDM driver itself for L-CARD hardware, the DLL library with source code, programming examples, electronic description, etc. The LCOMP library provides support for almost the entire range of products: PCI boards, USB modules. ISA support is excluded.

    The library includes “L-Graph I” software. L-Graph I supports the following devices: L-1450, L-761, L-780, L-783, L-791, E14-140, E-154 and E14-440. Files recorded by L-Graph I can also be read and processed using the demo-version of PowerGraph v.3.X.

  • ltrd-setup.exe (filesize: 1 467 408 bytes, date: 19.08.2021)

    The ltrd service. Version Provides communication with LTR crates. It is a replacement for the LTRserver software while maintaining the compatibility of the program interface. ltrd is designed for the same purpose as LTRserver, but it is a service that runs when the system is started. The graphical interface to the service is provided by a separate LTR Manager program.

    Attention! Only one of the programs ltrd or LTRserver can work at a time.

  • ltrdll.exe (filesize: 1 328 600 bytes, date: 30.11.2021)

    Libraries for working with LTR crates and modules. Version 1.32.30.

  • ltrmanager_setup.exe (filesize: 9 751 808 bytes, date: 04.05.2021)

    LTR Manager software. Version 1.5.2. Graphical interface to the ltrd service. Provides an interface similar to the LTRserver interface when working through the ltrd service.


Phone: +7 (495) 785-95-19
Fax: +7 (495) 785-95-14

Sales department:
Technical support:

5 Varshavskoye shosse, corp. 4, build. 2
Moscow 117105
Russian Federation

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More than 3,000 customers worldwide are already using L-CARD electronic equipment for a wide range of research and industrial applications. We are glad to help you at any stage of creating an electronic product: from development and production to post-warranty support.



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