DATA SHEET

ALI25

The industry’s first 5 MSa/s 24-bit digitizer for Pyroshock applications. Two channels supporting Bridge, ICP® and voltage inputs equipped with sophisticated anti-alias filtering. Includes buffered analog output channel and advanced options for synchronisation and triggering.

ALI25 MODULE

The ALI25 is a high-bandwidth Module designed for triggered/burst acquisition for Pyro-Shock / Mechanical Shock applications.

Every channel is equipped with precise anti-alias filtering on the Signal and Sense lines, along with dedicated bridge signal conditioning. In addition, each channel features a 24-bit, 5 MSa/s ADC and a 21 MSa data buffer. Systems can be configured with 2 to over 1000 channels.

Measurement Integrity and Sensor Status prior to an event is verified with continuous: pre-trigger monitoring, summarized signal information, and sensor fault detection. Built-in Signal Conditioning for bridge-type transducers and voltage signals. Constant voltage or current excitation is programmable for each channel.

Each input channel has a buffered low-noise output channel for monitoring or acquiring sensor data via a secondary system. Measurements are triggerable by signal level and persistence, external events, data flow, or software command. This advanced set of triggering options supports multi-system synchronisation and ensures event detection.

12 Channel DECAQ

Where Used

Front Panel and Connectors

Note: All connectors are shown as if looking into the front panel’s connector or at the rear of the cable’s connector.

Front Panel
ISM: Intelligent subModule and Digital Interface connector with LEMO® 7-pin EHG.0B connector Module Pin Definition
TRG: Digital Interface connector with LEMO® 9-pin EHG.0B connector Module Pin Definition
Inx: Analog Input Channel connectors (1/2) with LEMO® 9-pin EHG.0B connectors Module Pin Definition
BOx: Buffered Analog Output connectors (1/2) with SMB connectors Module Pin Definition. Used to externally monitor the conditioned input signal

Analog Input Channels

Overview

2 channels

24-bit resolution, 5 MSa/s sampling rate per channel

Bandwidth:

  • DC – 1.0 MHz ±0.1 dB at 5 MSa/s
  • DC – 2.375 MHz -3 dB at 5 MSa/s

Modes of operation

  • Voltage input mode
  • ICP® mode 4 mA to 20 mA with 30 V compliance
  • Bridge Input Mode:
    • 2-wire plus Shield
    • 4-wire plus Shield, targeting Pyro-Shock applications
    • 6-wire plus Shield
  • Constant Current Mode

Input Ranges

  • ±(5, 2.5, 1.25) V, ±(680, 340, 160, 80, 40, 20, 10) mV

Accuracy

  • ±0.1% of full scale ±50 µV

Slew Rate

  • >50 V/µs

Memory

  • 21 M Samples per channel, 24-bit

Differential Input

  • Input impedance 2 MΩ Differential, 1 MΩ to GND

Coupling

  • DC or AC coupled

CMRR

  • DC – 100 Hz, > 85 dB

CM Voltage Range

  • ±9 V including signal

Crosstalk

  • >90 dB isolation (channel to channel)

Sense ADC

  • Continuous fault detection of the excitation lines to detect open / short circuits.
  • The ALI25 can support other applications that require more than the 4-wire Pyro-Shock applications.

Connectors

  • 9-pin LEMO® 0B.309 (one per input channel).
  • Signal+, Signal-, Excitation+, Excitation-, Sense+, Sense-. TEDS (Class 1 & 2), AGND (REF GND), CGND.
    • Separate shield through the housing or pin of the breakout cable connector (9-pin LEMO® to D-Sub 15).

Functions

Offset Control using DAC, ±2.5 V 16-bit resolution

Offset Zero

  • Software selectable Autozero routine sets ADC output to zero for a given input.
  • Can use a combination of the offset null DAC and digital correction.

Bridge Balancing

  • Current injection ±1 mA
  • Offset Nulling ±2.5 V, 16-bit DAC
  • Bridge balancing activation available through software command

Excitation Voltage and Current (16-bit DAC)

  • Differential DC 0 to ±10 V (20 V between Excitation+ & Excitation-), current monitored (limited to 90 mA per channel)
  • Bipolar Constant Current Excitation
    • 0 to ±30 mA Constant Current
    • 4-wire & 2-wire mode

Bridge Voltage insertion

  • 10 kΩ resistor may be connected to either signal arm of the bridge and is driven by a 16-bit programmable DAC. Simulated shunt resistors.

Health Check and Calibration Options

  • Programmable Internal Reference, 16-bit DAC voltage ±5 V
  • Gain Calibration. Accomplished using internal multiple precision voltage references.
  • Calibrated Reference Ladder matched to input range
  • Full path can be calibrated System to System including buffered output channel path.
  • External Calibration through DCAT ISO17025 certified system.

Sensing

  • Local | Remote | None (Pyro-Shock 4-wire applications)

Filtering

3 Stages of anti-aliasing (AA) filters:

  • Analog AA (AAA) Filtering: Provides a -0.1 dB bandwidth of 2.5 MHz with minimal passband ripple and over 100 dB attenuation for high-frequencies
  • Delta-Sigma ADC: Over-samples the signal 8 times and achieves a flat passband of up to 1.7 MHz, anti-alias filter ripple of less than ±0.00002 dB, and stopband attenuation of 86 dB
  • FIR Filters: Ensure exceptional signal integrity with a maximum passband ripple of 0.0005 dB and minimum stopband attenuation exceeding 125 dB

The ADC and FIR filters auto-track the ALI25’s decimation factor, providing optimized performance across varying data rates.

Output data rates (ODR) of: (5, 2.5, 1.25) MSa/s, (500, 250, 125, 50, 25, 12.5, 5, 2.5, 1.25) kSa/s

ALI25 FILTER CHARACTERISTICS

Sample Rate (Sa/s) Passband (Hz) Rejection Band (Hz) Atten. (dB)
5.0 M 2.4 M
 2.9 M
 >86
2.5 M 1.2 M
 1.45 M
 >86
1.25 M 600 k
 725 k
 >100
500 k 243 k
 275 k
 >100
250 k 121.5 k
 137.5 k
 >100
125 k 60.7 k
 68.75 k
 >100
50 k 24.3 k
 27.5 k
 >100
25 k 12.15 k
 13.75 k
 >100
12.5 k 6.075 k
 6.875 k
 >100
5 k 2.43 k
 2.75 k
 >100
2.5 k 1.215 k
 1.375 k
 >100
1.25 k 607
 687
 >100

DIGITAL INTERFACE

GPIO_IN1, GPIO_IN2, GPIO_IN3, GPIO_OUT0, GPIO_OUT1, GPIO_OUT2, 12 V, PWR_IN, GND (non-isolated PWR), 6 x GPIO (3 x IN, 3 x OUT)

  • 5 V compliant, 3.3 V operation
  • Communication interface to SubModules
  • Can be configured as TRIG input / output (different combinations possible)
  • Can be used for SYNC input / output
  • Can output a CLK signal
  • Can support communication over long cables with a SubModule

12 V, PWR_IN, GND (non-isolated)

  • PWR signals that can be used by ISM / PSM for processor and relay control
  • Can be used with SubModule to convert / adapt Digital interface for various requirements
  • ISM / PSM can be locally powered if far away from the main system
  • ISM / PSM detection; if present communication can read back the ID to identify the type

Trigger Options

  • Software Trigger, triggered by a software command
  • Data Flow Trigger, programmable data trigger
  • External Trigger, triggered by external pulse
  • Real Time Trigger, trigger when analog input signal reached and remains above programmable limit
  • Backplane Trigger (4 lines)
  • Synchronous snapshot monitoring of data blocks in parallel to RAM memory
  • Synchronous monitoring across all channels while system is running

Buffered Analog Output Channels

2 channels

Buffered Analog Output Channel for each Analog Input Channel. Provides a conditioned analog output signal for monitoring with a secondary acquisition system

±1.25 V into 50 Ω for a full-scale input signal

Related Cables, SubModules and Accessories

Cables

CS-ALI-A-DB15 500 (056K 500)

  • Breakout Signal Cable 500 mm (converts the 9-pin LEMO® connector to D-Sub 15)

CS-ALI-A-DB15 2000 (056K 2000)

  • Breakout Signal Cable 2000 mm (converts the 9-pin LEMO® connector to D-Sub 15)

CS-ALI-T-DB15 500 (058K 500)

  • Breakout Digital I/O Cable 500 mm (converts the 9-pin LEMO® connector to D-Sub 15)

CS-ALI-T-DB15 2000 (058K 2000)

  • Breakout Digital I/O Cable 2000 mm (converts the 9-pin LEMO® connector to D-Sub 15)

CS-ALI-T-2J 500 (068K 500)

  • Breakout Digital Trigger I/O Cable 500 mm (converts the 9-pin LEMO® connector to 2 BNC connectors)

CS-ALI-T-2J 1000 (068K 1000)

  • Breakout Digital Trigger I/O Cable 1000 mm (converts the 9-pin LEMO® connector to 2 BNC connectors)

CS-ALI-TF-5J 200 (069K 200)

  • Breakout Digital 5x Trigger I/O Cable 200 mm (converts the D-Sub 15 connector to 5 BNC connectors, Fanout cable for SM-ALI-TFCA-DB15)

CS-ALI-A-9L-BNCP 2000 (076K 2000)

  • Breakout Signal Cable (Single-ended) 2000 mm (converts the 9-pin LEMO® connector to BNC connector)

CS-ALI-A-DB15M-BNCP-2000 (077K 2000)

  • Breakout Signal Cable (Single-ended) 2000 mm (converts the D-Sub 15 connector of 056K to BNC connector)

CS-ALI-A-SMB-BNCP 1000 (038K 1000)

  • Breakout Buffer Analog Output Cable 1000 mm (converts the SMB connector to BNC connector)

Submodules

SM-ALI-TFCA-DB15 500

  • Trigger Fanout SubModule 500 mm (converts the 9-pin LEMO® connector to D-Sub 15)

SM-ALI-SALI10 TYPE K, T

  • Thermocouple to Voltage SubModule with 290 kHz bandwidth (converts the D-Sub 15 for Thermocouple Type K and T)

SM-ALI-SALI20 TYPE J

  • Thermocouple to Voltage SubModule with 290 kHz bandwidth (converts the D-Sub 15 for Thermocouple Type J)

SM-ALI-SALI30-HS TYPE K,T

  • Thermocouple to Voltage SubModule with 1 MHz bandwidth (converts the D-Sub 15 for Thermocouple Type K and T)

Accessories

RM-ALI-NALI10-20 (PIPS)

  • 19 inch RackMount Kit to secure 20x D-Sub 15 connectors in one panel

RM-ALI-NALI10-16 (PIPS)

  • 19 inch RackMount Kit to secure 16x D-Sub 15 connectors in one panel

DQ04 | 06 Grounding Kit

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© 2026 Mecalc (Pty) Ltd. QuantusSeries and the Q icon are registered trademarks of Mecalc (Pty) Ltd. Information is provided "as is" without warranties or guarantees regarding accuracy, completeness, or suitability for any purpose. Mecalc assumes no liability for its use. Specifications may change without notice.

Mecalc logo

MECALC.com

© 2026 Mecalc (Pty) Ltd. QuantusSeries and the Q icon are registered trademarks of Mecalc (Pty) Ltd. Information is provided "as is" without warranties or guarantees regarding accuracy, completeness, or suitability for any purpose. Mecalc assumes no liability for its use. Specifications may change without notice.

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