High speed protected digital termination array

CLT01-38S4 adds to the existing current limiter family. Still focusing on power consumption savings, the whole series allows each customer to find the right solution.

The CLT01-38S4 is an octal input termination device with a high speed SPI output. Its maximum input data rate is 400 kbps while the output SPI speed is 6.25 MHz.

As in previous versions, robustness is a key feature of CLT01-38S4. The product is compliant with surge standards defined in IEC 61000-4-x.

It can run all types of sensor according to IEC 61131-2. Type 1 and 3 with a 2.35 mA limited current and type 2 using two inputs per sensor with the correct RREF.

Key Features

  • 8-input circuit in common ground low side topology
  • Wide range input DC voltage VI : -30 V to 35 V
  • On state threshold: < 11 V with RI = 2.2 kΩ
  • Off state threshold: Iin > 1.5 mA or Vi > 5 V
  • Protected against -30 V reverse polarity
  • Typical ILIM = 2.1 to 2.6 mA adjustable current limiters
  • Tight current tolerance including temperature compensation: ±10%
  • Serial output with an SPI communication bus
  • Clock frequency up to 6.25 MHz
  • CPHA = CPOL = 0 bus master operation
  • Multi CLT operation in daisy chain connection
  • 16-bit mode: 8 bits for data / 8 bits for control
    • Minimum capture time: 4 μs
    • Input data rate: 200 kbps/100 kHz
    • Minimum propagation transfer time: 7 μs
  • 8-bit mode: 8 bits for data
    • Minimum capture time: 2.5 μs
    • Input data rate: 400 kbps/200 kHz
    • Minimum propagation transfer time: 4 μs
  • VCC = -0.3 to +35 V with RC = 2.2 kΩ
  • Ambient temperature range: -25 to +85°C
  • Digital inputs for programmable logic controller and decentralized I/O modules
  • Benefits
    • Enables input to meet type 1, 2 and 3 characteristics of IEC 61131-2 standard
    • Compatible operation with 2 wires proximity sensor according EN 60947-5-2 standard
    • Compact board with surface mount integration and reduced count of isolated couplers
    • Reduces the count of input-output of the bus controller circuit
    • Provides energy-less input LED visual status
    • Enhanced functional reliability
    • Built-in over voltage robustness and immune data transfer
    • Reduced dissipation: 78 mW max. per channel
  • Complies with following standards (RI = 2.2 Ω, RC = 2.2 Ω, C = 33 nF):
    • Electrostatic discharge, IEC 61000-4-2:
      • ±8 kV contact discharge
      • ±15 kV air discharge
    • Electrical transient immunity IEC 61000-4-41:
      • FSCK= 6.25 MHz, ±3 kV
      • FSCK= 10 kHz, ±4 kV
    • Voltage surge IEC 61000-4-5
      • Input: ±15 kV
      • Power supply: ±2.5 kV



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DB1923 DB1923: High speed protected digital termination array 1.0 284 KB
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Technical Notes & Articles
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Software Development Tools
STM32 Open Development Environment


型号 Package Packing Type Marketing Status Unit Price (US$) * Quantity ECCN (EU) ECCN (US) Country of Origin More info Order from ST Order from Distributors
CLT01-38S4 HTSSOP38 Tube Active 1.898 50 NEC EAR99 MALAYSIA MORE INFO No availability reported, please contact our Sales office
CLT01-38S4-TR HTSSOP38 Tape And Reel Active 1.898 50 NEC EAR99 MALAYSIA MORE INFO No availability reported, please contact our Sales office

(*) Suggested Resale Price per unit (USD) for BUDGETARY USE ONLY. For quotes, prices in local currency, please contact your local ST Sales Office  or our Distributors


型号 Marketing Status Package Grade RoHS Compliance Grade Material Declaration**
CLT01-38S4 ActiveHTSSOP38IndustrialEcopack2 0 0
CLT01-38S4-TR ActiveHTSSOP38IndustrialEcopack2 0 0

(**) The Material Declaration forms available on st.com may be generic documents based on the most commonly used package within a package family. For this reason, they may not be 100% accurate for a specific device. Please contact our sales support for information on specific devices.