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Single-channel Isolated 24-V to 60-V digital input receiver for digital input modules

Availability: 613


Package | PIN: SOIC (D) | 8
Temp: Q (-40 to 125)
Package qty | Carrier: 75 | TUBE
Qty Price
1-99 $0.71
100-249 $0.62
250-999 $0.42
1,000+ $0.32


  • Compliant to IEC 61131-2; Type 1, 2, 3 Characteristics for 24-V Isolated Digital Inputs
  • Supports 9-V to 300-V DC and AC Digital Input Designs Using External Resistors
  • Accurate Current Limit for Low-Power Dissipation:
    • 2.2 mA to 2.47 mA for Type 3
    • Adjustable up to 6.5 mA
  • Eliminates the Need for Field-Side Power Supply
  • High Input-Voltage Range With Reverse Polarity Protection: ±60 V
  • Wire-Break Detection (Refer to TIDA-01509)
  • Configurable as Sourcing or Sinking Input
  • High Data Rates: Up to 4 Mbps
  • Enable Pin to Multiplex Output Signals
  • High Transient Immunity: ±70-kV/µs CMTI
  • Wide Supply Range (VCC1): 2.25 V to 5.5 V
  • Ambient Temperature Range: –40°C to +125°C
  • Compact Package Options:
    • Single-Channel ISO1211, SOIC-8
    • Dual-ChannelISO1212, SSOP-16
  • Safety-Related Certifications:
    • Basic Insulation per DIN V VDE V0884-10
    • UL 1577 Recognition, 2500-VRMS Insulation
    • CSA, CQC, TUV CertificatesAvailable

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Texas Instruments  ISO1211D

The ISO1211 and ISO1212 devices are isolated 24-V to 60-Vdigital input receivers, compliant to IEC 61131-2 Type 1, 2, and 3 characteristics. These devicesenable 9-V to 300-V DC and AC digital input modules in programmable logic controllers (PLCs),motor-control, grid infrastructure, and other industrial applications. Unlike traditionaloptocoupler solutions with discrete, imprecise current limiting circuitry, theISO121x devices provide asimple, low-power solution with an accurate current limit to enable the design of compact andhigh-density I/O modules. These devices do not require field-side power supply and are configurableas sourcing or sinking inputs.

The ISO121x devicesoperate over the supply range of 2.25 V to 5.5 V, supporting 2.5-V, 3.3-V, and 5-V controllers. A±60-V input tolerance with reverse polarity protection helps ensure the input pins are protected incase of faults with negligible reverse current. These devices support up to 4-Mbps data ratespassing a minimum pulse width of 150 ns for high-speed operation. The ISO1211 device is ideal for designsthat require channel-to-channel isolation and the ISO1212 device is ideal formultichannel space-constrained designs.

The ISO121x devicesreduce component count, simplify system design, improve performance, and reduce board temperaturescompared to traditional solutions. For details, refer to the How To Simplify Isolated 24-V PLC Digital Input ModuleDesigns TI TechNote, How To Improve Speed and Reliability of Isolated Digital Inputs in MotorDrives TI TechNote, and How to Design Isolated Comparators for ±48V, 110V and 240V DC and ACDetection TI TechNote.