Broadcom HCPL-4200-500E

The HCPL- 4200 optocoupler is designed to operate as a receiver in equipment using the 20 mA Current Loop. 20 mA current loop systems conventionally signal a logic high state by transmitting 20 mA of loop current (MARK), and signal a logic low state by allowing no more than a few milliamperes of loop current (SPACE). Optical coupling of the signal from the 20 mA current loop to the logic output breaks ground loops and provides for a very high common mode rejection. The HCPL- 4200 aids in the design process by providing guaranteed thresholds for logic high state and logic low state for the current loop, providing an LSTTL, TTL, or CMOS compatible logic interface, and providing guaranteed common mode rejection. The buffer circuit on the current loop side of the HCPL- 4200 provides typically 0.8 mA of hysteresis which increases the immunity to common mode and differential mode noise. The buffer also provides a controlled amount of LED drive current which takes into account any LED light output degradation. The internal shield allows a guaranteed 1000 V/μs common mode transient immunity.

• Data output compatible with LSTTL, TTL and CMOS
• 20 K Baud data rate at 1400 metres line length
• Guaranteed On and Off thresholds
• LED is protected from excess current
• Input threshold hysteresis
• Three-state output compatible with data buses
• Internal shield for high Common Mode Rejection
• Safety approval
• UL recognized - 3750 V rms, for 1 minute
• CSA approved
• Optically coupled 20 mA current loop transmitter, HCPL- 4100, also available

• Isolated 20 mA current
• Loop receiver in:
  • Computer peripherals
  • Industrial control equipment
  • Data communications equipment