In switch-mode power supplies (SMPS), the output voltage must be regulated. The A1458 can sit on the secondary (output) side and send a feedback signal to the primary (input) side controller to adjust the duty cycle, maintaining stable voltage without creating a ground loop.
In motor driver or inverter applications, fast-switching power stages create massive
Connect Pin 8 to the 12V/24V supply. Place a pull-up resistor ( ) between Pin 8 ( VCCcap V sub cap C cap C end-sub ) and Pin 6 ( VOUTcap V sub cap O cap U cap T end-sub a1458 optocoupler datasheet
: The output is fully compatible with standard TTL and CMOS logic gates. Applications
, allowing it to interface seamlessly with various logic levels, including TTL and CMOS. Reliable Isolation : Provides a safety-critical insulation voltage of 3750 Vrms to 5000 Vrms In switch-mode power supplies (SMPS), the output voltage
Microcontroller (3.3V) A1458 Receiver (5V) ┌─────┐ ┌───┐ ┌─────┐ │ ├─── 220Ω ───┬───────┤1 4├──────┬───────────┤ │ │ │ │ │ │ │ │ │ │ │ ▼ │ │ ┼─ 10kΩ ────┤ │ │ │ GND │ │ │ (pull-up) └─────┘ │2 3├──────┘ └─────┘ └───┘ │ GND (isolated)
Never connect the input pins directly to a power source. Use a resistor to limit the current ( IFcap I sub cap F ) to around 10–20mA for longevity. Place a pull-up resistor ( ) between Pin
Need help comparing the A1458 to a modern drop-in replacement? Let me know your specific use case (e.g., motor drive, SMPS feedback, or Arduino isolation).