Targeted for applications such as sensing voltages in electronic power conversion systems commonly found in motor drives, switching power supplies and renewable energy systems, as well as sensor interfaces such as NTC thermistor isolation in IGBT modules, the ACPL-C87B, C87A, and C870 are able to provide designers with a 2-V input range and high 1 G‡ input impedance.
For high-precision servo and motor drives, the ACPL-C87B (±0.5% gain tolerance) can be used. The voltage sensors features a 1V/V unity gain with low gain drift of -35ppm/˚C and non-linearity is kept to within 0.1% max. The voltage sensors include an active-high shutdown pin which reduces the IDD1 current to only 15mA during standby, which makes the sensors well-suited for battery-powered and other power-sensitive applications.
“This new family of optically-isolated voltage sensors has a high 1 G‡ input impedance, which simplifies the resistor network design by allowing higher-value resistors to be used to scale the voltage.” explained Lee Kheng Jam, Marketing Director for Optocoupler products at Avago. “As a result, it reduces loading power losses, thus achieving better system efficiency.”
Differential outputs on the new devices provide enhanced isolation-mode noise rejection, low offsets, high gain accuracy and stability, and a wide signal bandwidth of 100 kHz.
The built-in reinforced safety insulation and high CMR (common mode rejection) performance prevents erroneous voltage measurements and ensures reliable operation in a noisy environment. The optically-isolated voltage sensors have a 15 kV/µs common-mode transient immunity. Safety approvals include CSA and IEC/EN/DIN EN60747-5-5 with a VIORM of 1230 V peak. Additionally, the sensors are UL recognized with 5000 Vrms for1 minute per UL1577.
The ACPL-C87xvoltage sensors are housed in stretched 8-lead SO-8 plastic packages with 8mm creepage and clearance that meet worldwide regulatory safety standards. The sensors also have a wide operating temperature range of -40 to +105 °C.