NSI7258 Solid State Relais – A Short Introduction
The NSI7258 is a solid state relay with a breakdown voltage of 1700V and is designed for 30 mA output current in ON state. It integrates two SiC MOSFETs. The operating voltage is 1000V. In the OFF state, only a leakage current of less than 1µA drains (even at 125°C ambient temperature).
Creepage and clearance are well defined with over 8mm between the input and output pins and greater than 5.91mm between the drain pins of the MOSFETs, so that the NSI7258 SSRs can withstand a voltage of 2100V at 1mA current in the avalanche test with a duration of one minute. The DTI is 13mm.
Novosense achieves the following safety regulatory approvals with the design:
- UL recognition: 5000Vrms for 1 minute per UL1577: Single Protection, 5000Vrms Isolation voltage
- CQC certification per GB4943.1: Basic Insulation
- CSA component notice 5A: Single Protection, 500Vrms Isolation Voltage
- DIN EN IEC 60747-17 (VDE 0884-17): Basic Insulation
The SOW12 housing and pinout is pin-compatible to widely used standard relays with optocouplers. The typical switch-on time is 0.106ms (0.3ms max). The typical switch-off time is 0.006ms (0.05ms max).
The EMI performance mentioned above is reflected in a CMTI of 100kV/µs. The NSI7258 also fulfills the CISPR32 Class B and CISPR 25 Class 5 EMI limits without ferrite beads on a 2-layer PCB.