ISO774x Quad-Channel Digital Isolators

Texas Instruments' ISO774x devices are high-performance, quad-channel digital isolators with 5000 V_RMS (DW package) and 2500 V_RMS (DBQ package) isolation ratings per UL 1577. This family of devices has reinforced insulation ratings according to VDE, CSA, TUV, and CQC.

The ISO774x devices provide high electromagnetic immunity and low emissions at low power consumption, while isolating CMOS or LVCMOS digital I/Os. Each isolation channel has a logic input and output buffer separated by silicon dioxide (SiO₂) insulation barrier. This device comes with enable pins which can be used to put the respective outputs in high impedance for multi-master driving applications and to reduce power consumption. The ISO7740 device has all four channels in the same direction, the ISO7741 device has three forward and one reverse-direction channels, and the ISO7742 device has two forward and two reverse-direction channels. If the input power or signal is lost, default output is high for devices without suffix F and low for devices with suffix F.

Used in conjunction with isolated power supplies, this device helps prevent noise currents on a data bus or other circuits from entering the local ground and interfering with or damaging sensitive circuitry. Through innovative chip design and layout techniques, electromagnetic compatibility of the ISO774x devices has been significantly enhanced to ease system-level ESD, EFT, surge, and emissions compliance. The ISO774x devices are available in 16-pin SOIC and QSOP packages.