The DEI1604 Surge Blocking Module (SBM) is a high voltage, bidirectional current limiting element implemented with normally ON N-Channel Silicon Carbide JFET technology. The device is intended to be used in conjunction with a Transient Voltage Suppressor (TVS) diode to implement a current limiting / voltage clamping protection network. A fuse element is provided to implement a "Fail Safe" interface. The integrated fuse is designed to fail OPEN when the surge current exceeds time duration much greater than a normal lightning induced transient, such as a short to 115VAC aircraft power bus. Figure 2 shows the integrated fuse connections. Fuse is connected to External IO Pin. Since the bi-directional capability of the SBM, fuses can also be connected to TVS.
- Bidirectional surge protection
- Protection for Airbus A350 XWB Aircraft Lightning Induced Transients (Also as part of DO160E, Sect 22E)
- Waveform 5A: Pin Injection, 1500V/15A, 500V/500A, 300V/300A, 200V/200A and 100V/100A
- Waveform 3: Pin Injection, 100V/4A, 250V/10A, 600V/24A, 1500V/60A 1MHZ
- Waveform 2: Pin Injection, 100V/4A, 250V/10A, 750V/50A and 1600V/107A
- Low overall resistance: 1.7W
- Operating currents: ±0.45A
- Limits surge current
- 115VAC Fuse for fail safe protection
- Package: 12L DFN 6x7.7
In normal operation, the SBM acts as a low value series resistor (< 1.7Ω including JFETs and integrated fuse) and is designed to operate at currents up to ±0.45A. In surge stress operation, the TVS device conducts surge current when the surge voltage exceeds the TVS standoff voltage. The series SBM limits the surge current to few Amps, thus allowing use of small, low power, low capacitance TVS diodes to provide the voltage clamp protection.