91 V zener with 500 mW dissipation — the parametric fit
Rated 91 V nominal at 500 mW maximum power dissipation, the 1N6347US/TR serves as a voltage reference or clamping element in circuits that need a stable 91 V rail. The ±5% tolerance means the actual zener voltage falls between 86.45 V and 95.55 V at the test current — a standard precision band for general-purpose regulation or overvoltage protection. The -65°C to 175°C junction temperature range covers military and industrial thermal extremes — avionics, downhole tools, or engine-bay electronics where the ambient exceeds 125°C. Reverse leakage is specified at 50 nA maximum when 69 V is applied across the junction, confirming the diode holds off well below the breakdown knee.
SQ-MELF B package — board-fit and handling
Supplied in the SQ-MELF B (surface-mount MELF) package, the 1N6347US/TR is a cylindrical, end-capped component designed for automated pick-and-place. The B variant is the standard SQ-MELF outline — the cylindrical body rolls during reflow if the solder paste footprint is not matched to the recommended land pattern, so the PCB layout should follow Microchip's application note for MELF termination geometry.