Automotive-grade 1500 W TVS in DO-201
The 1.5KE27AH is a 1500 W peak pulse power TVS zener diode from Taiwan Semiconductor, part of the 1.5KE series. This rail protects 24 V automotive buses — the 23.1 V standoff sits below the nominal 24 V line, so the diode stays high-impedance during normal operation and only clamps on transients. The DO-201AA (DO-27) axial-leaded package is through-hole mounted, suitable for point-of-entry protection on power lines or heavy-duty signal lines where board space is not the constraint. The junction temperature range spans -55 °C to 175 °C, covering the full automotive ambient envelope including engine-bay hot spots.
Clamping performance and pulse handling
The 42 A peak pulse current rating at the clamping voltage of 37.5 V confirms the diode can sink substantial surge current without exceeding its thermal limit during the pulse. The device is unidirectional (single-channel zener), so it clamps only one polarity — the anode connects to ground, the cathode to the protected rail. For bidirectional protection on AC or bipolar signal lines, a pair back-to-back is needed.
Sourcing and supply posture
The base product number is 1.5KE27, and the 'H' suffix indicates the automotive-grade AEC-Q101 variant. Standard and other grade variants exist in the same 1.5KE family, but the 'AH' suffix is the one with the full automotive qualification trace.