The STMicroelectronics ESDA6V1M6 is listed as obsolete.
What this ESD protector does
The ESDA6V1M6 is a Zener-type ESD suppressor from ST's TRANSIL™ family, packaged in a 6-UFDFN (6-µQFN 1.45x1.0 mm) for surface-mount assembly. The 70 pF capacitance at 1 MHz is moderate — suitable for general-purpose signal lines up to a few MHz, but may load higher-speed interfaces like USB 2.0 or Gigabit Ethernet. Peak pulse power is rated at 100 W.
Key specs at a glance
Four unidirectional channels in a single 6-µQFN package save board space compared to four discrete Zener diodes. The 70 pF per channel is a design parameter — if your signal edge rate is fast (sub-ns rise times), this capacitance will degrade the eye diagram; for I²C, GPIO, or button inputs it is fine.