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Subject: Electrical interface and startup data for SANYO DENKI 9G0612P4S001

We are evaluating two 9G0612P4S001 fans in a 12V system (10.8 to 13.2V
system supply). Please provide specifications explicitly applicable to
this complete part number, including temperature and voltage conditions:

1. PWM input: recommended frequency range, VIH/VIL, absolute maximum
   voltage, open-circuit voltage, maximum source current, input leakage
   and behavior when the fan is unpowered. Can two inputs share one
   open-drain driver? Is 0% duty guaranteed to keep running?
2. Pulse sensor: output topology, pulses per revolution, maximum pull-up
   voltage, sink current, guaranteed VOL, off-state leakage, rise/fall
   times, and output behavior during power-up, power-down and rotor lock.
3. Supply: maximum operating current (not nominal rated current), startup
   peak current and duration, input capacitance/inrush, locked-rotor
   current and automatic restart pulse/retry timing, and minimum off-time
   before restart. Please include worst cases over the operating range.
4. Are the published general PWM/pulse-sensor example limits guaranteed
   for 9G0612P4S001? If so, please identify the governing document/revision.
5. Please supply recommended branch protection, permissible supply ramp,
   signal connection order, and any restrictions on live connection.

Current interface for review:
- Fan power switched by a common high-side MOSFET; fan grounds stay fixed.
- PWM: shared open-drain NMOS, nominal 25kHz.
- Each yellow sensor wire: 10k pull-up to switched fan power; 15k series
  to an NMOS gate, 10k gate-to-ground. The NMOS drain has a separate
  10k pull-up to 3.3V and drives its own MCU input.
- Red=power, black=ground, yellow=pulse sensor, brown=PWM.

Please identify any interface restrictions that make this circuit
incompatible. We have not treated the family example limits or the
0.67A rated current as guaranteed model-specific worst-case values.