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9.0 Electrical Specifications (Continued)

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9.8 Reset Timing

Note: Software Reset should be initiated no sooner then 500 µs after power-up or the deassertion of hardware reset.

Note: It is important to choose pull-up and/or pull-down resistors for each of the hardware configuration pins that provide fast RC time constants in order to

latch-in the proper value prior to the pin transitioning to an output driver.

Note: The timing for Hardware Reset Option 2 is equal to parameter T1 plus parameter T2 (501 µs total).

Parameter Description Notes Min Typ Max Units

T8.23.1 Internal Reset Time 500 µs

T8.23.2 Hardware RESET Pulse Width 1 µs

T8.23.3 Post Reset Stabilization time

prior to MDC preamble for reg-

ister accesses

MDIO is pulled high for 32 bit serial man-

agement initialization

500 µs

T8.23.4 Hardware Configuration Latch-

in Time from the Deassertion of

Reset (either soft or hard)

Hardware Configuration Pins are de-

scribed in the Pin Description section

800 ns

T8.23.5 Hardware Configuration pins

transition to output drivers

It is important to choose pull-up and/or

pull-down resistors for each of the hard-

ware configuration pins that provide fast

RC time constants in order to latch-in the

proper value prior to the pin transitioning

to an output driver

800 ns

VCC

HARDWARE

RESET (OPTION #1)

MDC

32 CLOCKS

LATCH-IN OF HARDWARE

CONFIGURATION PINS

DUAL FUNCTION PINS

BECOME ENABLED AS OUTPUTS

INPUT OUTPUT

HARDWARE

RESET (OPTION #2)

T8.23.5

T8.23.