®
MOBILE PENTIUM PROCESSOR WITH MMX™ TECHNOLOGY
4.3.3.
CONNECTION SPECIFICATIONS
Powerdown state, or transitioning from HALT to the
Normal state. All of these examples may cause
abrupt changes in the power being consumed by
the processor.
All NC pins must remain unconnected.
For reliable operation, always connect unused
inputs to an appropriate signal level. Unused active
low inputs should be connected to VCC3. Unused
active high inputs should be connected to ground.
Note that the Auto HALT Powerdown feature is
always enabled even when other power
management features are not implemented.
4.3.4.
AC TIMINGS FOR A 66-MHZ BUS
Bulk storage capacitors with a low ESR (Effective
Series Resistance) in the 10 to 100 µf range are
required to maintain a regulated supply voltage
during the interval between the time the current
load changes and the point that the regulated
power supply output can react to the change in
load. In order to reduce the ESR, it may be
necessary to place several bulk storage capacitors
in parallel.
The AC specifications given in Table 15 consist of
output delays, input setup requirements and input
hold requirements for the mobile standard 66 MHz
external bus. All AC specifications (with the
exception of those for the TAP signals and APIC
signals) are relative to the rising edge of the CLK
input.
All timings are referenced to VCC3/2 for both "0" and
"1" logic levels unless otherwise specified. Within
the sampling window, asynchronous inputs must be
stable for correct operation.
These capacitors should be placed near the
processor on both VCC2 plane and VCC3 plane to
ensure that the supply voltages stay within
specified limits during changes in the supply current
during operation.
Each valid delay is specified for a 0 pF load. The
system designer should use I/O buffer modeling to
account for signal flight time delays. Do not select a
bus fraction and clock speed which will cause the
processor to exceed its internal maximum
frequency.
For more detailed information, please contact Intel
or refer to the Mobile Pentium Processor with
MMX™ Technology: Power Supply Design
Considerations application note (Order Number
243306).
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INTEL [ INTEL ]
