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MPC7447A RISC Microprocessor Hardware Specifications, Rev. 5

10 Freescale Semiconductor

Electrical and Thermal Characteristics

Figure 2 shows the undershoot and overshoot voltage on the MPC7447A.

Figure 2. Overshoot/Undershoot Voltage

The MPC7447A provides several I/O voltages to support both compatibility with existing systems and

migration to future systems. The MPC7447A core voltage must always be provided at the nominal voltage

(see Table 4) or at the supported derated voltage (see Section 5.3, “Voltage and Frequency Derating”). The

input voltage threshold for each bus is selected by sampling the state of the voltage select pins at the

negation of the signal HRESET

. The output voltage will swing from GND to the maximum voltage applied

to the OV

power pins. Table 3 provides the input threshold voltage settings. Because these settings may

change in future products, it is recommended that BVSEL be configured using resistor options, jumpers,

or some other flexible means, with the capability to reconfigure the termination of this signal in the future

if necessary.

Storage temperature range T

stg

–55 to 150 °C —

Notes:

1. Functional and tested operating conditions are given in Ta bl e 4 . Absolute maximum ratings are stress ratings only, and

functional operation at the maximums is not guaranteed. Stresses beyond those listed may affect device reliability or cause

permanent damage to the device.

2. Caution: V

/AV

must not exceed OV

by more than 1.0 V during normal operation; this limit may be exceeded for a

maximum of 20 ms during the power-on reset and power-down sequences.

3. Caution: OV

must not exceed V

/AV

by more than 2.0 V during normal operation; this limit may be exceeded for a

maximum of 20 ms during the power-on reset and power-down sequences.

4. BVSEL must be set to 0, such that the bus is in 1.8-V mode.

5. BVSEL must be set to HRESET

or 1, such that the bus is in 2.5-V mode.

6. Caution: V

must not exceed OV

by more than 0.3 V at any time including during power-on reset.

7. V

may overshoot/undershoot to a voltage and for a maximum duration as shown in Figure 2.

Table 2. Absolute Maximum Ratings

(continued)

Characteristic Symbol Maximum Value Unit Notes

GND

GND – 0.3 V

GND – 0.7 V

Not to Exceed 10%

+ 20%

+ 5%

of t

SYSCLK

1 2 ... 5 6 7 8 9 10 11 12 13 14 15 ... 55 56

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