MC9S08QA4_09 Datasheet, PDF (5/32 Pages) Freescale Semiconductor, Inc – Technical Data

3 Electrical Characteristics
Electrical Characteristics
3.1 Introduction
This chapter contains electrical and timing specifications for the MC9S08QA4 series of microcontrollers available at the time
of publication.
3.2 Absolute Maximum Ratings
Absolute maximum ratings are stress ratings only, and functional operation at the maxima is not guaranteed. Stress beyond the
limits specified in Table 2 may affect device reliability or cause permanent damage to the device. For functional operating
conditions, refer to the remaining tables in this section.
This device contains circuitry protecting against damage due to high static voltage or electrical fields; however, it is advised
that normal precautions be taken to avoid application of any voltages higher than maximum-rated voltages to this
high-impedance circuit. Reliability of operation is enhanced if unused inputs are tied to an appropriate logic voltage level (for
instance, either V_SS or V_DD) or the programmable pullup resistor associated with the pin is enabled.
Table 2. Absolute Maximum Ratings
Rating
Symbol
Value
Unit
Supply voltage
Maximum current into V_DD
Digital input voltage
Instantaneous maximum current
Single pin limit (applies to all port pins)^{1, 2, 3}
V_DD
–0.3 to 3.8
V
I_DD
120
mA
V_In
–0.3 to V_DD + 0.3
V
I_D
±25
mA
Storage temperature range
T_stg
–55 to 150
°C
1 _{Input must be current limited to the value specified. To determine the value of the required}
current-limiting resistor, calculate resistance values for positive (V_DD) and negative (V_SS) clamp
voltages, then use the larger of the two resistance values.
2 _{All functional non-supply pins are internally clamped to VSS and VDD.}
3 _{Power supply must maintain regulation within operating VDD range during instantaneous and}
operating maximum current conditions. If positive injection current (V_In > V_DD) is greater than
I_DD, the injection current may flow out of V_DD and could result in external power supply going
out of regulation. Ensure external V_DD load will shunt current greater than maximum injection
current. This will be the greatest risk when the MCU is not consuming power. Examples are: if
no system clock is present, or if the clock rate is very low (which would reduce overall power
consumption).
3.3 Thermal Characteristics
This section provides information about operating temperature range, power dissipation, and package thermal resistance. Power
dissipation on I/O pins is usually small compared to the power dissipation in on-chip logic and voltage regulator circuits, and
it is user-determined rather than being controlled by the MCU design. To take P_I/O into account in power calculations, determine
the difference between actual pin voltage and V_SS or V_DD and multiply by the pin current for each I/O pin. Except in cases of
unusually high pin current (heavy loads), the difference between pin voltage and V_SS or V_DD will be very small.
MC9S08QA4 Series MCU Data Sheet, Rev. 3
Freescale Semiconductor
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