MC9S08JS16 FREESCALE [Freescale Semiconductor, Inc], MC9S08JS16 Datasheet - Page 7

• Manufacturer Part Number: MC9S08JS16
• Description: Technical Data
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

3.3
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 it is user-determined rather than being controlled by the MCU design. In order to take
P
V
loads), the difference between pin voltage and V
The average chip-junction temperature (T
where:
T
θ
Freescale Semiconductor
JA
I/O
A
DD
= Ambient temperature, °C
= Package thermal resistance, junction-to-ambient, °C/W
into account in power calculations, determine the difference between actual pin voltage and V
and multiply by the pin current for each I/O pin. Except in cases of unusually high pin current (heavy
Thermal Characteristics
1
2
3
1
2
3
4
Operating temperature range (packaged)
Thermal resistance
24-pin QFN
20-pin SOIC
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
voltages, then use the larger of the two resistance values.
All functional non-supply pins are internally clamped to V
Power supply must maintain regulation within operating V
operating maximum current conditions. If positive injection current (V
I
out of regulation. Ensure external V
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.
Junction temperature is a function of die size, on-chip power dissipation, package thermal
resistance, mounting site (board) temperature, ambient temperature, air flow, power dissipation
of other components on the board, and board thermal resistance
Junction to Ambient Natural Convection
1s — Single layer board, one signal layer
2s2p — Four layer board, 2 signal and 2 power layers
DD
, the injection current may flow out of V
1,2,3,4
MC9S08JS16 Series MCU Data Sheet, Rev. 4
Rating
Table 4. Thermal Characteristics
T
J
J
) in °C can be obtained from:
= T
DD
A
load will shunt current greater than maximum injection
+ (P
SS
DD
or V
D
and could result in external power supply going
× θ
2s2p
2s2p
DD
JA
1s
1s
)
will be very small.
SS
DD
Symbol
and V
range during instantaneous and
θ
T
JA
A
DD
DD
) and negative (V
.
In
> V
-40 to 85
T
Value
L
DD
92
33
86
58
to T
) is greater than
H
Electrical Characteristics
SS
) clamp
°C/W
Unit
°C
SS
Eqn. 1
or
7