Motorola MC9S12C-Family, MC9S12GC-Family warranty Power Dissipation and Thermal Characteristics

Device User Guide — 9S12C128DGV1/D V01.05

NOTE: Instead of specifying ambient temperature all parameters are specified for the more meaningful silicon junction temperature. For power dissipation calculations refer to Section A.1.8 Power Dissipation and Thermal Characteristics.

Table A-4 Operating Conditions

Rating	Symbol	Min	Typ	Max	Unit
I/O, Regulator and Analog Supply Voltage	VDD5	2.97	5	5.5	V
Digital Logic Supply Voltage1	VDD	2.35	2.5	2.75	V
PLL Supply Voltage (1)	VDDPLL	2.35	2.5	2.75	V
Voltage Difference VDDX to VDDA	ΔVDDX	-0.1	0	0.1	V
Voltage Difference VSSX to VSSR and VSSA	ΔVSSX	-0.1	0	0.1	V
Oscillator	fosc	0.5	-	16	MHz
Bus Frequency	2	0.25	-	25	MHz
	fbus
Operating Junction Temperature Range	T	-40	-	140	°
	J				C
NOTES:

1.The device contains an internal voltage regulator to generate the logic and PLL supply out of the I/O supply. The absolute maximum ratings apply when this regulator is disabled and the device is powered from an external source.

2.Some blocks e.g. ATD (conversion) and NVMs (program/erase) require higher bus frequencies for proper oper- ation.

A.1.8 Power Dissipation and Thermal Characteristics

Power dissipation and thermal characteristics are closely related. The user must assure that the maximum operating junction temperature is not exceeded. The average chip-junction temperature (TJ) in °C can be obtained from:

TJ = TA + (PD ∙ ΘJA)

TJ = Junction Temperature, [°C ]

TA = Ambient Temperature, [°C ]

PD = Total Chip Power Dissipation, [W]

ΘJA = Package Thermal Resistance, [°C/W]

The total power dissipation can be calculated from:

PD = PINT + PIO

PINT = Chip Internal Power Dissipation, [W]

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