MC68HC705C9ACB MOTOROLA [Motorola, Inc], MC68HC705C9ACB Datasheet - Page 133

• Manufacturer Part Number: MC68HC705C9ACB
• Description: Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

12.4 Thermal Characteristics
12.5 Power Considerations
MC68HC705C9A — Rev. 4.0
MOTOROLA
The average chip-junction temperature, T
where:
For most applications P
The following is an approximate relationship between P
(neglecting P
Solving equations (1) and (2) for K gives:
where K is a constant pertaining to the particular part. K can be
determined from equation (3) by measuring P
known T
by solving equations (1) and (2) iteratively for any value of T
Thermal resistance plastic dual in-line (PDIP)
Thermal resistance plastic leaded chip carrier
Thermal resistance quad flat pack (QFP)
Thermal resistance plastic shrink DIP (SDIP)
(PLCC)
Freescale Semiconductor, Inc.
For More Information On This Product,
T
T
P
P
P
P
K = P
JA
J
A
D
INT
I
D
/
O
= T
= Ambient temperature, C
= P
= K
A
= Package thermal resistance, junction to ambient, C/W
= Power dissipation on input and output pins (user determined)
. Using this value of K, the values of P
= I
D
A
INT
DD
Go to: www.freescale.com
+ (P
J
Electrical Specifications
):
(T
(T
Characteristic
+ P
A
V
J
D
+ 273 C)
+ 273 C) +
DD
I
/
O
watts (chip internal power)
JA
)
I
/
O
« P
INT
JA
and can be neglected.
(P
D
)
2
J
, in C, can be obtained from:
Symbol
D
D
JA
JA
JA
JA
(at equilibrium) for a
and T
Thermal Characteristics
Electrical Specifications
J
Advance Information
can be obtained
D
Value
and T
60
70
95
60
A
.
J
Unit
C/W
C/W
C/W
C/W
133
(1)
(2)
(3)