Datasheet

MC78M00, MC78M00A Series
http://onsemi.com
7
DEFINITIONS
Line Regulation – The change in output voltage for a
change in the input voltage. The measurement is made under
conditions of low dissipation or by using pulse techniques
such that the average chip temperature is not significantly
affected.
Load Regulation – The change in output voltage for a
change in load current at constant chip temperature.
Maximum Power Dissipation – The maximum total
device dissipation for which the regulator will operate
within specifications.
Input Bias Current – That part of the input current that
is not delivered to the load.
Output Noise Voltage – The rms AC voltage at the
output, with constant load and no input ripple, measured
over a specified frequency range.
Long Term Stability – Output voltage stability under
accelerated life test conditions with the maximum rated
voltage listed in the devices’ electrical characteristics and
maximum power dissipation.
Figure 2. DPAK Thermal Resistance and Maximum
Power Dissipation versus P.C.B. Copper Length
Figure 3. Worst Case Power Dissipation
versus Ambient Temperature (TO–220)
, POWER DISSIPATION (W)
D
P
θ
JC
= 5°C/W
P
D(max)
= 7.52 W
No Heat Sink
θ
HS
= 20°C/W
θ
HS
= 10°C/W
Infinite Heat
Sink
R , THERMAL RESISTANCE
JAθ
JUNCTION-TO-AIR ( C/W)°
L, LENGTH OF COPPER (mm)
P
D
, MAXIMUM POWER DISSIPATION (W)
R
θ
JA
10
5.0
3.0
2.0
1.0
0.5
0.3
0.2
0.1
40
50
60
70
80
90
100
T
A
, AMBIENT TEMPERATURE (°C)
25 50 75 100 125 150
0 10203025155.0
L
L
Free Air
Mounted
Vertically
2.0 oz. Copper
P
D(max)
for T
A
= 50°C
ÎÎÎÎ
ÎÎÎÎ
ÎÎÎÎ
0
0.4
0.8
1.2
1.6
2.0
2.4
Minimum
Size Pad