BA□□JC5 Series,BA00JC5WT

Technical Note

6/10

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2011.02 - Rev.B

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

Thermal Derating Curve

 TO220FP-3/TO220FP-5/TO220FP-5 (V5）

Fig.17

The characteristics of the IC are greatly influenced by the operating temperature. If the temperature exceeds the maximum

dissipation is within the permissible range in order to prevent instantaneous damage resulting from heat and maintain the

reliability of the IC for long-term operation.

The following method is used to calculate the power consumption Pc (W):

Pc = (Vcc – Vo)

 Io + Vcc  Icca

Power dissipation Pd ≥ Pc

The load current Io is calculated:

Calculation Example:

Vcc = 6.0V and Vo = 5.0V at Ta = 85℃

Refer to the above and implement proper thermal designs so that the IC will not be used under excessive power dissipation

conditions under the entire operating temperature range.

The power consumption Pc of the IC in the event of shorting (i.e. the Vo and GND pins are shorted) can be obtained from the

following equation: Pc = Vcc

 (Icca + Ishort) (Ishort: short current)

0

15

25

20

10

5

25

50

75

125

150

100

0

(1)20.0

(2)2.0

(2) During IC without heat sink operation.

j-a = 62.5 (°C/W)

(1) When using an infinite heat sink.

j-c = 6.25 (°C/W)

ja = 62.5°C/W  −16.0mW/°C

25°C = 2000mW

 85°C = 1040mW

Vcc : Input voltage

Vo

: Output current

: Load current

Icca : Circuit current

Io ≤

Pd − Vcc

 Icca

Vcc − Vo

1.040 − 6.0

 Icca

6.0 − 5.0

Io ≤ 860mA (Icca

 30mA)