TK11900 Datasheet, PDF (7/10 Pages) TOKO, Inc – ADJUSTABLE LOW DROPOUT REGULATOR

TK11900
DEFINITION AND EXPLANATION OF TECHNICAL TERMS (CONT.)
The range of usable currents can also be found from the
graph below.
(mW)
3
PD
DPD
6
4
5
25
50
75
150
TA (°C)
Procedure:
1)
Find P_D
2)
P_D1 is taken to be P_D x (~ 0.8 - 0.9)
3)
Plot P_D1 against 25 °C
4)
Connect P_D1 to the point corresponding to the 150
°C with a straight line.
5)
In design, take a vertical line from the maximum
operating temperature (e.g., 75 °C) to the derating
curve.
6)
Read off the value of P_D against the point at which
the vertical line intersects the derating curve. This
is taken as the maximum power dissipation, D_PD.
The maximum operating current is:
I_OUT = (D_PD / (V_IN(MAX) - V_OUT)
500
400
300
200
100
0
0
MOUNTED
FREE AIR
50
100
150
TA (°C)
SOT-23L POWER DISSIPATION
November 2000 TOKO, Inc.
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