Figure 3-2, Figure 3-3, At different coolings or thermal resistances (r – Rainbow Electronics ATA6626 User Manual
Page 8: Of the external npn transistor t1. figure 3-2. i, Versus v, At r, 80 k/w (no additional cooling) figure 3-3. i, 50 k/w (additional cooling) figure 3-4. i, 20 k/w (additional cooling)
8
4970A–AUTO–01/07
ATA6621/22/24 Development Board
,
and
show the maximum output current (I
max
) of the voltage
regulator as a function of the supply voltage (V
S
) at different coolings or thermal resistances
(R
thJA
) of the external NPN transistor T1.
Figure 3-2.
I
max
versus V
S
at R
thJA
= 80 K/W (No Additional Cooling)
Figure 3-3.
I
max
versus V
S
at R
thJA
= 50 K/W (Additional Cooling)
Figure 3-4.
I
max
versus V
S
at R
thJA
= 20 K/W (Additional Cooling)
0
50
10 0
150
2 0 0
2 50
3 0 0
3 50
10
12
14
16
18
2 0
V
S
(V)
I
max
(mA)
T
a
= 25˚C
T
a
= 85˚C
T
a
= 125˚C
V
S
(V)
I
max
(mA)
0
10 0
2 0 0
3 0 0
4 0 0
50 0
6 0 0
10
12
14
16
18
2 0
T
a
= 25˚C
T
a
= 85˚C
T
a
= 125˚C
V
S
(V)
I
max
(mA)
0
2 0 0
4 0 0
6 0 0
8 0 0
10 0 0
12 0 0
14 0 0
10
12
14
16
18
2 0
T
a
= 125˚C
T
a
= 85˚C
T
a
= 25˚C