Rainbow Electronics BA4900 - Manual (Page 7)

257
Regulator ICs BA4900
F
Estimate of allowable power dissipation.
Except under transitional conditions, the power dissipation of this IC is 3W per unit at 25 _ C.
See Fig.3 for thermal derating characteristics, including some cases where heat sinks are used.
A = maximum output voltage for V
CC
I
1
= maximum output current for V
DD
I
2
= maximum output current for COM
I
3
= maximum output current for AMP
I
4
= maximum output current for ANT
I
5
= maximum output current for RADIO
I
6
= maximum output current for FM
I
7
= maximum output current for VAR
S Power consumed by V
DD
5.8V P
1
= (A * 5.8V) I
1
) (I
1
/ 20 ) I
1
/ 10) A
S
Power consumed by COM 8.0V P
2
= (A
*
8.0V) I
2
)
(I
2
/ 30
)
I
2
/ 10) A
S
Power consumed by AMP P
3
= 1V I
3
)
(22mA) A
S Power consumed by ANT P
4
= 1V I
4
) (22mA) A
S
Power consumed by RADIO 8.0V P
5
= (A
*
8.0V) I
5
)
(I
5
/ 60
)
I
5
/ 10) A
S
Power consumed by FM 8.0V P
6
= (A
*
8.0V) I
6
)
(I
6
/ 60
)
I
6
/ 10) A
S
Power consumed by VAR 10.0V P
8
= (A
*
10.0V) I
7
)
(I
7
/ 10
)
I
7
/ 10) A
S Power consumed internally by each circuit P
7
= V
CC
supply current (about 13mA)
PMax. = P
1
)
P
2
)
P
3
)
P
4
)
P
5
)
P
6
)
P
7
)
P
8
Fig.1