TDA9535L
9 POWER DISSIPATION
The total power dissipation is the sum of the static
DC and the dynamic dissipation:
PTOT = PSTAT + PDYN.
The static DC power dissipation is approximately:
PSTAT = VDD x IDD + VCC x ICC
The dynamic dissipation is, in the worst case (1
pixel On/ 1 pixel Off pattern):
PDYN = 3 VDD x CL x VOUT(PP) x f x K
where f is the video frequency and K the ratio be-
tween the active line and the total horizontal line
duration.
Example:
for VDD = 110V, VCC = 12V,
IDD =15mA, ICC = 40mA,
VOUT = 40 VPP, f = 40MHz,
CL = 8pF and K = 0.72.
We have:
PSTAT = 2.13W, PDYN = 3.04W
Therefore:
PTOT = 4.41W.
Note 4:
This worst thermal case must only be
considered for TJmax calculation.
Nevertheless, during the average life of the
circuit, the conditions are closer to the white
picture conditions.
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