BU26154MUV Datasheet, PDF (77/89 Pages) Rohm – High PSRR is attained by built-in regulator

BU26154MUV
Power dissipation
4.00
3.50
3.00
2.50
2.00
1.50
1.00
0.50
0.00
0
20
40
60
80
100 120 140
ambient temperature : Ta(℃)
Datasheet
Figure 49.VQFN040V6060 Package
Measuring instrument: TH-156 (Kuwano Electrical)
Measuring status: PCB mounting(Rohm)
PCB size: 74.2mm × 74.2mm × 1.6mm (PCB with thermal via)
The quarity of the material: FR4
The part of package bottom exposure heat sink connected PCB by solder.
PCB (1): 1-layer board (Size of copper foil on bottom: 23.69mm2), θja = 125.0℃/W
PCB (2): 4-layer board (Size of copper foil on top and bottom: 23.69mm2, 2nd and 3rd layer
Size of copper foil on bottom: 5505mm2), θja = 33.2℃/W
PCB (3): 4-layer board (Size of copper foil on bottom: 5505mm2), θja = 27.4℃/W
Please consider power dissipation by an actual using status, and perform the thermal design which has a margin enough.
Although this product is exposing the frame on the bottom side of a package, heat dissipation processing is performed to
this portion, and we assume raising and using heat dissipation efficiency. Please use not only PCB-top pattern but also
PCB-bottom pattern, taking heat dissipation pattern as large as possible at it.
Although D-class speaker amplifier have very high efficiency compared with the conventional analog-speaker amplifier and
there is also little generation of heat, when continuous action is carried out by the maximum output power, actual power
dissipation may exceed Pd. Please consider the thermal design enough so that power dissipation of averaging output
power does not exceed Pd.
（Tjmax ： Maximum junction temperature=125℃, Ta ：Ambient temperature[℃], θja ：Package thermal registance[℃/W],
Poav：Averaging output power[W], η：Efficiency）
Package Power dissipation Pd （W） = （Tjmax - Ta）/ θja
Circuit Power dissipation Pdiss（W） = Poav * （1 / η- 1）
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TSZ02201-0V1V0R501570-1-2
23.Jun.2014 Rev.001