Datasheet

Technical Note
43/48
BA4558F,BA4558R F/FV/FVM,BA4560F,BA4560RF/FV/FVM,BA4564RFVBA4580RF/FVM,BA4584FV,
BA4584RF/FV,BA8522RF/FV/FVM,BA15218F,BA14741F,BA15532F,BA4510F/FV,BA2115F/FVM
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2011.08 - Rev.B
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●Derating curve
Power dissipation (total loss) indicates the power that can be consumed by IC at Ta=25℃(normal temperature).IC is heated
when it consumed power, and the temperature of IC ship becomes higher than ambient temperature. The temperature that
can be accepted by IC chip depends on circuit configuration, manufacturing process, and consumable power is limited.
Power dissipation is determined by the temperature allowed in IC chip (maximum junction temperature) and thermal
resistance of package (heat dissipation capability). The maximum junction temperature is typically equal to the maximum
value in the storage temperature range. Heat generated by consumed power of IC radiates from the mold resin or lead frame
of the package. The parameter which indicates this heat dissipation capability (hardness of heat release) is called thermal
resistance, represented by the symbol θj-a[℃/W]. The temperature of IC inside the package can be estimated by this
thermal resistance. Fig.319 (a) shows the model of thermal resistance of the package. Thermal resistance θja, ambient
temperature Ta, junction temperature Tj, and power dissipation Pd can be calculated by the equation below:
θja = (Tj-Ta) / Pd [℃/W] ・・・・・ (Ⅰ)
Derating curve in Fig.319 (b) indicates power that can be consumed by IC with reference to ambient temperature. Power that
can be consumed by IC with reference to ambient temperature. Power that can be consumed by IC begins to attenuate at
certain ambient temperature. This gradient is determined by thermal resistance θja. Thermal resistance θja depends on chip
size, power consumption, package, ambient temperature, package condition, wind velocity, etc even when the same of
package is used. Thermal reduction curve indicates a reference value measured at a specified condition. Fig.320(c), ～, (f)
show a derating curve for an example of BA4558, BA4558R, BA4560, BA4560R, BA4564R, BA4580R, BA4584, BA4584R,
BA8522R, BA15218, BA14741, BA15532, BA4510, BA2115.
(*37) (*38) (*39) (*40) (*41) (*42) (*43) (*44) Unit
6.2 5.5 4.7 7.0 5.3 6.2 5.5 4.9 [mW/℃]
When using the unit above Ta=25[℃], subtract the value above per degree[℃]. Permissible dissipation is the value.
When FR4 glass epoxy board 70[mm]×70[mm]×1.6[mm] (cooper foil area below 3[%]) is mounted.
Fig. 320 Derating curve
0
200
400
600
800
1000
0 25 50 75 100 125
周囲温度 Ta [℃]
容量損失 Pd [mW]
0
200
400
600
800
1000
0 25 50 75 100 125
周囲温度 Ta [℃]
容量損失 Pd [mW]
0
200
400
600
800
1000
0 25 50 75 100 125
周囲温度 Ta [℃]
容量損失 Pd [mW]
0
200
400
600
800
1000
0 25 50 75 100 125
周囲温度 Ta [℃]
容量損失 Pd [mW]
(a) Thermal resistance
(b) Derating curve
Fig. 319 Thermal resistance and derating curve
(c)BA4558R/BA4560R/BA4580R/BA8522R/BA2115 family
(d)BA4564R/BA4584/BA4584R family
(e)BA4558/BA4560/BA15218/BA15532/BA4510 family
(f)BA14741F
550mW (*43)
620mW (*42)
490mW (*44)
870mW (*40)
610mW (*41)
BA4558F
BA4560F
BA15218F
BA4510F
BA15532F
BA4510F
780mW (*37)
690mW (*38)
590mW (*39)
BA4558RF
BA4564RF
BA4580RF
BA8522RF
BA2115F
BA4558RFVM
BA4564RFVM
BA4580RFVM
BA8522RFVM
BA2115FVM
BA4558RFV
BA4564RFV
BA8522RFV
BA4564RFV
BA4584RFV
BA4584RF
BA4584FV
BA14741F
0507510012515025
P1
P2
Pd (max)
LSI
の消費電力
[W]
θ' ja2
θ' ja1
Tj ' (m ax )
θja2 < θja1
周囲温度
Ta [
℃
]
θ ja2
θ ja1
Tj (m ax )
周囲温度
Ta [
℃
]
チップ表面温度
Tj [
℃
]
消費電力 P [W]
θja = ( Tj
ー
Ta ) / Pd [
℃
/W]
Ambient temperature Ta [℃]
Chip surface temperature Tj [℃]
Power dissipation P [W]
Power dissipation of LSI [W]
A
mbient temperature Ta [℃]
Power Dissipation [mW]
Power Dissipation [mW]
A
mbient Temperature Ta [℃]
A
mbient temperature Ta [℃]
A
mbient Temperature Ta [℃]
Power Dissipation [mW]
Power Dissipation [mW]
A
mbient temperature Ta [℃]