AAT2552_08 Datasheet, PDF (27/31 Pages) Advanced Analogic Technologies – Total Power Solution for Portable Applications

SystemPower^TM
AAT2552 Losses
P_TOTAL
=
I_O2
·
(R_DSON(H)
·
V_O
+ R_DSON(L)
V_IN
·
[V_IN
-V_O])
+ (t_sw · F_S · I_O + I_Q) · V_IN
PRODUCT DATASHEET
AAT2552178
Total Power Solution for Portable Applications
= ^{0.22 · (0.59Ω · 1.8V + 0.42Ω · [4.2V - 1.8V])}
4.2V
+ (5ns · 1.5MHz · 0.2A + 30µA) · 4.2V = 26.14mW
T_J(MAX) = T_AMB + Θ_JA · P_LOSS = 85°C + (50°C/W) · 26.14mW = 86.3°C
2552.2008.02.1.2
www.analogictech.com
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