AAT1123 Datasheet, PDF (15/18 Pages) Advanced Analogic Technologies – 1MHz Step-Down Converter

AAT1123 Losses
P_TOTAL
=
I_O2
·
(R_DSON(HS)
·
V_O
+ R_DSON(LS)
V_IN
·
[V_IN
-V_O])
+ (t_sw · F · I_O + I_Q) · V_IN
0.4² · (0.725Ω · 1.8V + 0.7Ω · [4.2V - 1.8V])
=
4.2V
+ (5ns · 1.0MHz · 0.4A + 50μA) · 4.2V = 122mW
T_J(MAX) = T_AMB + Θ_JA · P_LOSS = 85°C + (160°C/W) · 122mW = 104.5°C
DATA SHEET
AAT1123
1MHz Step-Down Converter
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [e-mail] • www.skyworksinc.com
201975B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 15, 2013
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