AAT1112 View Datasheet(PDF) - Advanced Analogic Technologies
Part Name
Description
MFG CO.
'AAT1112' PDF : 20 Pages View PDF
SwitchRegTM
PRODUCT DATASHEET
AAT1112
1.5A, 1.4MHz Step-Down Converter
AAT1112 Losses
Total losses can be estimated by calculating the dropout (VIN = VO) losses where the power MOSFET RDS(ON) will be at
the maximum value. All values assume an 85°C ambient temperature and a 120°C junction temperature with the TDFN
50°C/W package.
PLOSS = IO12 · RDS(ON)H = 1.5A2 · 0.16Ω = 0.36W
TJ(MAX) = TAMB + ΘJA · PLOSS = 85°C + (50°C/W) · 360mW = 103°C
The total losses are also investigated at the nominal lithium-ion battery voltage (3.6V). The simplified version of the
RDS(ON) losses assumes that the N-channel and P-channel RDS(ON) are equal.
PTOTAL = IO2 · RDS(ON) + (tsw · FS · IO + IQ) · VIN
= 1.5A2 · 152mΩ + (5ns · 1.2MHz · 1.5A + 50μA) · 3.6V = 375mW
TJ(MAX) = TAMB + ΘJA · PLOSS = 85°C + (50°C/W) · 375mW = 104°C
VOUT (V)
3.3
2.5
1.8
1.5
1.2
1.0
0.8
0.6
Inductance
(μH)
3.3
2.2
1.8
1.8
1.2
1.0
1.0
1.0
Part
Number
CDRH4D28
CDRH4D28
CDRH4D28
CDRH4D28
CDRH4D28
SD3114-1.0
SD3114-1.0
SD3114-1.0
Manufacturer
Sumida
Sumida
Sumida
Sumida
Sumida
Cooper
Cooper
Cooper
Size (mm)
5x5x3
5x5x3
5x5x3
5x5x3
5x5x3
3.1x3.1x1.45
3.1x3.1x1.45
3.1x3.1x1.45
Rated
Current
(A)
1.57
2.04
2.2
2.2
2.56
Table 2: Surface Mount Inductors.
IRMS
(A)
ISAT
(A)
1.67
1.67
1.67
2.07
2.07
2.07
DCR (Ω)
36.4
23.2
20.4
20.4
17.5
0.042
0.042
0.042
Manufacturer
Murata
Murata
Part Number
GRM21BR60J106KE19
GRM21BR60J226ME39
Value
10μF
22μF
Voltage
6.3V
6.3V
Table 3: Surface Mount Capacitors.
Temp. Co.
X5R
X5R
Case
0805
0805
1112.2007.11.1.2
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