Texas Instruments TPS3801, Отчет о приложении

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Applications
20 SLVA075
Reset
Logic
TPS3809J25
_
+
REF
Supply of the IC
R2
R1
100 nF
VDD
GND
R4
22.5 k
Ω
IQ
IDEVICE
R3
12.4 k
Ω
ITOTAL
Vin
RESET
Figure 23. Supervision of 3.6 V With Less Current Consumption
5.4.4 Worst Case Considerations for Application 2
The following assumptions have been made:
Resistors with 1% tolerance are used and a supply current over process and
temperature of 7
µ
A to 13
µ
A.
PARAMETER MINIMUM TYPICAL MAXIMUM
ISupply 7
µ
A 10
µ
A 13
µ
A
RDEVICE 173 k
Ω
225 k
Ω
321 k
Ω
R3 12.28 k
Ω
12.4 k
Ω
12.52 k
Ω
R4 22.37 k
Ω
22.6 k
Ω
22.83 k
Ω
R4equivalent 19.81 k
Ω
20.54 k
Ω
21.31 k
Ω
VIT– 2.20 V 2.25 V 2.30 V
Vtrip 3.47 V 3.60 V 3.76 V
Worst case 1:
V
tripmin
+
R
3 min
)
R
4 equivalent max
R
4 equivalent max
V
IT min
+
12.28 k
W )
21.31 k
W
21.31 k
W
2.20
V
+
3.47
V
Worst case 2:
V
tripmax
+
R
3 max
)
R
4 equivalent min
R
4 equivalent min
V
ITmax
+
12.52 k
W )
19.81 k
W
19.81 k
W
2.30
V
+
3.75
V
RESULT: The adjusted threshold voltage has a tolerance of –3.7% to 4.3%.