S-19680AAAH-K8T2U Datasheet, PDF (13/27 Pages) Seiko Instruments Inc – Current consumption during operation

Rev.1.1_00
FOR AUTOMOTIVE 105°C OPERATION CURRENT MONITOR HIGH SIDE SWITCH
S-19680 Series
2. 4 Truth-value table of load status
_____
_____
According to the SC pin output and the O L pin output, the S-19680 Series can conf_{_}ir_{_}m_{___} the status o_{_}f_{__}t_{_}h_{_} e load
connected to the OUT pin. Refer to Table 9 for details. Since the output form of the SC pin or the O L pin is
Nch open-drain output, "H" is output by the external pull-up resistor.
_____
SC Pin Output
"L"
"H"
"H"
Table 9
_____
O L Pin Output
"H"
"L"
"H"
Load Status
Load short-circuit status
Load open status
Load normal status
2. 5 Effects caused from shunt resistor (R_SHUNT) and sense resistor (R_SENSE) characteristics
R_SHUNT and R_SENSE variations and temperature characteristics affect the accuracy of I_LIM, I_SHORT and I_OPEN. The
values shown in " Electrical Characteristics" are only considered the variation of the IC. In practice, R_SHUNT
and R_SENSE variations also need to be considered, so caution should be exercised.
The following example is for I_LIM. The same results are obtained similarly in both I_SHORT and I_OPEN.
When R_SHUNT and R_SENSE variations are considered, I_LIM maximum value can be expressed by using formula (1),
and the minimum value by using formula (2).
(1)
I_LIMmax' = I_LIMmax ×
(R_SENSEmax / R_SENSE)
(R_SHUNTmin / R_SHUNT)
(2)
I_LIMmin' = I_LIMmin ×
(R_SENSEmin / R_SENSE)
(R_SHUNTmax / R_SHUNT)
In case of R_SHUNT = 5.1 Ω ± 1% and R_SENSE = 5.1 kΩ ± 1%, I_LIM values are calculated by using formula (3) and
formula (4), and the values have approximately ±2% variation compared to the values shown in
" Electrical Characteristics".
(3)
I_LIMmax' =
I_LIMmax × 1.01
0.99
=
I_LIMmax
×
1.02
(4)
I_LIMmin'
=
I_LIMmin × 0.99
1.01
=
I_LIMmin
×
0.98
Remark R_SHUNTmax, R_SHUNTmin: R_SHUNT variation maximum value and minimum value
R_SENSEmax, R_SENSEmin: R_SENSE variation maximum value and minimum value
I_LIMmax, I_LIMmin: I_LIM maximum value and minimum value which are considered only the IC variation.
I_LIMmax', I_LIMmin': I_LIM maximum value and minimum value which are considered variations of R_SHUNT and R_SENSE.
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