S-19680AAAH-K8T2U Datasheet, PDF (12/27 Pages) Seiko Instruments Inc – Current consumption during operation

FOR AUTOMOTIVE 105°C OPERATION CURRENT MONITOR HIGH SIDE SWITCH
S-19680 Series
Rev.1.1_00
2. 2 Load short-circuit detection circuit
By the load short-circuit detection circuit, the S-19680 Series detects the _{_}s_{_}h_{__}o_{_} rt-circuit status of the load
connected to the OUT pin, and outputs an alarm signal. The output form of the SC pin which outputs the alarm
signal is Nch open-drain output, the output logic is active "L".
The load short-circuit detection circuit monitors I_SHUNT depending on I_SENSE value. When the condition of
I_SHUNT ≥ load short-circuit detection current (I_SHORT) is satisfied, the status changes to the load short-circuit
detection status and the Nch output transistor is turned on. When the condition of I_SHUNT ˂ I_SHORT is satisfied, the
status changes to the load short-circuit release status and the Nch output transistor is turned off.
Caution 1. As a result of the power supply startup and the power supply fluctuation, an inrush current may
flow from the VIN pin to the OUT pin. Even in the load short-circuit release status, when the
condition of I_SHUNT ≥ I_SHORT is satisfied temporarily due to the inrush current, the status changes to
the load short-circuit detection status. Therefore, caution should be exercised.
2. As a result of the power supply fluctuation, the VIN pin voltage may drop lower than the OUT pin
voltage. At this time, no current flows from the VIN pin to the OUT pin. For this reason, even in the
load short-circuit detection status, the condition of I_SHUNT ˂ I_SHORT is satisfied temporarily and the
status changes to the load short-circuit release status. Therefore, caution should be exercised.
2. 3 Load open detection circuit
By the load open detection circuit, the S-19680 Series detects _{_}t_{_}h_{_}e_{__} open status of the load connected to the OUT
pin, and outputs an alarm signal. The output form of the O L pin which outputs the alarm signal is Nch
open-drain output, the output logic is active "L".
The load open detection circuit monitors I_SHUNT depending on I_SENSE value. When the condition of
I_SHUNT ≤ load open detection current (I_OPEN) is satisfied, the status changes to the load open detection status and
the Nch output transistor is turned on. When the condition of I_SHUNT > I_OPEN is satisfied, the status changes to the
load open release status and the Nch output transistor is turned off.
Caution 1. As a result of the power supply startup and the power supply fluctuation, an inrush current may
flow from the VIN pin to the OUT pin. Even in the load open detection status, when the condition
of I_SHUNT > I_OPEN is satisfied temporarily due to the inrush current, the status changes to the load
open release status. Therefore, caution should be exercised.
2. As a result of the power supply fluctuation, the VIN pin voltage may drop lower than the OUT pin
voltage. At this time, no current flows from the VIN pin to the OUT pin. For this reason, even in the
load open release status, the condition of I_SHUNT ≤ I_OPEN is satisfied temporarily and the status
changes to the load open detection status. Therefore, caution should be exercised.
RSHUNT VIN
ISHUNT
*1
OUT
VDD C_IN
VSHUNT
CL
RL
RSENSE ^SENSE
VDD
−+
Current
*1
sense amplifier
ISENSE
I/V
conversion
circuit
Current limit circuit
_____
SC
Load short-circuit
detection circuit
_____
OL
Load open
detection circuit
*1. Parasitic diode
12
Figure 13