Automotive, 125°C Operation, 36 V Input, 200 mA, Built-in Watchdog Timer Circuit Voltage Regulator With Reset Function S-19500/19501 Series

Available Applications
Automotive ICs are categorized according to their application. The following symbols indicate the types of applications for which an IC can be used.
Safety critical components typified by engine, transmission, suspension and ABS, and EV/HEV/PHEV related equipment, etc.
Meter, body, headlamp, ITS, etc.
Accessory, car navigation, car audio system, etc.

The S-19500/19501 Series, developed by using high-withstand voltage CMOS technology, is a low dropout positive voltage regulator with the watchdog timer and the reset function, which has high-withstand voltage. The monitoring time of watchdog timer can be adjusted by an external capacitor. Moreover, a voltage detection circuit which monitors the output voltage is also prepared.

Caution: This product can be used in vehicle equipment and in-vehicle equipment. Before using the product in the purpose, contact to SII is indispensable.


Regulator block

Output voltage
3.0 V to 5.3 V, selectable in 0.1 V step
Input voltage
4.0 V to 36.0 V
Output voltage accuracy
±2.0% (Tj = −40°C to +150°C)
Dropout voltage
120 mV typ. (5.0V output product, Iout = 100mA)
Output current
Possible to output 200 mA (Vin = Vout(s) + 1.0 V)*1
Input and output capacitors
A ceramic capacitor of 2.2µF or more can be used.
Ripple rejection
70 dB typ. (f = 100 Hz)
Built-in overcurrent protection circuit
Limits overcurrent of output transistor.
Built-in thermal shutdown circuit
Detection temperature 170°C typ.

Detector block

Detection voltage
2.6 V to 5.0 V, selectable in 0.1 V step
Detection voltage accuracy
±100 mV (Tj = −40°C to +150°C)
Hysteresis width
0.12 V min.
Release delay time
18 ms typ. (Cdly= 47 nF)
Output form
Nch open-drain output (Built-in pull-up resistor)

Watchdog timer block

Autonomous watchdog operation function
The watchdog timer operates due to detection of load current.
Watchdog activation current is adjustable
1.5 mA typ. (WADJ pin is open)
Product type is selectable
S-19500 Series
(Product with watchdog enable function (Output: WO / RO pin))
S-19501 Series (Product without watchdog enable function
(Output: WO pin and RO pin))
Watchdog trigger time is adjustable
43 ms typ. (Cdly= 47 nF)
Output form
Nch open-drain output (Built-in pull-up resistor)


Current consumption
60 μA typ. (Iout = 0 mA, When the watchdog timer is deactivated.)
75 μA typ. (Iout ≤ 5 mA, When the watchdog timer is activated.)
Operation temperature range
Ta = −40°C to +125°C
Lead-free (Sn 100%), halogen-free
AEC-Q100 qualified*2

*1. Please make sure that the loss of the IC will not exceed the power dissipation when the output current is large.
*2. Contact our sales office for details.


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