1 Features

• Qualified for automotive applications

• AEC-Q100 qualified with the following results:

– Device temperature grade 1: –40°C to +125°C

ambient operating temperature range

– Device HBM classification level 2

– Device CDM classification level C4B

• Window-watchdog with programmable delay and

window ratio

• 6-Pin SOT-23 package

• Supply current of 9 μA (Typical)

• Power-on reset generator with a fixed delay time of

25 ms

• Precision supply-voltage monitor (VIT):

2.5 V, 3 V, 3.3 V, 5 V

• Open-drain reset output

2 Applications

• On-board (OBC) and wireless charger

• Driver monitoring

• Digital cockpit processing unit

• ADAS domain controller

• Automotive telematics control unit

3 Description

The TPS3813-Q1 supervisory circuits provide circuit

initialization and timing supervision, primarily for DSPs

and processor-based systems.

During power on, the RESET pin is asserted when

the supply voltage (VDD) becomes higher than 1.1 V.

Thereafter, the supervisory circuit monitors VDD and

keeps the RESET pin active as long as VDD remains

below the threshold voltage (VIT).

An internal timer delays the return of the output to the

inactive (high) state to ensure proper system reset.

The delay time, td = 25 ms typical, begins after VDD

has risen above the threshold voltage (VIT). When

the supply voltage drops below the threshold voltage

(VIT), the output becomes active (low) again. No

external components are required. All the devices of

this family have a fixed-sense threshold voltage (VIT)

set by an internal voltage divider.

For safety-critical applications, the TPS3813-Q1

family of devices incorporate a window-watchdog with

programmable delay and window ratio. The upper

limit of the watchdog time-out can be set by either

connecting the WDT pin to GND or VDD, or by using

an external capacitor. The lower limit, and thus the

window ratio, is set by connecting the WDR pin to

GND or VDD. The RESET pin will assert a reset to the

microcontroller if the watchdog is incorrectly serviced.

The product spectrum is designed for supply voltages

of 2.5 V, 3 V, 3.3 V, and 5 V. The devices are

available in a 6-pin SOT-23 package. The devices are

characterized for operation over a temperature range

of –40°C to 125°C.