Data Sheet

22

Rev. 1.1, 2015-07-27

TLS820F0

Block Description and Electrical Characteristics

Reset Reaction Time

In case the output voltage of the regulator drops below the output undervoltage lower reset threshold

V

reset output “RO” is set to low, after the delay of the internal reset reaction time

t

is part of the reset reaction time

t

Reset Output “RO”

The reset output “RO” is an open collector output with an integrated pull-up resistor. In case a lower-ohmic “RO”

signal is desired, an external pull-up resistor can be connected to the output “Q”. Since the maximum “RO” sink

current is limited, the minimum value of the optional external resistor “

R

RO” on Page 24.

Reset Output “RO” Low for VQ

≥ 1V

In case of an undervoltage reset condition reset output “RO” is held “low” for

V

is 0 V. This is achieved by supplying the reset circuit from the output capacitor.

Reset Adjust Function

The undervoltage reset switching threshold can be adjusted according to the application’s needs by connecting

an external voltage divider (

R

GND. The reset adjustment range for the TLS820F0ELV50 is given in Reset Threshold Adjustment Range. The

reset adjustment range for the TLS820F0ELV33 is given in Reset Threshold Adjustment Range.

When dimensioning the voltage divider, take into consideration that there will be an additional current constantly

flowing through the resistors.

With a voltage divider connected, the reset switching threshold

V

(neglecting the Reset Adjust Pin Current

I

V

(1)

with

•

V

•

R

•

V