TLE 4470

Semiconductor Group

15

1998-11-01

Figure 4

Reset Timing

Reset Switching Threshold

The internally set reset threshold is 4.65 V. When using the TLE 4470 G (P-DSO-20-6)

this threshold can be adjusted to 3.5 V <

V

divider to pin RADJ. If this pin is not needed, it can be left open or even better connected

to GND.

R

Definitions:

V

RT

= Reset threshold

V

ref

= comparator reference voltage, typical 1.35 V

(Reset adjust input current

≈ 50 nA)

The reset output pin is internally connected to the stand-by output Q1 via a 30 k

Ω pull-up

resistor. The reset LOW signal at pin RQ in guaranteed down to an output voltage

V

1 V typical.

AED01542

Thermal

Power-on-Reset

Voltage Dip

Secondary

Overload

at Output

Spike

V

D

V

RO

d

Ι

=

V

d

dt

V

Q

RT

V

<

RR

t

at Input

Undervoltage

Shutdown