6

Test pulse feature description

The built-in test pulse feature eases diagnostic checks. It is possible to know on a regular basis that the CLT03 is

still working properly.

This feature is especially important for safety applications and often required by safety regulations.

In order, to enable the Test Pulse feature a capacitor should be connected between TP and OUTN pins. When

such a capacitor is connected, the OUTP value will be forced to low state every TP period (PTP) for a define test

pulse width (tTP). TP period is equal to 256 times tTP.

The frequency of the “Test Pulse low state” is managed through the capacitor value. In order to disable this

feature, TP should be shorted to OUTN.

Table 7. Test pulse parameters

Symbol

Description

Min.

Typ.

Max.

Unit

fTP

Test pulse frequency

4.1

219

kHz

CTP

External capacitor range

100

4700

pF

tTP

Test pulse width

1/fTP

ms

PTP

Test pulse period

256 x tTP

ms

ΔfTP

Test pulse frequency variation (out of capacitance variation)

-60

+60

%

Figure 7. Test Pulse parameters description

t

TP

IN

IN

OUT

OUT

P

TP

No test pulse

Test pulse actived

CLT03-2Q3, CLT03-1SC3

Test pulse feature description

DS12302 - Rev 13

page 10/24