KKA3354

Functional Description

externally connected. As soon as an internal switching threshold of 7 V is reached, trigger pulses are

delivered at the output TR with a repetition instalment of 960 µs. After successful triggering of the oscillator

circuit, an oscillation detector guarantees blocking of further trigger pulses. It identifies a stable oscillating

process, after a minimum of oscillations is detected per timing.

As soon as a switching threshold of 8 V is reached, all logic units are reset and the timer output S is activated

as well. The IC starts a counter, which interrups the control after one second.

Furthermore, the IC monitors the temperature and the oscillation circuit from a supply voltage of 8 V.

The comparator input EI is useful for error detection. Voltage > 3.75 V, applied at EI, are evaluated as error

signals. The error signal is enqired and registered within a cycle repeating every 960 µs. After registration of

the error signal, a counter starts to generate a delay of one second. After this delay time, the voltage at EI is

evaluated again. The error storage is set only after a second error, appearing within a directly following

evaluation cycle. This error storage is resettable by a short-time power supply disconnection, or with input

LW connected via a change of lamp.

The error storing causes the cutting further triggers and the control of the turn-off transistor as well, which

turns the output TR to ground. Therefore, the turn-off transistor prevents the control of the oscillator circuit,

attenuating it extremly quickly.

Thereby, the current consumption increases by the control of the turn-off transistor. This current amounts

nominal current

feed is less 5 mA). With a switching threshold of 6 V, the control current of the turn-off transistor is

switched off, that enables the supply voltage to rise up to the limiting voltage. Because the trigger pulse gate,

blocked by the error memory, the oscillation can’t start again.

With error storing and attenuation of the oscillation by overtemperature it can be defined via selection of the

temperature mode, whether the oscillation is automatically triggered after cooling-down of the assembly, or

only after mains disconnection.

Absolute Maximum Ratings

Pin

Symbol

min

max

unit

current consumption

20

mA

peak current for t< 100 µs

100

mA

input voltage error indicator

EI

-0.3

V

V

input voltage lamp

exchange input

LW

-0.3

15

voltage difference between

divider factor 16 via LW

LW

CC

6

V

input current at pin TM

TM

1

mA

negative current load

for t<1µs with max. repeat

frequency = 200kHz

TR

-500

mA

switching output current

S

1

mA

junction temperature

150

°C

storage temperature

-50

150

°C

ambient temperature

-20

120

°C

ESD protection

2

kV

2