The information included herein is believed to be

accurate and reliable. However, LSI Computer Systems,

Inc. assumes no responsibilities for inaccuracies, nor for

any infringements of patent rights of others which may

result from its use.

CONDUCTION ANGLE, Ø

BRIGHTNESS LEVEL

No output

Off

45˚

Night Light

70˚

Mood Light

105˚

Medium

158˚

Maximum

NOTE: In the schematic shown in Figure 5, the SYNC Input sig-

nal is delayed in phase with respect to the AC Line by about 7°.

This delay reduces the conduction angle, Ø with respect to the

AC Line by 7° from the values shown above.

7237-041395-2

ø

TRIG

SYNC

FIGURE 2. TRIG OUTPUT CONDUCTION ANGLE, Ø

EXT (Pin 6)

The EXT input is functionally similar to the SENS input with

the exception that a high-level pulse is the active signal. It is

recommended that the EXT input be used instead of the

SENS input when long extension wires are used between the

IC and the sensing circuitry (See Figure 5 and Figure 6) be-

cause the EXT input is less susceptible to “Noise”.

Supply voltage negative terminal.

TRIG (Pin 8)

The TRIG output is a low-level pulse of fixed duration oc-

curring once every half-cycle of the SYNC input. The con-

duction angle, Ø of the output in relation to the SYNC signal

controls the lamp brightness. The 5 levels of brightness cor-

respond to the 5 values of Ø as follows:

SENS

Ø, MODE 0

Ø, MODE 1

Ø, MODE 2

OFF

OFF

OFF

70˚

45˚

OFF

105˚

70˚

158˚

158˚

105˚

OFF

OFF

158˚

158˚

70˚

OFF

FIGURE 3. TRIG OUTPUT CONDUCTION ANGLE, Ø, VS SENS INPUT

158˚