U2102B-XFPG3Y ATMEL Corporation, U2102B-XFPG3Y Datasheet - Page 9

• Manufacturer Part Number: U2102B-XFPG3Y
• Description: Multifunction Timer IC
• Manufacturer: ATMEL Corporation

7. Programming
8. Trigger Inputs
4767B–INDCO–10/05
Three operating modes can be programmed with the tri-state input pin 6:
The trigger condition of the timer is determined by the two inputs at pins 7 and 8. A Light Depen-
dent Resistor (LDR) can be connected to pin 7, for example, and an IR sensor to pin 8. Since
both inputs are equal and AND-gated they must both be in the ON state to initiate triggering. In
the operating mode “2-stage reverse phase control”, the output stage can additionally be
switched on and switched off by pin 7 alone and independently of the timer.
The enable input pin 7 is implemented as a comparator with hysteresis. The enable threshold is
approximately 2.5 V. The blocking threshold is switched by the control logic in order to avoid
faults as a result of load switching. This threshold is approximately 2 V in switched off condition
and also during the second current flow angle, , in two-stage reverse phase control mode. Oth-
erwise, the blocking or switch-off threshold is 0.5 V.
The input pin 8 is designed as a window discriminator, its window is set at pin 9. The minimum
window of approximately 250 mV is set with V
mately 1.25 V with V
8 lies within the window set at pin 9.
If a resistor divider with an NTC resistor is connected to pin 9, for example, it is possible to com-
pensate the temperature dependence of the IR sensor, i.e., the range is made independent of
temperature.
Noise suppression for t
which could trigger the circuit. Equally, renewed triggering is prevented for t
load switch-off to avoid any self interference.
• Zero-voltage switch (ZVS) with static output (V
• Reverse phase control with two-stage switch-off (V
• Two-stage reverse phase control with dimming function (V
The reverse phase control is inactive here. The output stage is statically switched on after
triggering by the timer and switched off again after the running down of the time (at the zero
crossing of the supply voltage in each case). This operating mode is not possible in two-wire
systems.
The maximum current flow angle,
Switchover to the phase angle , which can be set arbitrarily at pin 4, takes place after
expiry of 3/4 of the tracking time set at pin 5. The output stage switches off after expiry of the
whole tracking time.
The output stage switches to the maximum current flow angle,
ger condition for both inputs (pins 7, 8) is satisfied. Switchover to the current flow angle, ,
set at pin 4 takes place after expiry of 3/4 of the tracking time set at pin 5. The whole process
is repeated from the beginning if renewed triggering takes place at pin 8. The lamp is
switched-off in the following half-wave of the mains voltage if the trigger condition at pin 7
disappears. In this mode, the output stage is switched-on even if only pin 7 is in the ON
state. The current flow angle is then determined by V
light switch).
9
= V
ON
l
. The window discriminator is in the OFF state when the voltage at pin
= 40 ms guarantees that there are no peak noise signals at the inputs
max
, is set when the timer has enabled the output stage.
9
6
= V
= V
13
6
1
, and the maximum window of approxi-
= V
= V
4
(e.g., house number illumination, twi-
15
Ref
6
= V
):
= V
S
13
):
= GND):
max
, (adjustable) if the trig-
OFF
= 640 ms after
U2102B
9