IC-ME Datasheet, PDF (2/11 Pages) IC-Haus GmbH – DUAL LIGHT-GRID PULSE RECEIVER

iC-ME
DUAL LIGHT-GRID PULSE RECEIVER
preliminary
Rev A1, Page 2/11
DESCRIPTION
The iC-ME device is a dual light chain receiver IC.
Typical applications cover light curtains, light barriers
and electro-sensitive protective equipment in gen-
eral.
Integrated on a single chip the iC-ME contains a
bandpass amplifier with a center frequency of typi-
cally 300 kHz, a differential current output plus con-
trol logic to activate the amplifier and the output. De-
activated, the current consumption is very low and
the current outputs SN and SP are switched to high
impedance (zero current).
The control logic of the two cascaded channels con-
sists of a three-stage shift register each, in which the
first respective two flip-flops are triggered by the lead-
ing edge and the third flip-flop by the trailing edge of
the clock input CLK. This produces an artificial de-
lay in order to avoid race conditions when shifting the
input from channel 0 to channel 1 and via the serial
output to the next device in the chain.
The bandpass amplifier is activated when DIN reads
a logical ‘1’. The current output still remains disabled
(zero current) until the output of the first resp. forth
flip-flop of the Control Logic changes to ‘1’. This acti-
vates the bias for the complete signal path from light
detection to the differential current output. The differ-
ential outputs SP and SN are powered up to an equal
current, as far as the attached photodiode does not
receive any changes in light.
The leading edge of a received light pulse (which pro-
duces an increase of photocurrent), causes the out-
put current at SP to increase and at SN to decrease
by an equal value. The sum of I(SP) + I(SN) is kept
constant. For light curtain applications in which only
one device is activated at a time, the outputs SN and
SP can be attached to a two-wire bus.
The amplifier and output automatically return to
standby after processing the serial input data at DIN,
whith the Control Logic receiving the fourth leading
CLK edge. Therefore, a chain circuitry with multiple
beams can be set up with just a single data bit within
a shift cycle.
The IC contains protective diodes to prevent destruc-
tion by ESD. Control logic input pins feature Schmitt-
trigger characteristics for high noise immunity. All
pins are short-circuit proof.
PACKAGING INFORMATION DFN10 to JEDEC Standard
PIN CONFIGURATION DFN10
1
10
2
9
iC−ME
3
8
...
4
7
yyww
5
6
PIN FUNCTIONS
No. Name Function
1 DIN Data Input
2 VDD +5 V Supply Voltage
3 CLK Clock Input
4 DOUT Data Output
5 SP Pos. Differential Current Output
6 PD1 Photo Diode #1, Input Cathode
7 n.c.
8 SN Neg. Differential Current Output
9 GND Ground
10 PD0 Photo Diode #0, Input Cathode
Orientation of the package label ( iC-ME ... yyww) may vary!