ICHAUS IC

iC-OW
INCREMENTAL OPTO ENCODER
Rev A1, Page 1/7
FEATURES
APPLICATIONS
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Monolithically integrated photodiodes
Excellent matching, high reliability
Differential scanning for tracks A and B
Adjustable threshold for index track Z
Gated index Z with switch-off capability
Adjustable LED current control compensates for temperature
and system ageing effects
50mA LED driver integrated
Control monitoring with alarm output
Electronic test aids
Track outputs TTL-compatible and short-circuit-proof
ESD protection
Optical position decoding for
incremental encoders using the
principle of differential scanning
CHIP
A+
B+
B-
A-
Z
chip size 4.02mm x 3.24mm
BLOCK DIAGRAM
+5V
CLR
100nF
+5V
CODE DISC
VCC
A
DPA
DPB
DNB
DNA
OUT_A
TRACK A
LED
B
OUT_B
TRACK B
iC-OW
RETICLE
RLED
68Ω
DZ
Z
OUT_Z
TRACK Z
NERR
TIP
NERR
LEDERROR
TIN
NTEST
TEST
LED-CURRENT CONTROL
CLR
CLR
10nF
© 2001
iC-Haus GmbH
Integrated Circuits
Am Kuemmerling 18, D-55294 Bodenheim
LED
ILR
RLR
15kΩ
IZ
AGND
DRIVER
GND
RZ
15kΩ
Tel +49-6135-9292-0
Fax +49-6135-9292-192
http://www.ichaus.com
iC-OW
INCREMENTAL OPTO ENCODER
Rev A1, Page 2/7
DESCRIPTION
iC-OW is an evaluator iC for optical incremental linear and rotary motion sensors, such as glass scales or
shaft encoders, for example. A photodiode array, amplifiers, comparators and TTL-compatible push-pull
output drivers are integrated monolithically.
Two tracks, A and B, are evaluated differentially, with index track Z as constant light. The integrated LED
current control with a driver stage enables a transmitter LED with a series resistor to be directly connected to
the device and ensures a constant optical receive power. Two external resistors are used to set the
comparator threshold of the relative index track and to determine the receive photocurrents.
The internal logical AND operation of index track Z to tracks A and B can be switched off for adjustment.
A monitoring circuit generates an error message when the LED current control range is violated. The error
output, designed as an open collector, is low active and functions simultaneously as an input which can turn
off the AND operation of the index track.
All pins are protected against destruction by ESD. The outputs are short-circuit-proof.
CHIP LAYOUT
PAD DESCRIPTION
ILR IZ CLR
LED
B+
A+
Name
Function
VCC
A
B
Z
NERR
+5V Supply Voltage
Track A Output
Track B Output
Track Z Output
Error Output (low active) / AND Gate
Disable Input
LED Current Control Output
Capacitor for LED Current Control
Index Track Threshold Adjust
LED Current Control Setup
Ground
Reference Ground for
ILR, IZ, CLR circuitry
NERR
A-
B-
Z
TIP
TIN
NTEST
B
Z
A
VCC
AGND
LED
CLR
IZ
ILR
GND
AGND
GND
TIP
TIN
NTEST
Positive Test Aid Input
Negative Test Aid Input
Test Enable Input, low active
iC-OW
INCREMENTAL OPTO ENCODER
Rev A1, Page 3/7
ABSOLUTE MAXIMUM RATINGS
Values beyond which damage may occur; device operation is not guaranteed.
Item
Symbol
Parameter
Conditions
Fig.
Unit
Min.
Max.
0
6
-0.3
VCC+0.3
V
-4
4
mA
Current in ILR, IZ
-6
1
mA
G005 I(CLR)
Current in CLR
-1
1
mA
G006 I(LED)
Current in LED
V(LED)> VCC
-1
1
mA
G007 I(LED)
Current in LED
V(LED)# VCC
-1
60
mA
-0.3
VCC+0.3
V
-4
4
mA
G001 VCC
Supply Voltage
G002 V(A,B,Z)
Voltage at Outputs A, B, Z
G003 I(A,B,Z)
Current in Outputs A, B, Z
G004 I(ILR)
I(IZ)
V(A,B,Z)< 0V or V(A,B,Z)> VCC
G008 V(NERR) Voltage at NERR
V(NERR)< 0 or V(NERR)> VCC
V
G009 I(NERR)
Current in NERR
TG1 Tj
Operating Junction Temperature
-25
120
°C
TG2 Tj
Storage Temperature Range
-40
150
°C
THERMAL DATA
Operating Conditions: VCC= 5V ±10%
Item
Symbol
Parameter
Conditions
Fig.
Unit
Min.
T1
Ta
Operating Ambient Temperature
Range
(extended range on request)
All voltages are referenced to ground unless otherwise noted.
All currents into the device pins are positive; all currents out of the device pins are negative.
-25
Typ.
Max.
125
°C
iC-OW
INCREMENTAL OPTO ENCODER
Rev A1, Page 4/7
ELECTRICAL CHARACTERISTICS
Operating Conditions: VCC= 5V ±10%, RZ= RLR= 15kS, CLR= 10nF, 8= 850nm, Tj= -25..125°C, unless otherwise noted
Item
Symbol
Parameter
Conditions
Tj
°C
Fig.
Unit
Min.
Typ.
Max.
Total Device
001 VCC
Permissible Supply Voltage
002 I(VCC)
Supply Current in VCC,
Outputs A, B, Z hi
closed LED control loop, I(LED).
3mA, NERR= hi, I(A,B,Z)= 0;
I(DZ,DPx)= -400nA,
I(DNx)= -40..0nA, (x= A,B)
003 I(VCC)
Supply Current in VCC,
Outputs A, B, Z lo
see 002; I(DZ,DPx)= -40..0nA
I(DNx)= -400nA
004 fo
Cut-off Frequency
for Tracks A and B
sinusoidal waveform,
I(DPx)= -20..-400nA,
I(DNx)= -400..-20nA
500
kHz
005 fo
Cut-off Frequency
for Index Track Z
rectangular waveform,
I(DZ)= -20..-400nA
250
kHz
006
)tp()
4.5
27
5.5
V
10
mA
12
mA
mA
5.5
Propagation Delay Deviation
track vs.track at A, B, Z
100
ns
Photodiodes
007 Aph()
Radiant Sensitive Area
008 S(8)max
Spectral Sensitivity
009 Sar(8)
Spectral Application Range
diodes DPA, DNA, DPA, DPB
diode DZ
mm2
mm2
0.95 x 0.74
2.00 x 0.74
0.5
Sar(8)= 0.1 x S(8)max
A/W
500
1050
A/W
Permissible Sensor Current at
DPA, DNA, DPB, DNB
-600
0
nA
102 CM(P/N) Common Mode DPA vs. DNA,
DPB vs. DNB
0.85
1
1.15
15
20
25
%
0
nA
10
13
%
Differential Photocurrent Amplifier, Tracks A and B
101 I(DPx)
I(DNx)
Comparators, Tracks A and B
201 Hys
Hysteresis referred to
[I(DPx) + I(DNx)] / 2
I(DPx,DNx)= -400..0nA
Photocurrent Amplifier, Index Track Z
401 I(DZ)
Permissible Sensor Current at DZ
-600
Comparator, Index Track Z
801 Hys
Hysteresis referred to I(DZ)
I(DZ)= -400..0nA
7
Push-Pull Outputs A, B, Z
301 Vs()hi
Saturation Voltage hi
Vs()hi= VCC -V();
I()= -400µA
-25
27
70
125
0.9
0.8
0.75
0.7
1.1
1.0
0.9
0.9
V
V
V
V
302 Vs()hi
Saturation Voltage hi
Vs()hi= VCC -V();
I()= -1.6mA
-25
27
70
125
1.2
1.1
1.05
1.05
1.5
1.4
1.3
1.3
V
V
V
V
303 Vs()lo
Saturation Voltage lo
I()= 0.8mA
I()= 1.6mA
0.4
0.5
V
V
304 Isc()hi
Short-Circuit Current hi
V()= 0V..2.8V
-8
-1.7
mA
305 Isc()lo
Short-Circuit Current lo
V()= 1V..VCC
2
13
mA
iC-OW
INCREMENTAL OPTO ENCODER
Rev A1, Page 5/7
ELECTRICAL CHARACTERISTICS
Operating Conditions: VCC= 5V ±10%, RZ= RLR= 15kS, CLR= 10nF, 8= 850nm, Tj= -25..125°C, unless otherwise noted
Item
Symbol
Parameter
Conditions
Tj
°C
Fig.
Unit
Min.
Typ.
Max.
Push-Pull Outputs A, B, Z (continued)
306 Vc()hi
Clamp Voltage hi
Vc()hi= V()-VCC; I()= 4mA
0.4
1.5
V
307 Vc()lo
Clamp Voltage lo
I()=-4mA
-1.5
-0.4
V
-1500
-50
nA
0.1
50
mA
0.4
1.2
V
V
LED Current Control: CLR, ILR, IZ, LED
601 ISUM
Permissible Total Photocurrent
602 I(LED)
Permissible Driver Current in LED
603 Vs(LED) Saturation Voltage lo at LED
ISUM= I(DPA)+I(DNA) +I(DPB)
+I(DNB)
I(LED)= 50mA,
I(ILR)> 5µA, ISUM= 0
27
0.8
604 Vref()
Reference Voltage at ILR, IZ
I(ILR,IZ)= -150..-5µA
606 Isc()
Short-Circuit Current in ILR, IZ
V(ILR)= 0, V(IZ)= 0
1.15
-5
1.22
1.28
V
607 CR1()
Current Ratio I(ILR)/ISUM
closed LED control loop,
ISUM= -800..-50nA
80
100
125
608 CR2()
Current Ratio I(IZ)/I(DZ)
closed LED control loop,
I(DZ)= -400..-10nA
320
400
500
609 Vc()hi
Clamp Voltage hi
at LED, CLR, ILR, IZ
VCC= 0V, I()= 1mA
0.4
1.0
V
610 Vc()lo
Clamp Voltage lo
at LED, CLR, ILR, IZ
VCC= 0V, I()= -1mA
-1.0
-0.4
V
45
kS
0.4
1
V
0.4
0.8
V
V
5
30
mA
mA
Error Output / AND Gate Disable Input NERR
501 R()
Internal Pull-Up Resistor
502 Vt()
AND Gate Turn-Off Threshold
Gate disabled if V(NERR)< 0.4V
20
30
701 Vs()lo
Saturation Voltage lo
I(NERR)= 1.6mA
I(NERR)= 5mA
702 Isc()lo
Short-Circuit Current lo
V(NERR)= 2V..VCC
703 Vc()hi
Clamp Voltage hi
Vc()hi= V(NERR)-VCC;
NERR=hi, I(NERR)= 4mA
0.4
1.5
V
704 Vc()lo
Clamp Voltage lo
NERR=lo, I(NERR)=-4mA
-1.5
-0.4
V
Test Aid Inputs TIP, TIN, NTEST
A01 CR1()
Current Ratio
I(TIP) / I(DPA,DPB,DZ)
and I(TIN) / I(DNA,DNB)
NTEST= lo, I()= 5..200µA
300
400
550
A02 CR2()
Current Ratio
I(TIP,TIN) / I(CLR)
NTEST= lo, I()= 5..200µA
1.8
2
2.2
A03 V()on
Test Aid Operation Voltage
at TIP, TIN
NTEST= lo; I()= 5..200µA
1.2
2.6
V
A04 Ipd()
Pull-Down Current at TIP, TIN
V(NTEST) open, V(TIP,TIN)< 1V
50
500
µA
A05 Rpu()
Pull-Up Resistor at NTEST
V(NTEST)= 0..0.4V
A06 V0()
Voltage at NTEST
I(NTEST)= 0
A07 Vt()
Threshold Voltage lo at NTEST
80
210
550
kS
0.35
0.7
1.0
V
0.3
V
iC-OW
INCREMENTAL OPTO ENCODER
Rev A1, Page 6/7
APPLICATIONS INFORMATION
Figure 1 shows the schematic of the electronic system of an incremental rotary encoder. iC-Haus devices iC-OW
and line driver iC-WE are used.
The rotary encoder requires the supply voltages VCC= +5V and VB= +5V to +30V (line driver) and supplies the
conditioned signals of tracks A and B and index track Z at the outputs. It is possible to transmit these signals over
lines of 100m in length directly connected to the device. The system’s upper cut-off frequency is typically 300kHz
for tracks A and B.
Internal monitoring functions are available for the chip temperature of the line driver, for the supply voltages and
for the LED current control. The ERROR port provides an error message signal which can be logically linked to
other, external error signals by a simple connection.
Fig. 1: incremental encoder application circuit
iC-OW
INCREMENTAL OPTO ENCODER
Rev A1, Page 7/7
ORDERING INFORMATION
Type
Package
Order designation
iC-OW
-
iC-OW chip
For information about prices, terms of delivery, options for other case types, etc., please contact:
iC-Haus GmbH
Am Kuemmerling 18
D-55294 Bodenheim
GERMANY
Tel +49-6135-9292-0
Fax +49-6135-9292-192
http://www.ichaus.com
This specification is for a newly developed product. iC-Haus therefore reserves the right to modify data without further notice. Please contact
us to ascertain the current data. The data specified is intended solely for the purpose of product description and is not to be deemed
guaranteed in a legal sense. Any claims for damage against us - regardless of the legal basis - are excluded unless we are guilty of
premeditation or gross negligence.
We do not assume any guarantee that the specified circuits or procedures are free of copyrights of third parties.
Copying - even as an excerpt - is only permitted with the approval of the publisher and precise reference to source.