ICHAUS IC-LO

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iC-LO
TRIANGULATION SENSOR
Rev A1, Page 1/21
FEATURES
APPLICATIONS
♦ Specially formed line image sensor comprising 129 elements
♦ High ambient light suppression of up to 100 kLux with filter
glass
♦ Dynamic range of 100 dB
♦ 2 antivalent switching outputs
♦ Alarm message output
♦ High switching frequencies
♦ Low latency
♦ Power-down reset output
♦ Write protection for internal registers
♦ Diffuse reflective photoelectric
sensors
PACKAGES
oBGA™ LO1C
BLOCK DIAGRAM
VDD
Near Channel
VREF
VCC
VREF
ON
+
VREF
-
VTHSw
VS
+
Adder
-
VTHSe
AC Transimpedance Amplifier
IF
IN
WARN
KSe
+
Far Channel
VREF
KSw
+
VREF
OF
VREF
+
VTHD
VD
SO
KD
+
+
Programmable Differential Amplifier
-
NSO
Programmable
Comparators
iC-LO
NRES
Signal Processing
and FSM
VDD
Oscillator
VCCL
Power-Down
Reset
2 MHz
Low-SideLED Driver
SPI Interface
LED
Bandgap
Reference
Configurable Photodiode Array
MOSI MISO SCK NCS GND
Copyright © 2012 iC-Haus
GNDA
GNDL
http://www.ichaus.com
iC-LO
TRIANGULATION SENSOR
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Rev A1, Page 2/21
DESCRIPTION
iC-LO is suitable for the assembly of diffuse reflective photoelectric sensors based on the principle of
triangulation. Besides iC-LO, all that is required to
create such a setup is a transmitting LED, a low-cost
microcontroller, and a driver device for the switching
output.
The iC contains a photodiode array, consisting of one
near diode, 127 middle diodes, and one far diode.
The diode photocurrents are segmented on two AC
amplifiers (near and far channel). The AC amplifiers
ensures a very good suppression of low-frequency
interference. The sum and difference are calculated
from the output voltages of the amplifiers; these are
evaluated by comparators. From the comparator signals a programmable filter for the evaluation of multiple measurements generates the switching signal
for the light sensor and also a warning on weak received light. The gain characteristic is dynamically
adjusted to the intensity of the received light and becomes a logarithmic characteristic with very powerful input signals (reflective objects). This results in
a very high dynamic range. The integrated low side
driver can drive an LED directly or control an external
driver by CMOS output.
iC-LO is configured using an SPI interface. The internal registers can be protected against overwriting.
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iC-LO
TRIANGULATION SENSOR
Rev A1, Page 3/21
CONTENTS
PACKAGES
4
ABSOLUTE MAXIMUM RATINGS
5
THERMAL DATA
5
ELECTRICAL CHARACTERISTICS
6
CONFIGURATION PARAMETERS
9
REGISTER MAP
10
MEASURING SEQUENCE
11
LED DRIVER
11
NEAR/FAR CHANNEL PARTITION AND
AMPLIFICATION
12
SAMPLE POINT, DIGITAL SIGNAL
CONDITIONING, AND OUTPUT
CONFIGURATION
Digital filter . . . . . . . . . . . .
Sample point in time . . . . . . .
Switching matrix . . . . . . . . .
Output drivers . . . . . . . . . . .
.
.
.
.
.
.
.
.
.
.
.
.
.
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.
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.
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.
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.
.
.
.
.
.
.
.
14
14
14
15
15
SYSTEM CLOCK
16
STARTUP BEHAVIOR, OPERATING MODES,
AND STATUS REGISTER
Startup behavior and operating modes . . . .
Implemented commands . . . . . . . . . . . .
Status register . . . . . . . . . . . . . . . . .
16
16
16
17
POWER DOWN RESET
17
CONFIGURATION NOTES
17
CHIP REVISION
17
Current/Voltage conversion . . . . . . . . . .
12
Channel partitioning . . . . . . . . . . . . . .
12
Comparator hysteresis . . . . . . . . . . . . .
13
SPI INTERFACE
18
14
APPLICATION NOTES
18
RECEIVED SIGNAL MONITORING
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iC-LO
TRIANGULATION SENSOR
Rev A1, Page 4/21
PACKAGES
PIN CONFIGURATION oBGA™ LO1C
PIN FUNCTIONS
No. Name Function
A1
A3
B1
B3
C1
C3
D1
D3
E1
E3
F1
F3
G1
G2
G3
Physical dimensions see oBGA™ package specification LO1C.
MOSI
NSO
SCK
SO
MISO
WARN
NCS
NRES
GNDA
VDD
VCC
GND
VCCL
LED
GNDL
Master Output Slave Input
Antivalent Switching Output
SPI Clock
Switching Output
Master Input Slave Output
Warning Output
SPI Chip Select
Power-Down Reset
Analogue Ground
Digital Supply
Analogue Supply
Digital Ground
LED Driver Supply
LED Driver Output
LED Driver Ground
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iC-LO
TRIANGULATION SENSOR
Rev A1, Page 5/21
ABSOLUTE MAXIMUM RATINGS
Beyond these values damage may occur; device operation is not guaranteed.
Item
No.
Symbol
Parameter
Conditions
Unit
Min.
Max.
G001 V()
Supply Voltage at VCC, VDD
-0.3
6
V
G002 V()
Voltage at digital inputs MOSI, SCK,
NCS
-0.3
VDD +
0.3
V
G003 I()
Current in WARN, NSO, SO, MISO,
MOSI, SCK, NCS, NRES, GND
-40
40
mA
G004 I()
Current in VCC, GNDA
-50
50
mA
G005 I()
Current in VDD
-40
70
mA
G006 I()
Current in VCCL
-70
40
mA
G007 I()
Current in LED
-40
1600
mA
G008 I()
Current in GNDL
-1600
40
mA
G009 Tj
Chip-Temperature
-40
125
°C
G010 Ts
Storage Temperature Range
see package specification
G011 Vd()
ESD Susceptibility at all pins
HBM 100 pF discharged through 1.5 kΩ
2
kV
THERMAL DATA
Operating Conditions: VDDA = VDD = 5 V ±10%
Item
No.
T01
Symbol
Parameter
Conditions
Unit
Min.
Ta
Operating Ambient Temperature Range see package specification
All voltages are referenced to Pin GNDA unless otherwise stated.
All currents flowing into the device pins are positive; all currents flowing out of the device pins are negative.
-40
Typ.
Max.
85
°C
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iC-LO
TRIANGULATION SENSOR
Rev A1, Page 6/21
ELECTRICAL CHARACTERISTICS
Operating Conditions: VCC = VDD = 5 V±10 %, Tj = -40. . . 85 °C, fOSC = 2 MHz, unless otherwise stated.
Item
No.
Symbol
Parameter
Conditions
Unit
Min.
Typ.
Max.
4.5
5
5.5
4.5
5
5.5
Total Device
001
V(VCC)
Permissible supply voltage analog
002
V(VDD)
Permissible supply voltage digital
003
I(VCC)
Supply Current in VCC
Iph() = 0
004
I(VDD)
Supply Current in VDD
I(VCCL) = 0
005
Vc()hi
Clamp Voltage hi at NCS, CLK,
VZAP
Vc()hi = V() − V(VDD), I() = 1 mA
0.3
1.6
V
006
Vc()hi
Clamp Voltage hi at VCCL
Vc()hi = V() − V(VDD), I() = 1 mA
0.3
1.6
V
007
Vc()hi
Clamp Voltage hi at LED, GND
Vc()hi = V() − V(VDD), I() = 1 mA
0.3
1.2
V
008
Vc()hi
Clamp Voltage hi at NRES
Vc()hi = V() − V(VDD), I() = 1 mA
0.6
2.6
V
009
Vc()hi
Clamp Voltage hi at WARN, SO,
NSO, MISO
Vc()hi = V() − V(VDD), I() = 1 mA
0.3
1.6
V
010
Vc()lo
Clamp Voltage lo at MOSI, SCK, I() = -1 mA
MISO, NCS, GND, VDD, NRES,
WARN, SO, NSO
-1.2
-0.3
V
011
Vc()lo
Clamp Voltage lo at VCC, VCCL, I() = -1.3 mA
LED, GNDL
-1.2
-0.3
V
4
V
V
mA
0.8
mA
Fotodioden (D0..D128) with cascode
101
L()
Overall length of diode array
7
mm
102
A(D0)
Active area near-diode
3000 µm x (300...600) µm
0.927
mm²
103
A()
Active area mid-diodes D1 to
D127
29.35 µm x 600 µm
17610
µm²
104
A(D128)
Active area far-diode
272.55 µm x 600 µm
163530
µm²
105
S(λ)max
Efficiency
λ = 680 nm
0.38
A/W
106
λar
Spectral Application Range
S(λar) = 0.25 x S(λ)max
107
Imax (D0)
Maximum photocurrent neardiode
8
mA
108
Imax ()
Maximum photocurrent middiodes D1 to D127
750
µA
109
Imax (D128) Maximum photocurrent far-diode
7.5
mA
400
950
nm
AC Transimpedance Amplifier
201
Iph()dc
DC Photocurrent
260
µA
202
203
Iph()ac
AC Photocurrent
12
mA
Iph()lin
Linear Transimpedance range
204
Rac
Transimpedance
-3 dB corner of Rac , Iph()lin = 0...Iph()ac;
TIM = 0x0
TIM = 0x1
TIM = 0x2
TIM = 0x3
10
82
1280
20000
µA
µA
µA
µA
linear range, Iph()ac < Iph()lin;
TIM = 0x0
TIM = 0x1
TIM = 0x2
TIM = 0x3
112.5 k
17.5 k
1350
101
Ω
Ω
Ω
Ω
-19
dB
206
deltaRac
Transimpedance change in loga- deltaRac per decade Iph()ac
rithmic range
208
fu
Lower Cut-off Frequency
linear range, Iph()ac < Iph()lin, -3 dB corner
25
kHz
209
fo
Upper Cut-off Frequency
linear range, Iph()ac < Iph()lin, -3dB corner
200
kHz
301
Avsum
Gain
302
fo
Upper Cut-off Frequency
Adder
1.8
-3 dB corner
2
230
2.2
kHz
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iC-LO
TRIANGULATION SENSOR
Rev A1, Page 7/21
ELECTRICAL CHARACTERISTICS
Operating Conditions: VCC = VDD = 5 V±10 %, Tj = -40. . . 85 °C, fOSC = 2 MHz, unless otherwise stated.
Item
No.
Symbol
Parameter
Conditions
Unit
Min.
Programmable Differential Amplifier (x = F, N)
401 Avn
Near-Channel Gain
Typ.
POTx = 0x00
POTx = 0xFF
8.5
26
402
Avf
Far-Channel Gain
POTx = 0x00
POTx = 0xFF
26
8.5
403
fo
Upper Cut-off Frequency
-3 dB corner
150
Max.
kHz
Programmable Comparator
501
502
503
Voff
Offset
save by design
Vhys (KD)
Hysteresis KD
DISHYS = 0;
HYSD = 0x0
HYSD = 0xF
3
72
mV
mV
DISHYS = 0;
HYSS = 0x0
HYSS = 0x3
2
8
mV
mV
Vhys (KS)
Hysteresis KSw, KSe
-2
2
mV
504
VTHSw
Threshold Voltage for warning
THSw = 0x00
THSw = 0x1F
2.8
89.6
mV
mV
505
VTHSe
Threshold Voltage for error
THSe = 0x00
THSe = 0x1F
2.8
89.6
mV
mV
506
fu
Cut-off Frequency High-pass
Input
-3 dB corner
12
kHz
Oscillator Frequency
OSC = 0x8
2
MHz
Oscillator
701
fOSC
SPI Interface NCS, SCK, MOSI, MISO
I01
Vt()hi
Threshold Voltage hi at NCS,
SCK, MOSI
2
I02
Vt()lo
Threshold Voltage lo at NCS,
SCK, MOSI
I03
Vt()hys
Hysteresis at NCS, SCK, MOSI
I04
Ipu(NCS)
Pull-Up Current in NCS
V(NCS) = 0...VDD − 1 V
I05
Ipd()
Pull-Down Current in SCK and
MOSI
V(SCK) = 1 V...VDD
I06
Vs(MISO)hi Saturation Voltage hi at MISO
Vs(MISO)hi = VDD − V(MISO);
I(MISO) = -1.6 mA
I07
Vs(MISO)lo Saturation Voltage lo at MISO
I(MISO) = 1.6 mA
I08
Isc()hi
Short-Circuit Current hi in MISO
-35
I09
Isc()lo
Short-Circuit Current lo in MISO
1.7
35
mA
I10
f(SCK)
Clock Frequency at SCK
1
MHz
0.8
V
V
450
mV
-70
50
-30
-5
µA
3
30
80
µA
350
mV
300
mV
-1.7
mA
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iC-LO
TRIANGULATION SENSOR
Rev A1, Page 8/21
ELECTRICAL CHARACTERISTICS
Operating Conditions: VCC = VDD = 5 V±10 %, Tj = -40. . . 85 °C, fOSC = 2 MHz, unless otherwise stated.
Item
No.
Symbol
Parameter
Conditions
Unit
Min.
Typ.
Max.
Low-Side LED driver VCCL, GNDL, LED
L01
I(VCCL)
Short-Circuit Current from VCCL V(VCCL) = V(GNDA)
L02
Vs()hi
Saturation Voltage hi at VCCL
L03
I(LED)nom Nominal Current in LED
-55
Vs(VCCL)hi = V(VDD) − V(VCCL);
I(VCCL) = -35 mA
LCC = 0x0
LCC = 0x7
LCC = 0x8
LCC = 0xF
starting with LOY:
LCC = 0x00
LCC = 0x07
LCC = 0x08
LCC = 0x0F
LCC = 0x10
LCC = 0x17
LCC = 0x18
LCC = 0x1F
L04
C
L05
Vs(LED)lo Saturation Voltage lo at LED
Backup Capacitor for LED driver between VCCL and GNDL
Vs(LED)lo = V(LED) − V(GNDL);
LCO = 0x0 (LED-driver mode),
I(LED) = I(LED)nom
L06
Vs(LED)hi Saturation Voltage hi at LED
L07
-39
mA
0.85
V
86
180
420
825
mA
mA
mA
mA
86
180
155
320
295
636
593
1150
mA
mA
mA
mA
mA
mA
mA
mA
10
µF
2
V
Vs(LED)hi = VDD − V(LED);
LCO = 0x1 (CMOS-Output),
I(LED) = -1.6 mA
350
mV
Vs(LED)lo Saturation Voltage lo at LED
LCO = 0x1 (CMOS-Output),
I(LED) = 1.6 mA
300
mV
L08
Isc()hi
Short-Circuit Current hi at LED
LCO = 0x1 (CMOS-Output)
-35
-1.7
mA
L09
L10
Isc()lo
Short-Circuit Current lo at LED
LCO = 0x1 (CMOS-Output)
1.7
fPER
Pulse Frequency
PER = 0x1
PER = 0x3
13.9
5
kHz
kHz
L11
tPW
Pulse Width
PW = 0x0
PW = 0xF
2
9.5
µs
µs
35
mA
Digital Outputs SO, NSO, WARN, NRES
O01 Vs()hi
Saturation Voltage hi at SO,
NSO, WARN, NRES
Vs()hi = VDD − V();
I() = -1.6 mA
350
mV
O02 Vs()lo
Saturation Voltage lo at SO,
NSO, WARN, NRES
I() = 1.6 mA
300
mV
O03 Isc()hi
Short circuit current hi at SO,
NSO, WARN, NRES
-35
-1.7
mA
O04 Isc()lo
Short circuit current lo at SO,
NSO, WARN, NRES
1.7
35
mA
3.9
V
Power-Down Reset NRES
R01 Vt(VCC)hi Turn-on Threshold VCC
R02 Vt(VCC)lo Turn-off Threshold VCC
3.0
R03 Hys(VCC) Hysteresis VCC
R04 td
Delay at NRES
VCC switched on
V
150
400
mV
20
40
ms
iC-LO
TRIANGULATION SENSOR
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Rev A1, Page 9/21
CONFIGURATION PARAMETERS
Thresholds
TIM:
Transimpedance (S. 12)
THSW:
Warning Threshold weak received light
(S. 14)
THSE:
Error Threshold weak received light
(S. 14)
HYSD:
Comparator hysteresis difference
(S. 13)
HYSS:
Comparator hysteresis sum (S. 13)
DISHYS:
Disable Comparator hysteresis (S. 13)
Parameter set OBF = ”Object far”
SPF:
Diode segmentation (S. 13)
POTF:
Digital potentiometer (S. 13)
Parameter set OBN = ”Objekt near”
SPN:
Diode segmentation (S. 13)
POTN:
Digital potentiometer (S. 13)
LED Driver
LCO:
LCC:
PW:
PER:
LED driver mode (S. 11)
LED pulse current (S. 11)
Pulse width (S. 12)
Pulse frequency (S. 11)
Digital Filter
FIN:
Number of averaged measurements
(S. 14)
FIM:
Number of complementary
measurements (S. 14)
SKO:
Sample point in time (S. 15)
Internernal Oscillator
OSC:
Frequency trimming (S. 16)
Output Configuration
SOCNO:
Output mode (S. 15)
SOEN:
Output enable (S. 15)
TAR:
Turn-on delay (S. 16)
TAF:
Minimum on-time (S. 16)
Opcode/Status Register
KD:
Last comparator results (S. 17)
TII:
Last transimpedance value (S. 17)
WARNI:
Last output status / warning (S. 17)
SOI:
Last output (S. 17)
OP:
Operating modes (S. 16)
Device Designator
REV:
Revision (S. 17)
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iC-LO
TRIANGULATION SENSOR
Rev A1, Page 10/21
REGISTER MAP
OVERVIEW
Adr
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
THRESHOLDS
SPF(6:0)
POTF(7:0)
SPN(6:0)
POTN(7:0)
0x00
0x01
0x02
0x03
TIM(2:0)
HYSS(1:0)
0x04
0x05
DISHYS
0x06
HYSD(3:0)
THSW(4:0)
THSE(4:0)
LED DRIVER
LCO
0x07
LCC(3:0)
starting with iC-LO Revision Y:
LCO
0x07
LCC(4:0)
PER(1:0)
0x08
PW(3:0)
DIGITAL FILTERING
FIM(3:0)
SKO(3:0)
0x09
0x0A
FIN(3:0)
TAR(1:0)
TAF(1:0)
OSCILLATOR
0x0B
OSC(3:0)
0
OUTPUT CONFIGURATION
0x0C
SOEN
SOCNO
0x0D
INSTRUCTION REGISTER
OP(7:0)
0x0E
STATUS REGISTER (read only)
0x0F
SOI
WARNI
TII(1:0)
KD(3:0)
DEVICE DESIGNATOR (ROM)
0x10
0x11
0x12
0x13
0x14
0x4C =ˆ ’L’
0x4F =ˆ ’O’
REV(7:0)
0x69 =ˆ ’i’
0x43 =ˆ ’C’
Table 4: Register layout
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iC-LO
TRIANGULATION SENSOR
Rev A1, Page 11/21
MEASURING SEQUENCE
In order to determine whether the distance between
an object and the sensor falls below a defined value,
iC-LO initiates a light pulse that is then diffuse reflected
and pictured onto the photodiode array. The spot of
light diffuse reflected by the object moves along the
diode array depending on the distance object to sen-
sor. After the light pulse has been transmitted, at a
defined point in time the signal from the photodiode array is evaluated and decided whether the distance between the object and sensor has fallen below a defined
value or not.
LED DRIVER
iC-LO can drive a transmitting LED directly or trigger
an external driver using the CMOS level output. A lowside driver is integrated to drive the LED and can supply diode currents of up to approx. 1 A with an external
back-up capacitor.
The type of output at pin LED (lowside driver or CMOS
output) is set by parameter LCO.
LCO
Code
Addr. 0x07; bit 4
Description
0x0
CMOS output at pin LED
0x1
Low-side driver at pin LED
RW
Table 5: Configuration LED output type
Starting with chip version iC-LO revision Y the following applies:
LCO
Code
Addr. 0x07; bit 5
Description
0x0
CMOS output at pin LED
0x1
Low-side driver at pin LED
RW
Starting with chip version iC-LO revision Y the following applies:
LCC
Code
Addr. 0x07; bit 4:0
Description
0x0
0x1
...
0x7
0x8
112 mA
126 mA
0x9
...
0xF
0x10
0x11
...
221 mA
0x17
0x18
0x19
...
0x1F
753 mA
696 mA
796 mA
RW
210 mA
193 mA
389 mA
368 mA
423 mA
1396 mA
Table 8: Current in LED (low-side driver)
Table 6: Configuration LED output type
The parameter LCC configures the LED current.
LCC
Code
Addr. 0x07; bit 3:0
Description
0x0
94 mA
0x1
...
0x7
0x8
0x9
...
110 mA
0xF
1030 mA
206 mA
470 mA
550 mA
Table 7: Current in LED (low-side driver)
RW
The frequency of the light pulses in multiple measurement mode (see Table 18) and the duration of a light
pulse is set by parameters PER and PW.
PER
Code
Addr. 0x08; bit 5:4
Description
0x0
0x1
0x2
reserved
13.9 kHz
10.4 kHz
0x3
5 kHz
Table 9: Pulse Frequency
RW
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iC-LO
TRIANGULATION SENSOR
Rev A1, Page 12/21
PW
Code
Addr. 0x08; bit 3:0
Description
0x0
0x1
...
0xF
2 µs
2.5 µs
RW
I(LCC)
t(PW)
1/freq(PER)
9.5 µs
Figure 1: Light pulse
Table 10: Pulse Width
The effect of the individual parameters is shown in Figure 1.
NEAR/FAR CHANNEL PARTITION AND AMPLIFICATION
Sensitivity [A/W]
The typical spectral sensitivity is shown in Figure 2.
Wave Length [nm ]
Figure 2: Spectral sensitivity of the photodiode
The diode array is partitioned into two channels (one
near and one far channel). The channelwise received
photocurrents are added, converted to voltages and
amplified. Afterwards a differential comparator decides
whether the signal of the near or far channel is greater.
A greater signal in the near channel indicates an object
within the defined near range and the switching output
is activated.
Current/Voltage conversion
The transimpedance of the current/voltage conversion
can be configured according to the expected photocurrents. In the static transimpedance setting modes
this configuration is not altered by iC-LO. If the transimpedance amplifier exceeds a high set point it continues with a logarithmic characteristic. In the logarithmic range the parametrized switching point can
shift if the digital potentiometer is used (Table 13).
iC-LO thus has an automatic mode which selects
the transimpedance depending on the received sum
light current. The transimpedance set in the automatic modes represents the start value in operating
mode STARTUP/RESET. Two comparators monitor
the sum light current and switch up or down one transimpedance step when the fixed thresholds are either overshot or undershot. If the transimpedance
setting is to be changed during operation, after programming the device must be reset (operating mode
STARTUP/RESET).
TIM
Code
Mode
Addr. 0x04; bit 7:5
Transimpedance
0x0
0x1
0x2
0x3
0x4
0x5
static
static
static
static
auto
auto
50 kΩ
7765 Ω
600 Ω
45 Ω
50 kΩ
7765 Ω
0x6
0x7
auto
auto
600 Ω
45 Ω
RW
Table 11: Transimpedance Mode
Channel partitioning
The block diagram on page 1 depicts the signal chain.
There are two ways in which the differential comparator input signals and thus the necessary sensing distance can be configured in iC-LO. The two setting
parameters are implemented in two sets of parameters twice. One of these sets of parameters is active
when the switching state is off - i.e. the object was in
the far range during the last measurement (parameter
set OBF). The other is used in switching state on (parameter set OBN). Depending on the difference of the
switching points of the two sets of parameters, a freely
selectable switching hysteresis can be set.
Setting parameters for the near/far channel Diodes
are partitioned to the near and far channels using parameters SPF and SPN. SPF belongs to parameter set
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TRIANGULATION SENSOR
Rev A1, Page 13/21
OBF and SPN to parameter set OBN. Diodes from 0
(near diode) to the set value are assigned to the near
channel, with the remaining diodes up to diode 128 (far
diode) assigned to the far channel.
SPF
SPN
Addr. 0x00; bit 6:0
Addr. 0x02; bit 6:0
Code
Description
0x0
0
0x1
...
0x7F
1
RW
RW
127
Table 12: Diode Assignment
Setting parameter gain ratio In the subtractor the
gain ratio between the near and far channel can be
adjusted using a digital potentiometer. This achieves
a higher measurement resolution than only partitioning the diode array. Parameters POTF (parameter set
OBF) and POTN (parameter set OBN) configure the
potentiometer.
POTF
POTN
Addr. 0x01; bit 7:0
Addr. 0x03; bit 7:0
Code
Gain Ratio Near/Far Channel
0x00
0x01
0.327
0.330
...
0x7E
0x7F
0x80
0x81
...
0.988
0.996
1.004
1.012
0xFE
0xFF
3.026
3.059
teresis of the three comparators KD(compatator difference signal), KSw(comparator warning threshold), and
KSe(comparator error threshold) can be configured.
The system hysteresis is switched with the sampled
and filtered comparator output signals KDF, KSwF, and
KSeF. Parameter HYSD is used to set the hysteresis of
differential comparator KD and parameter HYSS that
of sum comparators KSw and KSe.
HYSD
Code
Addr. 0x04; bit 3:0
Hysteresis KD
0x0
0x1
0x2
0x3
0x4
3 mV
6 mV
9 mV
12 mV
15 mV
0x5
0x6
0x7
0x8
..
0xF
18 mV
21 mV
24 mV
30 mV
RW
72 mV
Table 14: Comparator Hysteresis
RW
RW
HYSS
Code
Addr. 0x05; bit 7:6
Hysteresis KSw, KSe
0x0
0x1
0x2
0x3
2 mV
4 mV
6 mV
8 mV
RW
Table 15: Comparator Hysteresis
The hysteresis can be deactivated by DISHYS.
Table 13: Digital Potentiometer
A gain ratio of > 1 shifts the switching point towards
shorter distances and vice versa.
Comparator hysteresis
To stabilize the comparator outputs the system hys-
DISHYS
Code
Addr. 0x04; bit 4
Description
0x0
0x1
Hysteresis set by HYS
Hysteresis deactivated
Table 16: Hysteresis Deactivation
RW
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RECEIVED SIGNAL MONITORING
Two sum comparators have been integrated to monitor the system and evaluate the intensity of the received light pulse. A switching threshold can be configured separately for each of the comparators. The
warning threshold is configured by using VTHSW and
an error threshold by using VTHSE. If the received
light pulse undershoots the relevant set threshold, the
corresponding comparator output (KSw and KSe, see
block diagram) is set to low. It makes sense to set
the warning threshold higher than the error threshold.
The warning threshold could indicate that the sensor
is contaminated. If the intensity of the received light
pulse undershoots the error threshold, the switching
output is deactivated as a decision cannot be safely
made (see Table 21).
THSW
Addr. 0x05; bit 4:0
RW
THSE
Code
Addr. 0x06; bit 4:0
Description
RW
0x00
VTHSx = 2.8 mV
0x01
..
0x1F
VTHSx = 5.6 mV
VTHSx = 89.6 mV
Table 17: Thresholds Sum Comparators, x = W, E
SAMPLE POINT, DIGITAL SIGNAL CONDITIONING, AND OUTPUT CONFIGURATION
The signal conditioning chain between the comparator
outputs and the switching outputs is shown in Figure 3.
FIN
Description
0x0
0x1
1
2
0x2
...
0xF
3
Update
switching
output
Single measurement
RW
16
Table 18: Number of measurements per cycle
Figure 3: Digital processing and signal output
Digital filter
To improve noise immunity a measurement cycle (see
Figure 4), which results in an update of the switching
and warning outputs, can consist of several individual
measurements (see Figure 5). The number of individual measurements in a measurement cycle is set using
FIN. After each individual measurement the last individual measurements set through FIN are collated to
form a measurement cycle and evaluated.
Addr. 0x09; bit 3:0
Code
FIM
Code
Addr. 0x09; bit 7:4
Description
0x0
0x1
0x2
...
0xF
1
2
3
RW
16
Table 19: Number of measurements complementary
to current comparator state
Measurement cycle consisting of FIN-single measurements
Figure 4: Measurement cycle
In doing so, each comparator output (KD, KSw, and
KSe) is separately filtered. There must then be a minimum number of individual measurements complementary to the current filtered comparator output (KDF,
KSwF, and KSeF) so that the corresponding filtered
comparator output changes its state. This number is
configured using FIM.
Sample point in time
The point in time at which the outputs of the three comparators are sampled during an individual measurement (tsample , see Figure 5) can be shifted using parameter SKO. This shift is always referenced to the rising edge of the light pulse generated in the LED driver.
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Switching matrix
Internal switching state SOI and warning state WARNI
are determined from the filtered comparator outputs
according to the following truth table (Table 21):
Light pulse
tsample
t(SKO)
Single measurement
Figure 5: Single measurement
SKO
Code
Addr. 0x0A; bit 7:4
Description
0x0
0x1
...
1.5 µs
2 µs
0xF
9 µs
RW
Table 20: Shifting the sample point in time
KDF
0
0
0
0
1
1
1
1
KSwF
1
0
0
1
1
0
0
1
KSeF
1
1
0
0
1
1
0
0
SOI
0
0
0
0
1
1
0
0
WARNI
0
0
0
0
0
1
0
0
System state
Object detected far, enough light
Object detected far, low light
Object detection impossible, not enough light
Invalid configuration (see page 14)
Object detected near, enough light
Object detected near, low light
Object detection impossible, not enough light
Invalid configuration (see page 14)
Table 21: Switching matrix
Output drivers
The polarity of the switching output can be selected
due to the connected switch using SOCNO. Output
WARN is equivalent to the internal WARNI signal.
SOCNO
Code
Addr. 0x0C; bit 0
Description
0
Configures the output SO as normally open and
NSO as normally closed (SO = SOI)
Configures the output SO as normally closed and
NSO as normally open (SO = SOI)
1
Furthermore, in mode PERIODIC_MEASURE (Table
27) a rise and fall delay can be configured for the warning and switching outputs (see Figure 6 by way of example).
RW
SOI
t < tAR
t = tAR
t = tAF
t = tAR
t = tAF
SO
Table 22: Output configuration
Figure 6: Rise and fall delay
If the switching outputs SO and NSO are not required,
they can be disabled by SOEN. A zero is then output
at both outputs.
SOEN
Code
Addr. 0x0C; bit 4
Description
0
SO and NSO disabled
1
SO and NSO enabled
Table 23: Output activation
RW
Rise delay tAR suppresses peaks that are shorter than
tAR (first SOI peak in Figure 6). If SOI is active for
longer than tAR , switching output SO is activated. If
SOI then drops to 0, SO only switches back when fall
delay time tAF has elapsed (second SOI peak in Figure 6). If SOI remains at 1 after the fall delay time
has elapsed, SO trails the falling edge at SOI directly
(third SOI peak in Figure 6). The fall delay time is thus
equivalent to a minimum pulse duration at the outputs.
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Warning output WARN can only be switched on at the
same time as the switching output and is reset as soon
as sufficient received light is detected.
The delay times are configured using parameters TAR
and TAF.
TAR
Addr. 0x0A; bit 3:2
Code
Description
0x0
0x1
0 ms
5 ms
0x2
0x3
20 ms
50 ms
TAF
Code
Addr. 0x0A; bit 1:0
Description
0x0
0x1
0x2
0x3
0 ms
5 ms
20 ms
50 ms
RW
Table 25: Fall delay
RW
Table 24: Rise delay
SYSTEM CLOCK
The frequency of the internal oscillator must be
trimmed to ensure correct timing. For this purpose
the system clock can be output at pin WARN using the
command OSC_OUT_ON (Table 27).
OSC
Addr. 0x0B; bit 3:0
Code
Description
0x0
0x1
-20%
-17.5%
...
0x8
...
0xF
RW
0%
17.5%
Table 26: System clock setting
STARTUP BEHAVIOR, OPERATING MODES, AND STATUS REGISTER
Startup behavior and operating modes
After iC-LO has started up all internal registers and
counters are reset to 0. Switching outputs SO and
NSO are thus at 0. The warning output is activated.
The device waits for further commands (operating
mode STARTUP/RESET).
Implemented commands
By writing to address 0x0E commands can be executed and the device operating mode changed.
OP
Code
Addr. 0x0E; bit 7:0
Command
Description
W
0x00
STARTUP/RESET
Operating mode after
power-down (reset of
digital filters)
0x02
SINGLE_MEASURE
0x03
PERIODIC_MEASURE
Single measurement
cycle started with rising
NCS edge
Periodic measurement
cycles, paused with
NCS = ’0’ (normal
operation mode)
0x04
OSC_OUT_ON
0x06
REG_PROT_ON
0x07
REG_PROT_OFF
0x08
0x09
0x0A
0x0B
TST_SO_ON
TST_SO_OFF
TST_WARN_ON
TST_WARN_OFF
...0xFF
reserved for device test
Output 1 MHz clock at
pin WARN
Disable write access to
registers 0x0-0xD
Enable write access to
registers 0x0-0xD
Output active
Output inactive
Set warning output to ’1’
Set warning output to ’0’
Table 27: Implemented commands
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TRIANGULATION SENSOR
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With command STARTUP/RESET internal state machines, counters, and the status register are reset. The
device waits for further commands.
Command OSC_OUT_ON enables the output of a
1 MHz clock (based on the system clock) through pin
WARN.
With command REG_PROT_ON the internal configuration register addresses 0x00 . . . 0x0D are protected
against overwriting. This write protection can be cancelled by command REG_PROT_OFF.
Status register
The status register is read out on a read access to
register 0x0F. The switching state, warning, and transimpedance mode from the last measurement cycle
are stored here, plus the last four individual differential comparator measurements. These can originate
from one measurement cycle or from various individual
measurement cycles with short measurement cycles.
KD(0) is the most recent and KD(3) the oldest result.
The switching state stored in the register is independent of SOCNO (see 15). Coding of TII is equivalent
to that of TIM(1:0) (Table 11).
Command TST_SO_ON sets switching output SO to
active and NSO to inactive regardless of the internal
SOI state (observe SOCNO and SOEN programming).
STATUS
Bit
Name
3:0
KD
Results of difference
comparator
Command TST_SO_OFF sets switching output SO to
inactive and NSO to active regardless of the internal
SOI state (observe SOCNO and SOEN programming).
5:4
TII
6
WARNI
7
SOI
Transimpedance of last
measurement
Warning from last
measurement cycle
Output from last
measurement cycle
Command TST_WARN_ON sets warning output
WARN to 1 regardless of the internal WARNI state.
Addr. 0x0F; bit 7:0
Description
R
Table 28: Status register 0x0F
Command TST_WARN_OFF sets warning output
WARN to 0 regardless of the internal WARNI state.
POWER DOWN RESET
The internal power-down reset (low active) is output
through NRES. The enable (rising edge) is delayed
(see R04).
CONFIGURATION NOTES
• Parameter SKO should be programmed to 0x5 so
that it is adjusted to suit the signal conditioning chain
in iC-LO (see Table 20).
• The light pulse width programmed using parameter
PW (see Table 10) should be at least 0.5 µs longer
than SKO.
• Operating mode SINGLE_MEASURE only functions
when FIN = FIM = 0x0 (see Table 18/19).
CHIP REVISION
The parameter REV in the iC-LO ROM provides the
chip revision.
REV
Code
Addr. 0x12; bit 7:0
Chip revision
0x0
0x1
0x2
0x3
0x4
iC-LO 0
iC-LO 1
iC-LO ZA
iC-LO ZB
iC-LO ZA1
0x5
0x6
...
0xFF
iC-LO Y
reserved
reserved
R
iC-LO
TRIANGULATION SENSOR
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SPI INTERFACE
During SPI communication (NCS low) an ongoing
measurement sequence in iC-LO is halted (LED off,
switching output off).
• REGISTER status/data
• REGISTER read (cont.)
• REGISTER write (cont.)
The SPI protocol is equivalent to iC-Haus standard SPI
Interface A0.1. The following implemented commands
are described therein:
• STATUS read
• INSTRUCTION write
APPLICATION NOTES
The diagram shows a possible IO-Link compatible system with iC-GF acting as a switch and reverse polarity
protection for supply voltages of between 9 and 30 V.
Configurable Photodiode Array
IN
IF
AC Transimpedance Amplifier
VREF
Far Channel
VREF
Near Channel
+
-
+
-
OF
ON
+
-
+
-
VD
VS
VTHD
2 MHz
Oscillator
Bandgap
Reference
Microcontroller
SPI Interface
SCK NCS
VCC3
VCC3
GND
GNDA
Power-Down
Reset
and FSM
KD
KSe
KSw
VCC
Low-Side
LED Treiber
VDD
LED
VCCL
NRES
NSO
SO
WARN
GNDL
iC-LO
CVCCL
10μF
CVCC
100nF
CVCC
1μF
VCC3
8.2K
RSET
GND
CFP
CFO/RX
OEN
IN2_MOSI
QCFG2_SCLK
IN1_TX
INV1_ESPI
QCFG1_NCS
ISET
NOVL_NDIAG
NUVD_MISO
CVCC3
1μF
VCC
Channel 2
VCC3
=1
FEEDBACK OUTPUT
Toff
VCC
VH
VHL
FEEDBACK COMPARATOR
SPI INTERFACE
CVH
1μF
DC/DC
CONVERTER
LVH
22μH
CONFIGURATION REGISTER
CONTROL LOGIC
LIN. REGULATOR
VBR VCC3
Overload
VCC3
Channel 1
VCC3
1
Undervoltage
VCC3
INPUT INTERFACE
STATUS
OUTPUT
..50mA
VN
VBR
iC-GF
LS2
HS2
LS1
HS1
VBO < VN
LINE OUTPUT
BIAS
VBR
VN
CFI
QN2
QP2
QN1
QP1
VBO
CVBR
1μF
CQ2
1nF
CQ1
1nF
CVBO
100nF
VN
Q2
LINE
Q1
9..30 V
VBO
TRIANGULATION SENSOR
MOSI MISO
+
-
+
-
+
-
Signal Processing
Programmable
Comparators
VREF
VTHSe
VTHSw
MOSI MISO SCK NCS GND
SPI Interface
Programmable Differential Amplifier
VREF
Adder
VREF
VREF
VDD
iC-LO
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Figure 7: Application schematic
It would also be possible to combine iC-LO and iC-DN/DP/DX as switches and iC-WD as a voltage regulator.
This would work for a supply voltage range of between 8 and 36 V.
iC-LO
TRIANGULATION SENSOR
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iC-Haus expressly reserves the right to change its products and/or specifications. An info letter gives details as to any amendments and additions made to the
relevant current specifications on our internet website www.ichaus.de/infoletter; this letter is generated automatically and shall be sent to registered users by
email.
Copying – even as an excerpt – is only permitted with iC-Haus’ approval in writing and precise reference to source.
iC-Haus does not warrant the accuracy, completeness or timeliness of the specification and does not assume liability for any errors or omissions in these
materials.
The data specified is intended solely for the purpose of product description. No representations or warranties, either express or implied, of merchantability, fitness
for a particular purpose or of any other nature are made hereunder with respect to information/specification or the products to which information refers and no
guarantee with respect to compliance to the intended use is given. In particular, this also applies to the stated possible applications or areas of applications of
the product.
iC-Haus conveys no patent, copyright, mask work right or other trade mark right to this product. iC-Haus assumes no liability for any patent and/or other trade
mark rights of a third party resulting from processing or handling of the product and/or any other use of the product.
As a general rule our developments, IPs, principle circuitry and range of Integrated Circuits are suitable and specifically designed for appropriate use in technical
applications, such as in devices, systems and any kind of technical equipment, in so far as they do not infringe existing patent rights. In principle the range of
use is limitless in a technical sense and refers to the products listed in the inventory of goods compiled for the 2008 and following export trade statistics issued
annually by the Bureau of Statistics in Wiesbaden, for example, or to any product in the product catalogue published for the 2007 and following exhibitions in
Hanover (Hannover-Messe).
We understand suitable application of our published designs to be state-of-the-art technology which can no longer be classed as inventive under the stipulations
of patent law. Our explicit application notes are to be treated only as mere examples of the many possible and extremely advantageous uses our products can
be put to.
iC-LO
TRIANGULATION SENSOR
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ORDERING INFORMATION
Type
Package
Order Designation
iC-LO
oBGA™ LO1C
iC-LO oBGA LO1C
Evaluation Board
iC-LO EVAL LO1D
For technical support, information about prices and terms of delivery please contact:
iC-Haus GmbH
Am Kuemmerling 18
D-55294 Bodenheim
GERMANY
Tel.: +49 (61 35) 92 92-0
Fax: +49 (61 35) 92 92-192
Web: http://www.ichaus.com
E-Mail: [email protected]
Appointed local distributors: http://www.ichaus.com/sales_partners