E909.01
Optical switch with high ambient light immunity
Features
General Description
● Small footprint, SOP16 or TSSOP16 package
The E90901 is an optical switch based on the
HALIOS (High Ambient Light Independent Optical
System) working principle, which is very effective
in suppression of ambient light and has inherent
self calibration capabilities to eliminate disturbances caused by housing reflections and scratches.
● Operational up to 200klux ambient light
● Proximity, touch, switch and wipe function
● Supply voltage range: 3.3V to 5.0V
● Parameter adjustment and functional
data read back via SPI interface
● Status output for switch and proximity function
The device is capable of indicating the situation
when objects are entering the detection area of
the sensor. Further a switch event is recognized
when an object touches the surface of the sensor.
Both functions are available with the static output
signals PROX and TOUCH.
● -40°C to 85°C operating temperature
Applications
● Waterproof switches
● switch for anti-septic environment
Additionally it is possible to observe the movement of objects in the detection area. The corresponding measurement values are proportional to
the distance and the velocity of the object and can
be read out via SPI interface.
● Switch with background lighting function
in case of approach
● Mechanic-less key pad array
● Motion switch for example in vacuum
cleaner application
● Proximity sensing
Typical Application
Translucent
Surface
Sending
LED
Comp.
LED
100U
100N
Photo Diode
TIN
AVSS
LEDC
DVSS
AVDD
SCK
MOSI
SYI
PROX
ENSPI
LEDS
TOUCH_B
E90901
SYO
TOUCH_A
SW TO
DVDD
VDD
1MEG
R1
1MEG
R2
Switch
Proxim ity
Figure 1: Typical application
ELMOS Semiconductor AG
Specification
1 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
Package SOP16/TSSOP16
AVDD
1
TIN
SCK
16
MOSI
E909.01
AVSS
SYI
LEDC
PROX
DVSS
SYO
LEDS
TOUCH_b / MISO
DVDD
TOUCH_a / LDB
ENSPI
8
SWTO
9
Figure 2: Pin-Out E909.01
Pin Description
Name
AVDD
TIN
AVSS
LEDC
DVSS
LEDS
DVDD
ENSPI
SWTO
TOUCH_a
/ LDB
Type 1)
AI
AI
AG
AO
DG
AO
AI
DI
DI
A I/O
DI
11
TOUCH_b
/ MISO
A I/O
DZ
12
SYO
D Z*
13
14
15
16
PROX
SYI
MOSI
SCK
DI
DI
DI
DI
Pin Nr.
1
2
3
4
5
6
7
8
9
10
Function
Analog supply
Transimpedance amplifier input
Analogue ground
Output compensation LED
Digital ground
Output sending LED
Digital supply
Enables the SPI Interface
Select touch or toggle mode
Output of the „Touch“ function with an analogue switch of typical 30
Ohm between pin 10 and pin 11. In SPI operation mode
(ENSPI=HIGH) this pin is redefined to the LDB „chip select“ input
Output of the „Touch“ function with an analogue switch of typical 30
Ohm between pin 10 and pin 11. In SPI operation mode this pin is
redefined to the MISO „master input slave output“ output
Synchronisation output (*high ohmic for a short time after power on
and SPI reset)
„Proximity“ function output (active low)
Synchronisation input
SPI „master output slave input“
SPI serial clock
1) A = Analog, D = Digital, G = Ground, I = Input, O = Output, I/O = Bidirectional and Z = Tristate Output
Notice:
ELMOS Semiconductor AG reserves the right to make changes to the product contained in this publication without notice. ELMOS Semiconductor AG assumes no responsibility for
the use of any circuits described herein, conveys no licence under any patent or other right, and makes no representation that the circuits are free of patent infringement. While the
information in this publication has been checked, no responsibility, however, is assumed for inaccuracies.
ELMOS Semiconductor AG does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can reasonably be
expected to cause failure of a life-support system or to significantly affect its safety or effectiveness. Products are not authorized for use in such applications.
ELMOS Semiconductor AG
Specification
2 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
SOP16 Package Outline and Description
N
-BE
Index Area
H
❁
Detail 'B'
L
1 2 3
h X 45°
Detail 'A'
Detail 'B'
e
A
A1
D
Mould Parting
Line
-C-
C
Seating
Plane
-A-
B
Detail 'A'
Figure 3: SOP16 Wide Body Package
Description
Symbol
Distance from the seating plane to the highest
point of body
Distance between the seating plane and the
base plane
Width of terminal leads, including lead finish
Coplanarity lead to lead
Thickness of leads measured in a plane
perpendicular to the seating plane including
lead finish.
The longest body dimension measured
perpendicular to the body width E
The smallest body width dimension
Linear spacing between true lead positions
which applies over the entire lead length or at
the gauge plane
Largest overal package width dimension of
mounted package
Body chamfer angle
Length of terminal for soldering to substrate
Number of terminal positions
Angle of lead mounting area
ELMOS Semiconductor AG
min
mm
typ
min
inch
typ
max
max
A
-
-
2.64
-
-
.104
A1
0.10
-
-
.004
-
-
B
b2
C
0.36
0.23
-
0.51
0.10
0.33
.014
.009
-
.020
.004
.013
D
10.11
-
10.50
.398
-
.413
E
e
7.40
-
1.27
7.60
-
.291
-
.050
.299
-
H
10.11
10.65
.398
h
L
N
a
0.25
0.51
0°
0.75
1.01
8°
.010
.020
0°
Specification
3 / 29
16
-
Date:24.02.04
.419
16
-
.029
.040
8°
QM-No.:03SP0277E.02
E909.01
TSSOP16 Package Outline and Description
Symbol
Description
Distance from the seating plane to the highest point of body
Distance between the seating plane and the base plane
Thickness of package body
Width of terminal leads, including lead finish
Thickness of leads measured in a plane perpendicular to the
seating plane including lead finish.
The longest body dimension measured perpendicular to the
body width E
The smallest body width dimension
Linear spacing between true lead positions which applies over
the entire lead length or at the gauge plane
Largest overall package width dimension of mounted package
Body chamfer angle
D
4.90
-
5.10
E1
e
4.30
-
4.40
0.65
4.50
-
Number of terminal positions
Tolerances
Specification
6.40 BSC
-
E
Q1
L
N
aaa
ddd
Length of terminal for soldering to substrate
ELMOS Semiconductor AG
A
A1
A2
b
c
Q 2/3
Lead angle
Dimension (mm)
typ
0.90
-
min
0.05
0.80
0.19
0.09
4 / 29
0
-
0.45
16
0.10
0.20
Date:24.02.04
max
1.20
1.05
0.30
0.20
12°
8
0.75
QM-No.:03SP0277E.02
E909.01
1. Working Principle
1.1. Block Diagram
AVDD
DVDD
R
1K
Transimpedance amplifier
TIN
Filter
Synchronous Demodulator
+
VREF
-
Control - Logic
Digital - Integrator
LEDS
-1
I_15
SCK
MOSI
Detection
SWTO
Algorithm
TOUCH_a
ENSPI
DAC
VDD
10U
SPI
Synchronizer
CLO CK
TOUCH_b
LEDC
PROX
DVSS
AVSS
SYI
SYO
Figure 5: Block Diagramm E90901
The high ambient light suppression using the HALIOS principle is based on two light sources which are
clocked by inverted phases. The photo-current receiver amplifies the difference of the received signal in both
clock phases and modulates the light source intensity in a negative feedback loop in order to compensate the
received signal to zero. Thus the input amplifier is always regulated to it´s most sensitive operation condition
independent of ambient light.
The receiving path uses a transimpedance amplifier with DC-current control to transfer the photo current into
a voltage. The signal is then amplified and filtered to remove disturbing signals and amplifier offsets. The
demodulator samples the voltages at the output of the amplifier synchronously to the LED clocks, takes the
difference of the signal in phase A and phase B and delivers the sign of this difference to the digital
integrator.
The transmitting path produces the signals for the LED modulation by converting the integrator output to an
analogue voltage. The output drives the compensation LED (LEDC) as shown in figure 4 with a voltage
controlled current source of maximum 1.5mA output current. The sending LED (LEDS) is driven by a
constant current of 10mA. Both outputs are clocked synchronously to the demodulator.
The detection algorithm analyses the data sequence of the digital integrator to detect if an object is
approaching to the sensor and if an object has touched the surface of the switch.
1.2. Overview Basic Functions
When an object appears in the detection range of the sensor the signal PROX is activated. If a touch on the
sensors surface has occured this is signalled by closing an analogue switch of 40 Ohm between the pins
TOUCH_a, TOUCH_b. With a wipe over the sensors surface a reset of the detection algorithm is activated.
In order to reduce the current consumption the measurement cycle is activated only for a short time T measure.
ELMOS Semiconductor AG
Specification
5 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
During the passive time Tpassive the IC is switched to an operation mode with reduced current consumption.
When an object is in the detection area of the sensor the proximity signal is activated and the sampling rate is
high. If no object is detected the sensor is switched to stand-by mode with reduced sampling rate in order to
minimize the mean current consumption.
To change this default configuration a full bidirectional SPI interface consisting of the pins LDB, SCK, MOSI
and MISO can be activated with the pin ENSPI. It is possible to adjust several thresholds and time constants
which are used for the proximity, touch and wipe function. Additionally reading back data from the switch to
the supervising µ-Controller is possible. Then the output of the digital integrator can be observed directly by
the µC and it is possible to implement different algorithms for signal detection.
If several switches are located near together the measurement phases can be synchronised in order to
minimise disturbances between the switches. The synchronisation bus consists of the pins SYI and SYO and
connects all switches in a loop.
1.2.1. Synchronization
The synchronisation is done by passing a pulse from one switch to the next. The sensor which has activated
the measurement cycle switches the output SYO to 'HIGH'. When the first switch delays the new cycle until
the passive time Tpassive has passed. The first switch is defined with a pull-up resistor at pin SYO. The
synchronisation leads to reduced noise and improves the ambient light suppression.
If the synchronization pulse is observed by the µC it is possible to delay the SPI commands until the
measurement cycles are finished.
1.2.2. Active - and Stand-by - Operation Mode
To reduce the current consumption the measurement phase is only activated for a short time of 25 clock
periods (200 µs) and the LED´s are clocked with 125 kHz. Together with a settling time for the amplifiers the
total measurement time has a value of Tmeasure = 464 µs. Afterwards during the passive time the measurement is stopped and the LED´s are switched off. When an object (movement) is detected and the proximity
signal becomes '0' the sensor is in the active operation mode for minimum 260 ms (minimum active time). In
this case the measurement is activated with a rate of 244 Hz. When no movement has been detected during
this time the sensor is switched to stand-by mode and the sampling rate is reduced to 15 Hz. If the object is
still in the detection area (without a movement) the PROX-output stays active ('0') independently of the
operation mode (default).
By connecting the PROX output to the interrupt pin of the supervising µC it is possible to use the proximity
event as a wake-up signal for the µC.
1.2.3. Detection Algorithms
The algorithms for detecting the switch state observe the integrator output which is proportional to the
modulation current of the compensation LED. If no object is in the detection area of the sensor and the
regulation loop has settled the integrator signal has a static value. If an object approaches to the sensor the
integrator output changes its value and if a threshold value is reached the proximity signal PROX is activated.
To detect the touch down event additionally the 1st and 2nd derivative of the integrator output is used. These
values are functions of the objects velocity and acceleration. A touch down is detected if the object is
approaching with a minimum velocity, stops on the sensors surface with a minimum of negative acceleration
and remains after the touch down for a minimum time of 130 ms on the surface of the sensor without moving.
The time criterion is used to be sure that it was a valid TOUCH event on the sensors surface.
If the object is removed from the sensors surface the stand-by mode is activated again if the output of the
integrator reaches the old value which it had before entering the active mode. If something falls onto the
surface and activates the TOUCH a time-out function switches back into stand-by mode after global time out
(TIMOV) and the recent static value of the integrator output is used as the new reference value for the
proximity function.
The TOUCH signal output (on pins 10,11 or via SPI) depends on the pin SWTO. When this pin is connected
to ground TOUCH is only active as long as the object touches the surface (touch-mode). When it is
connected to supply it is in toggle-mode: A TOUCH event closes the switch and the TOUCH output stays
active as long as the next TOUCH event opens the switch.
With a wipe over the sensors surface a reset in detection algorithm is activated. If after a touch some dirt is
left on the sensor the system would not turn to stand-by mode because there is a higher reflection. In this
case a wipe stops the time-out and a new reference will be found.
ELMOS Semiconductor AG
Specification
6 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
2. General Device Specification
2.1. Absolute Maximum Ratings
Currents are positive into, and negative out of the specified terminal.
Parameter
Condition
Symbol
min
max
Unit
Supply voltage range VS
continuously
VS
-0,3
+5.5
V
150
°C
150
°C
240
°C
Junction temperature
TJ
Storage temperature range
TSTG
Soldering temperature
TLead
-55
(10 Seconds)
Stresses beyond those listed under „absolute maximum ratings“ may cause permanent damage to the
device. These are stress ratings only, and functional operation of the device at these or any other conditions
beyond those indicated above is not implied. Expose to absolute maximum rated conditions for extended
periods may affect device reliability and are not permitted.
2.2. Recommended Operating Conditions
The following conditions apply unless otherwise stated.
Parameter
Conditions
Symbol
min
typ
max
Unit
Supply voltage range
TAMB £ +85 °C
VBAT
3.0
3.3
5.5
V
Ambient operating temperature range
TOPT
-40
27
85
°C
Junction temperature
TJ
-40
27
125
°C
2.3. Electrostatic Discharge Sensitivity
This integrated circuit can be damaged by ESD. ELMOS recommends that all integrated circuits must be
handled with appropriate precautions. Failure to observe proper handling and installation procedures can
cause damage.
ESD damage can range from subtle performance degradation to complete device failure.
ELMOS Semiconductor AG
Specification
7 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
3. Detailed Electrical Characteristics
TA = -40°C to 85°C and TA = TJ. Typical values are at TA = +25°C and AVdd/DVdd 3.3V (unless otherwise
noted).
3.1. Receiving Path
Spec.-No Parameter
Symbol
Min
Typ
Max
Unit
70
100
130
kW
Input terminal TIN
1
Transimpedance
Rf
2
Idc
1000
3
DC-current compensation optimized for
SFH229 (OSRAM PIN Photodiode)
Capacitance of photo diode @ 0.7V
Cd
50
100
pF
4
Voltage at TIN-Pin
Vtin
0.7
1
V
5
Settling time (1mA step)
Ts
150
us
6
Corner frequency 1st highpass filter
fg1
20
kHz
7
1st gainstep 1st amplifier
G01
17
dB
8
2nd gainstep 1st amplifier
G02
23
dB
9
Corner frequency 2nd highpass filter
fg2
20
kHz
10
1st gainstep 2nd amplifier
G11
11
dB
11
2nd gainstep 2nd amplifier
G12
23
dB
12
Minimum total gain
Gmin
128
dBW
13
Maximum total gain
Gmax
146
dBW
14
Gain step width
Gstep
6
dBW
15
Center frequency
fc
125
kHz
ELMOS Semiconductor AG
Specification
8 / 29
0.3
Date:24.02.04
mA
QM-No.:03SP0277E.02
E909.01
3.2. Transmitting Path
Spec.-No Parameter
1.1
DAC resolution
Symbol
N
Min
Typ
10
Max
Unit
bit
1.2
DAC INL
Ei
2
lsb
1.3
DAC DNL
Ed
2
lsb
1.4
Dac output voltage at full scale
Vmax
1.22
V
Spec.-No Parameter
SPI-Param.
FIXS HICS
Symbol
Min
Typ
Max
Unit
0.3
0.5
mA
4
Output terminal LEDS
2.1
Bias Current (permanent
part of LED current)
2.2
Current LEDS (switched
part of LED current)
2.3
Current LEDS (fixed level,
switched part of LED
current)
Spec.-No Parameter
ICb
'0'
IS0min
IS0max
IS1min
IS1max
ISfix0
36
10
mA
mA
mA
mA
mA
'1'
ISfix1
20
mA
'0'
'0'
'0'
'1'
'1'
'1'
SPI-Param.
HICC
Symbol
18
6
Min
Typ
Max
Unit
0.25
0.5
mA
0.05
mA
Output terminal LEDC
3.1
Bias Current (permanent
part of LED current)
3.2
Current LEDC
(switched part of LED
current)
ICb
'0'
IC0min
IC0max
'1'
mA
IC1min
IC1max
ELMOS Semiconductor AG
0.85
Specification
9 / 29
0.05
1.5
mA
mA
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
3.3. Internal References and Parameters
Spec.-No Parameter
1
Reference voltage
2
Bias current
3
Oscillator frequency
Symbol
Vref
Min
1.45
Typ
1.65
Max
1.85
Unit
V
Ib
7
10
15
mA
fosc
300
500
700
kHz
Symbol
Min
Typ
Max
Unit
0.4
V
3.4.SPI Interface
3.4.1.SPI DC characteristics
Spec.-No Parameter
Conditions
Output terminal Touch_b / MISO
SPI-Mode:
SPI enabled
1.1
Output voltage low
I = 0.5mA
1.2
Output voltage high
I = -0.2mA
VDD - 0.4
1.3
Tristate leakage
0 < VMISO < V5
-5
Spec.-No Parameter
Conditions
Symbol
Min
V
Typ
5
µA
Max
Unit
Input terminal Touch_a / LDB
SPI-Mode:
SPI enabled
2.1
Input voltage low
-0.3
0.4 VDD
V
2.2
Input voltage high
0.6 VDD
VDD + 0.3
V
2.3
Hysteresis1
2.4
Leackage
VDhys
0 < VIN < VDD
mV
0
-5
5
µA
Input terminals SCK, MOSI
3.1
Input voltage low
VDSl
-0.3
0.4 VDD
V
3.2
Input voltage high
VDSh
0.6 VDD
VDD + 0.3
V
3.3
Hysteresis1
VDhys
3.4
Leackage
ELMOS Semiconductor AG
0 < VIN < VDD
Specification
0
-1
10 / 29
mV
1
Date:24.02.04
µA
QM-No.:03SP0277E.02
E909.01
3.4.2.SPI AC characteristics
Spec.-No Parameter
Conditions
Symbol Min Typ
Max
Unit
Terminal LDB, SCK
SPI-Mode:
SPI enabled
1.1
Time of ¯ LDB (10%) to SCK (90%)1
TLS1
90
ns
1.2
Time to ¯ SCK (10%) to LDB (90%)1
TLS2
80
ns
Spec.-No Parameter
Conditions
Symbol Min Typ
Max
Unit
8.1
MHz
Terminal SCK
2.1
Period SPI clock
FSCK
Terminal MOSI, SCK
3.1
Data setup time: Time from changing
MOSI (10%, 90%) to SCK(90%)1
TSET
30
ns
3.2
Data hold time: Time of SCK (90%) to
changing MOSI (10%,90%)1
THOLD
30
ns
3.3
Time of ¯ SCK (10%) to stable MISO (10%, Load capacitance
at MISO < 15 pF.
90%)1
TVAL2
30
ns
Terminal LDB, MISO
SPI-Mode:
4.1
4.2
4.3
1
SPI enabled
Time of ¯ LDB (10%) to stable MISO (10%, Load capacitance
at
90%)1.
MISO < 15 pF
Load capacitance
Time of LDB (90%) to high impedance
at MISO < 15 pF
state of MISO1.
Time between SPI cycles: LDB at high level
(90%)1.
TVAL1
20
80
ns
TLZ
20
80
ns
TLH
250
ns
not production tested
Figure 6: SPI bus timing diagram
ELMOS Semiconductor AG
Specification
11 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
3.5. Status output
Spec.-No Parameter
Conditions
Symbol
Min
Typ
Max
Unit
Output terminal Touch_a / LDB - output terminal Touch_b / MISO
SPI-Mode:
1.1
1.2
SPI disabled
Resistance between
both pins
(Resistance is VDD
dependant)
100
W
30
mA
Typ
Max
Unit
0.5
1.0
V
40
Maximum current
Spec.-No Parameter
Conditions
Symbol
Min
Output terminal PROX
SPI-Mode:
SPI disabled
2.1
Output voltage low
IPROX = 5mA
2.2
Input voltage high
VDSI
-0.3
0.4 VDD
V
2.3
Input voltage low
VDSh
0.6 VDD
VDD+ 0.3
V
2.4
Leackage
-5
5
µA
Max
Unit
0 < VIN < Vdd
3.6. Synchronisation
Spec.-No Parameter
Conditions
Symbol
Min
Typ
Input terminal SYI
1.1
Input voltage low
VDSl
-0.3
0.4 VDD
V
1.2
Input voltage high
VDSh
0.6 VDD
VDD + 0.3
V
1.3
Hysteresis1
VDhys
1.4
Leackage
0 < VIN < VDD
0
-5
mV
5
µA
0.4
V
Output terminal SYO
2.1
Output voltage low
I = 0.5mA
2.2
Output voltage high
I = -0.2mA
VDD - 0.4
2.3
Tristate leakage
0 < VSYO < V5
-5
ELMOS Semiconductor AG
Specification
12 / 29
V
5
Date:24.02.04
µA
QM-No.:03SP0277E.02
E909.01
3.7. Mode selection
Spec.-No Parameter
Conditions
Symbol
Min
-0.3
Typ
Max
Unit
0.4 VDD
V
VDD + 0.3
V
Input terminal ENSPI, SWTO
1.1
Input voltage low
VDSl
1.2
Input voltage high
VDSh
1.3
Hysteresis1
VDhys
1.4
Level for Testmode
Selection
1.5
Leackage
0.6 VDD
0
0.5 VDD
-100mV
0 < VIN < VDD
0.5 VDD
-5
mV
V
0.5
VDD+100
mV
5
µA
3.8. Supply
Spec.-No Parameter
Conditions
Symbol
Min
Typ
Max
Unit
3.0
3.3
5.5
V
Input terminal AVDD
1.1
Supply voltage
VDD
1.2
Supply current SYI = 0;
Slave mode; standby
Supply current SYI = 1;
Slave mode; active;
FRQVAL=1
Supply current STOP mode (Oscillator
off)
IADD
14
mA
IADD
215
mA
IADD
0
mA
1.3
1.4
Input terminal DVDD
2.1
Supply voltage
2.2
Supply current LEDC,LEDS open,SYI =0;
Slave mode; standby
Supply current LEDC,LEDS open,SYI =1;
Slave mode; active;
FRQVAL=1
Supply current STOP mode (Oscillator
off)
2.3
2.4
VDD - 0.1
VDD
VDD + 0.1
V
IDDD
125
mA
IDDD
125
mA
IDDD
5
mA
Supply ripple
3.1
Supply ripple
ELMOS Semiconductor AG
AVDD, DVDD, f<100kHz
Specification
10
13 / 29
Date:24.02.04
mV
QM-No.:03SP0277E.02
E909.01
4. Functional Description
4.1. Digital integrator
The digital part of the HALIOS loop is a digital integrator which integrates the output of the synchronous
demodulator in a 10 bit register. This 10 bit word is DA-converted to modulate the compensation LED.
During a measurement cycle this integrator works with a frequency of 125 kHz.
4.1.1. Integrator stepsize
To follow fast and large changings the stepsize of integration can vary between 1- 8 LSBs.
The maximum stepsize can be adjusted with the SPI parameter SELACC and the accelerated integration can
be switched off with the parameter ACC_ON (see 4.3.3).
4.1.2. Measurement cycle
A measurement cycle starts with switching on the analogue components. After the amplifiers have settled to
a DC value the HALIOS loop is closed and the integrator is working for 25 clock cycles. A whole
measurement cycle takes 464 ms.
4.2. Detection-Algorithm
4.2.1. Operation modes
The E90901 has two operation modes with different sampling rates. The sampling rate describes the time
distance between two measurement cycles. During a measurement cycle the digital integrator approximates
the value to compensate the difference between the LED signals. If there is no moving object in the detection
area it is not necessary to operate with a high sampling rate. So the system is in stand-by mode and the
measurement cycles follow every Tstandby= 64 ms. If an object is recognized in the detection area the system
changes into active mode with a sampling period of Tactive= 4 ms.
4.2.2. Event detection
The Algorithm is able to detect three different events:
1. PROX:
indicates a movement (proximity) in the detection area.
2. TOUCH:
indicates a touch down on the sensors surface.
3. WIPE:
indicates a wipe over the sensors surface.
4.2.2.1. Proximity event
If a moving object is detected the signal on output pin PROX (see figure 2) is '0'. There are two different
modes for this output pin which can be chosen with the parameter HOLDPROX (see 4.3.3). In case of default
(HOLDPROX = '1') the PROX output is independent of the operation mode and held '0' as long as the object
is in the detection area. When HOLDPROX = '0' the PROX output is '0', when the system is in active mode.
The internal PROX signal (=not STANDBY) can also be read out via SPI (see 4.3.3).
To change the sensibility for proximity detection the parameters THZ1, PROXNUM1, PROXNUM2 und
DYNSTEP (see 4.3.3; figure 6) can be changed via SPI.
ELMOS Semiconductor AG
Specification
14 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
4.2.2.2. Touch event
To detect a valid TOUCH signal five conditions must be fulfilled:
1. The dynamic (distance between reference and recent value) must pass the minimum which is set with the
parameter THZ2 (see 4.3.3; figure 7).
2. The approach to the surface must pass a minimum speed which can be tuned by THD1 (see 4.3.3; figure
7).
3. The object must stop on the surface with a minimum of negative accelleration which is defined with THA
(this parameter is coupled with THD1, see 4.3.3; figure 7).
4. After touch down the finger must be left calm on the surface. The deviation THD0, called touch
tolerance, depends on the dynamic and is adjusted automatically. Higher dynamic causes higher
tolerance.
5. The finger must stay calm for the hold time Ttouch which can be adjusted by the parameter TOTIM.
When all this conditions were fulfilled the switch between the pins TOUCH_a and TOUCH_b (see figure 2) is
closed when the SPI is disabled (ENSPI), otherwise the TOUCH signal can be read out via SPI.
With the pin SWTO you can decide between touch- and toggle-mode. In touch-mode the TOUCH signal
output (on pins 10,11 or via SPI) is only active as long as the object touches the sensors surface. In togglemode every TOUCH event toggles between open and closed switch.
4.2.2.3. Wipe event
When the system is in touch-mode and a wipe over the surface is detected a reset in the detection algorithm
is activated and the system changes to stand-by mode.
When it is in toggle-mode the WIPE event can also be read out via SPI but in case of default no reset is
activeted. This is to prevent that the switch opens with an accidental movement over sensors surface.
With the SPI parameter RSWIPE it is possible to enable this reset also in toggle-mode.
DMAX
SAMP
4.2.3. Timeout
If the system is in active mode and after
the time Ttimeout no further movement is
recognized it switches back to stand-by
mode. This time can be set with the
parameter TIMOV (see 4.3.3).
minimum dynamic (THZ2)
THD0
touch
tolerance
DMAX
MAX
REF
DREF
2. proximity threshold (2 x THZ1)
1. proximity threshold (THZ1)
4.2.4. Reset
n
A reset of the detection algorithm can be
done via SPI with RESET (see 4.3.3).
D
velocity threshold (THD1)
n
A
n
acceleration threshold (THA)
Figure 7: Signals and parameters
ELMOS Semiconductor AG
Specification
15 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
4.3. SPI Interface
16 data bits are sent to the E90901 via SPI. The first four bits contain the address bits. These four bits tell the
E90901 its general operation. The next four bits contain the Data information. The last eight bits are not used.
The SPI interface consists of 4 pins:
1.
2.
3.
4.
MOSI
SCK
LDB
MISO
:
:
:
:
Master Out Slave In :
Serial Clock :
Load (active low):
Master In Slave Out :
µC
µC
µC
ASIC
=> ASIC
=> ASIC
=> ASIC
=> µC
4.3.1. SPI Transmission
Each transmission starts with a falling edge on LDB and ends with a rising edge. During transmission commands and data are shifted according to the following rules
1.
2.
3.
4.
LDB line is active (active 'LOW').
MOSI data are shifted in on the rising SCK edge MSB first and LSB last.
MOSI data are read on the falling SCK edge.
A command is only executed on the rising edge of LDB when 16 clock cycles are counted durning the last
transmission.
5. MISO is active during LDB is 'LOW' and is tristated during LDB is 'HIGH'.
6. SCK should remain 'LOW' after the 16th SCK falling edge.
The following diagram shows one data transmission over the SPI-bus. For exact timing see chapter 3.4.2.
Figure 8: Example of a correct data transmition, command h2200
The adjusted parameter is valid with the first falling edge of the internal oscillator (CLK_500K) after LDB is
'HIGH'. In the example of figure 8 THZ1 is set to 4 LSB.
4.3.2. MISO Line
16 bits of Data are returned to the µC on the rising edge of SCK. The data that is returned contains information about the state of the switch and the value of the DAC or the received command. This is depending
on the parameter RETUR (default 'LOW').
RETUR
MISO LINE
MSB [1]
[2]
[3]
[4]
[5]
'LOW'
not STANDBY
MOVEDO PRETO
TOUCH
WIPE
'HIGH'
not STANDBY
MOVEDO PRETO
TOUCH
WIPE
[6:13]
[14]
COUNT[9:0]
ADDR[0:3]
DATA[0:3]
[15]
LSB[16
]
TMODE
RETUR TMODE TMODE
In the example of figure 8 the received bits are: 1110001111111110 (with default parameters).
This means the E90901 is in active mode (internal PROX,here: high active !), the states MOVEDO and
PRETO are low active and TOUCH, WIPE are high active. The integrator value is
COUNT=“0111111111“(511) and the LSB: TMODE (high active) indicates that the E90901 is not in testmode.
ELMOS Semiconductor AG
Specification
16 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
4.3.3. Address decoding
Address
Data
“0000”
“0000”
He Default
x
Signal
Description
00**
-
-
-
Unused
“0001” 01**
-
-
-
Unused
“0010” 02**
-
-
-
Unused
“0011” 03**
-
-
-
Unused
“0100” 04**
-
-
-
Unused
“0101” 05**
-
-
-
Unused
G0
disabled
“0110” 06** enabled
“0111” 07**
“1000” 08** disabled
enabled
G1
“1001” 09**
“1010” 0A** enabled
HICC
HICS
disabled
High current for compensation LED.
disabled
High current for sending LED.
enabled
FIXS
“1111” 0F**
ELMOS Semiconductor AG
Gainsetting 12 dB.
enabled
“1101” 0D**
“1110” 0E** enabled
disabled
enabled
“1011” 0B**
“1100” 0C** disabled
Gainsetting 6 dB.
disabled
Fixed current for sending LED.
enabled
Specification
17 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
Address
Data
He Default
x
Signal
„0001“
“0000”
10** enabled
ACC_ON
Description
disabled
“0001” 11**
“0010” 12**
enabled
4 LSB
SELACC
4 LSB
“0011” 13**
“0100” 14**
“0111” 17**
-
-
-
SELDELAY
disabled
“1001” 19**
enabled
“1010” 1A** disabled
RSWIPE
disabled
“1011” 1B**
“1101” 1D**
enabled
return
counter
value
RETUR
return counter
value
return command
“1110” 1E** enabled HOLDPROX
disabled
“1111” 1F**
enabled
ELMOS Semiconductor AG
Select the maximum integrator
stepsize (see 4.1) .
8 LSB
“1000” 18** disabled
“1100” 1C**
En/Disables the counters
acceleration (see 4.1) :
- enabled -> step size: 1-8 LSB ,
- disabled -> step size: 1 LSB.
Specification
18 / 29
Unused
En/Disables an additional touch
time, which is depending on the
signals dynamic. Its used for
synchronization (see 4.4)
Disables the reset caused by a
detected WIPE signal when the
switch is in toggle-mode
(SWTO='1') (see 4.2).
RETUR switches the data which is
send out via MISO,
see section 4.1.3
If enabled the PROX output is held
active (low) as long as an object is
inside the detection area.
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
Address Data
„0010“
“0000”
Hex Default
20**
4 LSB
Signal
THZ1
Description
Sets to 3 LSB
“0001” 21**
Sets to 4 LSB
“0010” 22**
Sets to 4 LSB
“0011” 23**
Sets to 5 LSB
“0100” 24**
“0111” 27**
-
-
-
“1000” 28**
32 LSB
THZ2
Sets to 8 LSB
“1001” 29**
Sets to 16 LSB
“1010” 2A**
Sets to 32 LSB
“1011” 2B**
Sets to 64 LSB
“1100” 2C**
Sets to 128 LSB
“1101” 2D**
Sets to 192 LSB
“1110” 2E**
Sets to 256 LSB
“1111” 1F**
Sets to 512 LSB
ELMOS Semiconductor AG
1st Threshold
promixity.
for
sensitive
2nd Threshold for
promixity is 2*THZ1.
not sensitive
Unused
Minimum dynamic for
touch detection
sensitive
not sensitive
Specification
19 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
Address Data
„0011“
Hex Default
“0100”
Description
“0000” 30**
“0111” 37**
-
-
-
“1000” 38**
4 LSB /
-4 LSB
THD1 / THA
4 LSB / -1LSB
“1001” 39**
(soft)
Unused
Velocity and
acceleration
threshold for
touch.
4 LSB / -4 LSB
very soft
soft
“1010” 3A**
7 LSB / -7 LSB
middle
“1011” 3B**
10 LSB / -10 LSB
hard
“1100” 3C**
“1111” 3F**
Address
Signal
-
Data Hex Default
“0000” 40**
“0111” 47**
-
“1000” 48** 130 ms
-
-
Unused
Signal
Description
-
-
Unused
TOTIM
65 ms
“1001” 49**
130 ms
“1010” 4A**
130 ms
“1011” 4B**
260 ms
“1100” 4C**
48 s
TIMOV
TOUCHED
32 s
“1101” 4D**
48 s
“1110” 4E**
60 s
“1111” 4F**
No
timeout
ELMOS Semiconductor AG
Specification
20 / 29
Touch time (holdtime),
constant part of Tvalid
PROX
Duration
of
timeout when
12.5min system state
.
is TOUCHED
16 min. or PROX
8 min.
No
timeout
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
Address Data Hex Default
“0101”
“0000” 50**
-
“0001” 51** enabled
Signal
Description
-
-
Unused
OSCON
disabled
Switches internal oscillator off
“0010” 52**
“0100” 54**
-
-
-
Unused
“0101” 55**
-
RESET
-
Resets the whole digital part,
+
OSCON
“0110” 56**
“1111” 5F**
-
-
Address Data Hex Default
“0110”
“0000”
6***
Switches the oscillator on
-
-
Unused
Signal
Description
-
-
Unused
“1111”
Address
“0111”
Data Hex Default
“0000”
70**
2
Signal
DYNSTEP
“0001” 71**
“0010” 72**
“0011” 73**
“0100” 74**
2
PROXNUM1
“0101” 75**
“0110” 76**
“0111” 77**
“1000” 78**
“1001” 79**
-
-
“1010” 7A**
2
PROXNUM2
Address
Data
“1XXX”
“XXXX”
-
ELMOS Semiconductor AG
Sets to 0 If PROXCNT, which counts
the number of subsequent
Sets to 1 samples that pass the 1st
Sets to 2 threshhold THZ1, is greater
than PROXNUM1, then
Sets to 3 proximity is detected.
-
-
Signal
sensitive
not sensitive
sensitive
not sensitive
Unused
Sets to 2 If POSCNT or NEGCNT >
PROXNUM2
Sets to 3 proximity is detected
-
Hex Default
****
Sets to 0 Pos./Neg. steps greater than
DYNSTEP are counted up in
Sets to 1 the dynamic counters:
Sets to 2 NEGCNT and POSCNT,
otherwise they are in reset.
Sets to 3
-
“1011” 7B**
“1100” 7C**
“1111” 7F**
Description
sensitive
not sensitive
Unused
Description
-
Test mode commands
Specification
21 / 29
Don't use
Date:24.02.04
!
QM-No.:03SP0277E.02
E909.01
4.4. Synchronisation
The synchronisation is done by passing a pulse from one switch to the next. Each switch has an input SYI
and an output SYO. The output SYO is connected to the input SYI of a neighbouring E90901 in a chain of
E90901s or connected to it own SYI if there is only one switch. The output SYO is 'HIGH' when an E90901 is
conducting a measurement cycle. An E90901 activates when
1. It is a slave E90901 and there is a falling edge on the input SYI.
2. It is the master E90901 and the passive time has elapsed.
VDD
VDD
100K
100K
PROX
PROX
PROX
SYI SYO
SYI SYO
SYI SYO
E90901
E90901
Master
Slaves
E90901
Figure 9: Example for synchronization of three E90901
4.4.1. Decision of master
In a chain of E90901 there is only one master E90901. The decision of which depends on the output pin
SYO. The master E90901 is defined by a pull-up resistor of 100K on its SYO output. Initially the digital output
of this pin is tristated so the value on the pin depend on weather it is connected to a pull-up.
VDD
LOGIC
SYO_OUT
TRISTATE
100K
SYO
EN_SYO
SYO_READ
Figure 10: Decision of master
After the initial power on or a SPI-reset each E90901 checks to see if it is a master or a slave. This decision
depends on the value of SYO_READ while EN_SYO is 'LOW'. The signal EN_SYO is an enable for a tristate,
while it is 'LOW' the signal SYO_OUT is in effect disconnected from the circuit.
The value of EN_SYO is the delayed power-on or SPI reset.
ELMOS Semiconductor AG
Specification
22 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
4.4.2. Cancelling a touch signal
To avoid the case where there is a touch by two or more switches at the same time a cancel-pretouch signal
is sent over the SYO line to all switches. To ensure that the switch with the highest dynamic detects its
TOUCH event, the additional touch time with SELDELAY (see 4.3.3) should be enabled. This means a higher
dynamic causes less delay.
The first switch to detect a TOUCH sends a cancel-pretouch signal on the SYO line. Each switch in turn
cancels its PRETOUCH and send the cancel-pretouch signal to the next switch. Only the switch that originally
detected the touch can stop this pulse, so the pulse is going round for ones and afterwards all other switches
can detect another TOUCH event.
The cancel-pretouch signal is a small pulse that is sent after the measurement cycle has finished and a
TOUCH has been detected. To decide on if this signal has been sent or not, the time that SYI is zero after a
falling SYI event has occurred is measured. If this time is to short then the switch knows that a TOUCH was
detected by a neighbouring switch and when it is in state PRETOUCH it will change its state to APPROX.
4.4.3. Proximtiy detection and change of sampling rate
If in a chain of several E90901 one of the slaves detects a proximity, it can't speed up the sampling rate by
itself. Only the master chip is able to do this. So all E90901 in a synchronized chain are connected parallel to
a pullup resistor and the master chip can read the common PROX signal to change the sampling rate (see
figure 9). For correct working the parameter HOLDPROX should be set to '0' to get the internal PROX = not
STANDBY which indicates the sampling rate.
4.5. Analog parameters
The parameters HICC (High Current Compensation) and HICS (High Current Sender) can be used to set the
operating point of the HALIOS loop. Additonally a selftest can be implemented when using SPI interface. By
switching the sending current from low to high a touch should be detected. The same effect can be achieved
when switching the compensation current from high to low.
With FIXS the LED driver of the sender can be set to regulated (FIXS=0) or fixed mode (FIXS=1). FIXS=1
means that the sending LED is pulsed with a constant current. By setting FIXS=0 the sending current is
inversely controlled to the compensation current. This means if the compensation current increases the
sending current is decreased by the same relative amount. In this mode the system never saturates and can
handle a great variation in optical reflections.
With G0, G1 the gain of the amplifer is set. It should be set to value that the modulator can differ between
single one LSB changes of the DAC. The limiting factor here is the noise of the amplifier which is about
2.7nArms refered to the input.
With OSCON=0 (see 4.3.3) the system can be set into a sleep mode. If this command is sent during a
measurement phase the system waits until the measurement has finished before it stops.
ELMOS Semiconductor AG
Specification
23 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
5. ESD-Protection
AVDD
DVDD
AVSS
DVSS
Figure 11: ESD-Protection for power supply pins
AVDD
TIN
DVDD
AVDD
SYO
LEDS
LEDC
MO SI
SCK
PROX
LDB
SYI
SW TO
ENSPI
MISO
AVSS
AVSS
DVSS
Figure 12: ESD-Protection for all other signal pins
Test Method
The ESD protection circuitry is measured using MIL-STD-883C Method 3015 (Human Body Model) with the
folllowing conditions:
• VIN
=
2000 Volt
• REXT =
1500 Ohm
• CEXT =
100 pF
6. Latch up Test
200mA positive and negative pulses at room temperature according to JEDEC-17
ELMOS Semiconductor AG
Specification
24 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
7. Quality and Reliability
7.1. Qualification Flow
See ELMOS document:
Standard Qualifikations Plan QM-No.: 07PL0009.XX
8. Handling and Packaging
8.1. Handling
Devices are sensitive to damage by Electro Static Discharge (ESD) and should only be handled at an ESD
protected workstation.
8.2. Packaging
See ELMOS document QM-No: 02SP0002.XX Packaging for automatic assembly.
9. Record of Revision
CHAPTER
REASON FOR AND DESCRIPTION OF CHANGE
DATE
APPROVAL
ELMOS
REV
00
Initial release
09.10.02
3.2.3.2
01
Changed current for LEDC
11.06.03
4.2
01
Changes in the algorithm
11.06.03
4.3.3
01
Reduced parameters
11.06.03
3.2/3.5
01
Parameter adaptation
11.06.03
Intro
02
TSSOP16 package added
20.10.03
1.2.2
02
Active-mode description corrected
20.10.03
4.2.2.1
02
Active-mode description corrected
20.10.03
2.1
02
Prox-Pin-specification added
20.10.03
10.1
02
Application example updated
20.10.03
4.2.3
02
Timeout now also in PROX
24.02.04
4.3.3
02
New default for THD1/THA + add. value
24.02.04
4.3.3
02
Timeout value for PROX added
24.02.04
4.5
02
OSCON description corrected
24.02.04
ELMOS Semiconductor AG
Specification
25 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
10. Application examples
10.1. Power Supply
Care should be taken when switch-mode power supplies (SMPS) are used. When the
primary side is not correctly connected to the mains the secondary side may float with up
to 300V. This may cause malfunction of the device due to capacitive coupling from the
TIN-pin to any ground connection outside the system.
Generally the use of switch-mode power supplies is not recommended.
10.2. Application with SPI interface
Note: Pins MOSI (15), SCK (16) and in SPI-Mode TOUCHB/LDB (10) are CMOS-inputs
and should be fixed to VDD or GND when not in use. If cases where the SPI-programming
device may be disconnected pull-down resistors should be used. Please note that pins
with pulldown/pullup resistors are EMI sensitive. Layout and PCB are available on request.
Figure 13: Evaluation board with SPI-interface
ELMOS Semiconductor AG
Specification
26 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
Device Type
Footprint
Designators
Supplier
Order
code
Comment
47µF
47µF
100K
100nF
100nF
100nF
10K
1M
1M
22R
300R
330R
4104
47K
1K
100K
BCX71G
CON2
SMD ELKO
SMD ELKO
DIN45921T.404
SMD 2220 CAP
SMD 2220 CAP
SMD 2220 CAP
DIN45921T.404
DIN45921T.404
DIN45921T.404
DIN45921T.404
DIN45921T.404
DIN45921T.404
SO16
DIN45921T.404
DIN45921T.404
DIN45921T.404
SOT-23
SCC2
C1
C2
R7
C4
C5
C6
R6
R10
R11
R1
R3
R2
IC2
R4
R17,R18,R19,R20
R13,R14,R15,R16
Q1
J1
Bürklin
Bürklin
Bürklin
Bürklin
Bürklin
Bürklin
Bürklin
Bürklin
Bürklin
Bürklin
Bürklin
Bürklin
Bürklin
Bürklin
10D382
10D382
07 E788
41D4324
41D4324
41D4324
07 E692
07 E884
07 E884
07 E436
07 E544
07 E548
61S4310
07 E756
Bürklin
Conrad
DB25
DB25RA/F
J5
Conrad
Jumper 3X2
Jumper 3X2
Jumper 1X2
Jumper 1X2
Jumper 3X1
Jumper 4X2
SFH2400-FA
IDC6
IDC6
IDC2
IDC2
IDC2
IDC8
JP5
JP6
JP4
JP3
JP2
JP1
D1
Osram
SFH4205
Side-LED
D5
Osram
SFH4200
Top-LED
D6
Osram
LEDgr
LEDred
KPE-167
SMD LED
SMD LED
D2
D3
LS1
Bürklin
Bürklin
Farnell
12S9458
729949
Power
connector
741361
D-Sub
connector
connector
connector
connector
connector
connector
connector
Q62702- Photodiode
P5035
Q62702- Compensation
P5165
diode
Q62702- Sending-diode
P978
32G3110
32G3140
927-041 Loudspeaker
ELMOS Semiconductor AG
Specification
27 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
Contents
Package SOP16/TSSOP16..................................................................................................2
Pin Description.....................................................................................................................2
1. Working Principle.............................................................................................................6
1.1. Block Diagram...........................................................................................................6
1.2. Overview Basic Functions.........................................................................................6
1.2.1. Synchronization.................................................................................................7
1.2.2. Active - and Stand-by - Operation Mode............................................................7
1.2.3. Detection Algorithms..........................................................................................7
2. General Device Specification...........................................................................................8
2.1. Absolute Maximum Ratings......................................................................................8
2.2. Recommended Operating Conditions.......................................................................8
2.3. Electrostatic Discharge Sensitivity............................................................................8
3. Detailed Electrical Characteristics....................................................................................9
3.1. Receiving Path..........................................................................................................9
3.2. Transmitting Path....................................................................................................10
3.3. Internal References and Parameters......................................................................10
3.4.SPI Interface............................................................................................................11
3.4.1.SPI DC characteristics......................................................................................11
3.4.2.SPI AC characteristics......................................................................................11
3.5. Status output...........................................................................................................13
3.6. Synchronisation.......................................................................................................13
3.7. Mode selection........................................................................................................14
3.8. Supply.....................................................................................................................14
4. Functional Description....................................................................................................15
4.1. Digital integrator......................................................................................................15
4.1.1. Integrator stepsize...........................................................................................15
4.1.2. Measurement cycle..........................................................................................15
4.2. Detection-Algorithm.................................................................................................15
4.2.1. Operation modes.............................................................................................15
4.2.2. Event detection................................................................................................15
4.2.2.1. Proximity event.............................................................................................15
4.2.2.2. Touch event..................................................................................................16
4.2.2.3. Wipe event....................................................................................................16
4.2.3. Timeout............................................................................................................16
4.2.4. Reset...............................................................................................................16
4.3. SPI Interface...........................................................................................................17
4.3.1. SPI Transmission.............................................................................................17
4.3.2. MISO Line........................................................................................................17
4.3.3. Address decoding............................................................................................18
4.4. Synchronisation ......................................................................................................23
4.4.1. Decision of master...........................................................................................23
4.4.2. Cancelling a touch signal.................................................................................24
4.4.3. Proximtiy detection and change of sampling rate............................................24
4.5. Analog parameters..................................................................................................24
5. ESD-Protection...............................................................................................................25
ELMOS Semiconductor AG
Specification
28 / 29
Date:24.02.04
QM-No.:03SP0277E.02
E909.01
6.Latch up Test..................................................................................................................25
7.Quality and Reliability......................................................................................................26
7.1. Qualification Flow....................................................................................................26
8.Handling and Packaging.................................................................................................26
8.1. Handling..................................................................................................................26
8.2. Packaging...............................................................................................................26
9. Record of Revision.........................................................................................................26
10. Application examples...................................................................................................27
10.1. Application with SPI interface................................................................................27
Figures
Figure 1: Typical application
1
Figure 2: Pin-Out E909.01
2
Figure 3: SOP16 Wide Body Package 3
Figure 4: TSSOP16 Package
4
Figure 5: Block Diagramm E90901
6
Figure 6: SPI bus timing diagram
12
Figure 7: Signals and parameters
16
Figure 8: Example of a correct data transmition, command h2200 17
Figure 9: Example for synchronization of three E90901
23
Figure 10: Decision of master
23
Figure 11: ESD-Protection for power supply pins
25
Figure 12: ESD-Protection for all other signal pins
25
Figure 13: Evaluation board with SPI-interface 27
ELMOS Semiconductor AG
Specification
29 / 29
Date:24.02.04
QM-No.:03SP0277E.02