cd00147477

AN2478
Application note
STP08DP05, STP16DP05
Normal mode and error detection features
Introduction
In applications such as electronic advertising or traffic signs that use an IC to drive a matrix
of LEDs, it is very important to verify the correct functionality of each output.
STMicroelectronics has introduced the STP08DP05 and STP16DP05 featuring output error
detection. This application note shows how to utilize the devices under normal mode
operative conditions and how to perform error detection.
August 2007
Rev 3
1/21
www.st.com
Contents
AN2478
Contents
1
Device description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2
Normal mode functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3
Error detection features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4
Error detection output test circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.1
5
Proper supply LED voltage for correct error detection . . . . . . . . . . . . . . . 11
Evaluation boards with error detection features using STP08DP05 LED
drivers 13
5.1
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5.2
Timing diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5.3
STP08DP05 vs. STP08CDC596 detection diagram . . . . . . . . . . . . . . . . 15
5.4
Schematic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
5.5
Bill of materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6
Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
7
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
2/21
AN2478
List of figures
List of figures
Figure 1.
Typical application of STP08DP05 and/or STP16DP05 devices . . . . . . . . . . . . . . . . . . . . . 4
Figure 2.
Typical functionality in normal mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Figure 3.
Typical functionality without OE/DM2 signal and the output switching ON according to
LE/DM1 signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Figure 4.
Error detection sequence for STP08DP05 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Figure 5.
Error detection sequence for STP16DP05 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Figure 6.
STP08DP05 typical error detection results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Figure 7.
Entering output error detection timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Figure 8.
Resuming normal mode timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Figure 9.
Error detection sequence problem due to LE/DM1 synchronization. . . . . . . . . . . . . . . . . . 10
Figure 10. Error detection sequence problem due to OE/DM2 synchronization . . . . . . . . . . . . . . . . . 11
Figure 11. Detection circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 12. STEVAL-ILL002V3 or 4 evaluation boards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 13. Timing diagram for the STEVAL-ILL002V3 or 4 evaluation board . . . . . . . . . . . . . . . . . . . 14
Figure 14. Detection diagram for STEVAL-ILL002V3 or 4 evaluation board . . . . . . . . . . . . . . . . . . . . 15
Figure 15. Detection diagram for STP08DP05 and STP08CDC596 LED drivers . . . . . . . . . . . . . . . . 16
Figure 16. Schematic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3/21
Device description
1
AN2478
Device description
The STP08DP05 and STP16DP05 are monolithic, low voltage shift registers. The device
contains either an 8-bit (STP08DP05) or a 16-bit (STP16DP05) serial-in, parallel-out shift
register that feeds an 8-bit or 16-bit D-type storage register. Eight or sixteen regulated
currents are present in the output stage that provide 5-80 mA constant current to drive the
LEDs. The secondary device functionality (error detection) provides a status check of the
LEDs to detect any possible error during driving.
Figure 1.
4/21
Typical application of STP08DP05 and/or STP16DP05 devices
AN2478
2
Normal mode functionality
Normal mode functionality
During normal mode status, the serial data present on the SDI pin is transferred to the shift
register during the CLK rise time signal transition. After 8 CLK pulses for the STP08DP05,
or 16 CLK pulses for the STP16DP05, the data loaded on the SDI pin will be shifted to the
SDO pin with a typical delay of 15 ns (depending on the clock). This delay guarantees the
correct synchronization of the CLK and SDI signals if two or more devices are cascaded.
The data present in any register can be transferred to the respective latch when the Latch Enable (LE/DM1) is "high" (serial to parallel conversion). After this step, data is transferred
to the outputs by the output enable (OE/DM2) which turns ON the LEDs at the current set by
the external resistor. It is also possible to use the OE/DM2 pin to modify the output ON/OFF
duty cycle. This allows an optimization of dimming when two or more devices are used.
Figure 2.
Typical functionality in normal mode
The signals shown on the plot are:
●
CLK signal (CH1)
●
OE/DM2 signal (CH2)
●
Vout level (CH3)
●
OutputN (CH4) which turn ON and OFF according to the OE pulse
Under specific applicative conditions, where it is necessary to transfer data directly to the
outputs without the OE/DM2 signal (always "low"), the LE/DM1 is synchronized with a CLK
signal that transfers the shift register data to the specific output as reported in the following
plots.
5/21
Normal mode functionality
Figure 3.
6/21
AN2478
Typical functionality without OE/DM2 signal and the output switching ON
according to LE/DM1 signal
AN2478
3
Error detection features
Error detection features
This feature allows the output status detection to verify the functionality of the LEDs. The
error detection includes both open circuit detection and short circuit detection. From "normal
mode", the device is switched to "error mode" by a logic sequence on the OE/DM2 and
LE/DM1 pins. The eight data bits (STP08DP05) must be set to "1" in order to set all the
outputs ON during detection. The data are latched by LE/DM1. After latching, the outputs
are ready for the detection process. When the microcontroller switches the OE/DM2 to
"low", the device drives the LEDs in order to analyze if an open or short condition has
occurred.
In order to set the SDO output pin to the correct output error detection value, during the
acquisition time (OE/DM2 "low"), at least two CLK pulses must be applied before the rising
edge of OE/DM2 signal. These CLK pulses must be sent after the minimum detection time
(typically 500-600 ns). In this way the data loaded into the shift register will be updated
(rewritten) with the error detection data when the OE/DM2 signal turns to “high”. Good
output results are shown with a "1" logic level, and with a "0" logic level when the output is
malfunctioning (short or open condition).
The plots below show all the steps required to perform the error detection for the
STP08DP05 and the STP16DP05.
Figure 4.
Error detection sequence for STP08DP05
Feeding 8 bit of CLK signal after entering
the EDM, the SDI signal, set to 1, is
loaded inside the shift register
Set the Enable “ON”, run 2
CLK cycle minimum, wait
1micro second minimum,
then apply other 1 CLK
cycle
After the Detection
Error Windows, an
OE Signal puts the
device in Normal
Mode
LE and OE
signal for Error
Detection Mode
This signal latches the
Data vs the SDO
Detection Results shown by SDO.
In this case all the outputs are
Open
7/21
Error detection features
Figure 5.
AN2478
Error detection sequence for STP16DP05
16 CLK pulses are
required to load the
data setting 1 into
shift register
LE and OE Key
Sequence necessary
to Enter in EDM
Set the Enable "ON", run 2
CLK cycle minimum, wait
1micro second minimum,
then apply other 1 CLK cycle
The LE pulse latches
the data loaded during
the previous state
Each CLK pulse shows the
results of single Output
results:Out15;14; 13 etc.
After OE signal turns High,
the SDO pin shows the
results of Error Detection
(Open or Short in this case)
The OE Pulse switches the
device from EDM to Normal
Mode
After OE/DM2 turns to "high", the results of the outputs are synchronized with the CLK
signal rise time as shown in Table 1:
Table 1.
STP08DP05 output error detection sequence after OE acquisition
CLK Pulse after OE turn to "high" level
Output results
1° CLK Rise edge
Output7
2° CLK Rise edge
Output6
3° CLK Rise edge
Output5
4° CLK Rise edge
Output4
5° CLK Rise edge
Output3
6° CLK Rise edge
Output2
7° CLK Rise edge
Output1
8° CLK Rise edge
Output0
The same table can also be used for the STP16DP05, but in this case, 16 CLK pulses are
necessary and the results are shown following output 15, output 14, etc.
8/21
AN2478
Error detection features
Figure 6.
STP08DP05 typical error detection results
The Output results are
shown at first CLK pulse
after OE signal turns High
OUT7
OUT6
OUT0
After detection, apply an OE signal to return to normal mode. The following two figures show
the pattern necessary to enter error detection mode and return to normal mode.
Figure 7.
Entering output error detection timing
Figure 8.
Resuming normal mode timing
9/21
Error detection output test circuit
4
AN2478
Error detection output test circuit
During the error detection time, the internal structure of the device allows only an output
current test. This is done by comparing the current flowing from the output and the current
set by the programming resistor "REXT".
If the read current is typically less than 50% of the current set by "REXT", the device marks
the output as malfunctioning, and converts the previous data loaded into the shift register
from 1 to 0. These results are then transferred by the SDO pin. Table 2 shows an example of
the measured error detection threshold for several output current levels, as set by "REXT".
Table 2.
Error threshold test results
Vdd (V)
3.3
5
Iset (mA)
Measured error threshold
5
2.27
10
5.32
20
8.38
50
17.91
80
29.06
5
1.88
10
4.81
20
6.44
50
18.54
80
31.36
To correctly run the output error detection, all signals must be synchronized with the falling
edge of the CLK signal. This is necessary to avoid any setup/hold time problems. If this rule
cannot be applied due to specific application conditions (data generated by a
microcontroller, for example), it is possible to start the OE signal typically at 20 ns of delay
after the rise time of the CLK signal. The next two plots show a typical error detection mode
problem due to wrong error key (LE/DM1 or OE/DM2).
Figure 9.
Error
Detection
Problem
due to OE
signal
10/21
Error detection sequence problem due to LE/DM1 synchronization
No
detection
was
Observed
AN2478
Error detection output test circuit
Figure 10. Error detection sequence problem due to OE/DM2 synchronization
Error
Detection
Problem
due to LE
signal
No
detection
was
Observed
Only one error detection reading can be taken within the acquisition time window. If two or
more readings are required, the complete error detection sequence has to be repeated.
4.1
Proper supply LED voltage for correct error detection
For proper error detection it is necessary to set correct supply voltage for the LEDs,
otherwise a wrong LED status can be obtained from the LED drivers. During error detection
all outputs should be turned ON at least for 1 µs (LED current is set by external resistor) and
the output current and output voltage on the driver is measured in order to detect an open
load or short circuit (Figure 11). There are two detection conditions for which the supply LED
voltage must be kept in proper range:
1.
First detection condition: I OutDetect ≤0.5 • I out
If detected current is lower than 50% of current set by the external resistor, it is evaluated as
an open load or output short to ground. False error detection can occur if the LED supply
voltage is too low, because in this case the detected current is under the defined limit.
Minimum voltage for proper error detection can be calculated with the following equation:
Equation 1
V C ≥ V LEDMAX + V out
Vc: LED supply voltage [V]
VLED_MAX: maximum LED forward voltage [V]
Vout: output voltage for current set by external resistor [V]
2.
Second detection condition: V out ≥ 2.5 V
If detected voltage is higher than 2.5 V, it is evaluated as a short on LED or short to Vc.
Incorrect error detection can occur if the LED supply voltage is too high, because in this
case the detected voltage is above the defined limit. Maximum voltage for proper error
detection is calculated with the following equation:
Equation 2
V C ≤ 2.5 + V LEDMIN
11/21
Error detection output test circuit
AN2478
VLED_MIN: minimum LED forward voltage [V]
For example the STEVAL-ILL002V3 uses the OSRAM LED - LB T68C with the current set to
20 mA. The supply voltage for these LEDs was adjusted to 4.49 V, because the LED voltage
range for proper error detection is between 4.3 V and 5.5 V.
Equation 3
V c ≥ V LEDMAX + V out = 4.1 + 0.2 = 4.3 V
Equation 4
V c ≤ 2.5 + V LEDMIN = 2.5 + 3 = 5.5 V
where VLED_MAX = 4.1 V and VLED_MIN = 3 V.
Vout = 200 mV - voltage drop on the driver for 20 mA LED current (see datasheet
STP16DP05 - same voltage drop as for STP08DP05).
Figure 11. Detection circuit
Vc
LED supply
voltage
STP08DP05
Control and logic part
Iout
12/21
VLED
Vout
AN2478
Evaluation boards with error detection features using STP08DP05 LED drivers
5
Evaluation boards with error detection features using
STP08DP05 LED drivers
5.1
Description
The main aim of this section is to demonstrate two evaluation boards with error detection
features using the new STP08DP05 LED drivers: the STEVAL-ILL002V3 with OSRAM LEDs
and the STEVAL-ILL002V4 with VISHAY LEDs (Figure 12). The evaluation boards are
completely based on an existing solution already described in AN2415, because drivers
were replaced by the new STP08DP05. Therefore this section is focused on explaining only
the differences in the main features and timing diagram.
Main features of the evaluation board are:
●
Brightness regulation
●
Blinking speed regulation
●
Animated text
●
Error detection on outputs
●
PC graphic user interface for error detection(GUI)
●
DC/DC converter using the L5970D
●
Input voltage range of 7 V to 32 V
Two versions of the evaluation boards are available:
●
STEVAL-ILL002V3 using OSRAM LEDs
●
STEVAL-ILL002V4 using VISHAY LEDs
Figure 12. STEVAL-ILL002V3 or 4 evaluation boards
5.2
Timing diagram
The heart of this application is the microcontroller (ST7LITE39) which sends the data
through the SPI to the LED drivers. There are five STP08DP05 LED drivers each with eight
outputs assembled to allow independent driving of 40 LEDs during normal operational mode
and also to detect the status of incorrect LEDs during error detection mode. The
implementation method is described in the timing diagrams in this document.
13/21
Evaluation boards with error detection features using STP08DP05 LED drivers
AN2478
The timing diagram for normal operational mode is shown in Figure 13 (left side). The yellow
waveform is the clock frequency of the SPI set to 2 MHz. Five bytes are sent to the drivers in
order to independently control 40 LEDs . When all data are shifted to the drivers (registers)
the latch (red waveform) is switched to high and rewrites the storage registers. The OE pin
enables the output driver sink current. Current is modulated by the potentiometer which
changes the PWM duty cycle on the OE pin (PWM frequency is set at 244 Hz).
More information about timing diagram in normal operation mode is also written in
application note AN2141, since the new STP08DP05 is compatible with the previous
versions of the LED drivers.
Complete error detection timing diagram for checking the status of all 40 LEDs on the
STEVAL-ILL002V3 or 4 is also shown in Figure 13 (right side). Error detection mode is
divided to 5 timing intervals. The first interval allows enterance into error detection mode
through generation of a special sequence on the latch and OE pins synchronized by the
clock frequency. This sequence is described in Figure 6. When the LED drivers enter error
detection mode the high level must be sent through SPI to the outputs and then latched. In
the next step the status of incorrect LEDs is detected. An enlarged view of the third timing
interval is provided in Figure 14. The OE is set to low level for at least 1 µs (in this case 50
µs) and one clock cycle (yellow) is applied. The status of the LEDs is obtained when OE is
turned to high level as shown in the fourth timing interval (the detection result is read on the
SDO on the falling edge of the SPI clock). First, the data are read from the last driver E, then
from D, etc. To demonstrate the error detection feature the LED diode 39 (see the schematic
diagram in Figure 16) was shorted and therefore the results coming from the LED drivers
are the following:
●
DRIVER A: 1111 1111
●
DRIVER B: 1111 1111
●
DRIVER C: 1111 1111
●
DRIVER D: 1111 1111
●
DRIVER E: 1011 1111 (output 6 faults)
As soon as the status of all LEDs is checked the LED drivers should return to the normal
operational mode by generating a special sequence during fifth timing interval. The timing
diagram for resuming normal mode is also shown in Figure 7.
Figure 13. Timing diagram for the STEVAL-ILL002V3 or 4 evaluation board
1
2
3
4
E
D
C
5
B
A
CLK
SDO
LE
Normal
mode
Error detection mode
OE
Zoom
14/21
AN2478
Evaluation boards with error detection features using STP08DP05 LED drivers
Figure 14. Detection diagram for STEVAL-ILL002V3 or 4 evaluation board
Driver E
CLK
SDO
Output 6 fault detected
LE
OE
5.3
STP08DP05 vs. STP08CDC596 detection diagram
Figure 15 shows the detection diagram for the STP08DP05 and STP08CDC596 LED
drivers.
When the OE pin is "0" the LED drivers check the status of the LEDs. After this the output
data (SDO) are read on the falling edge of the clock SPI. The resulting output bits are not
the same for both drivers, as shown in the red frames in Figure 15. The seventh bit is read
like the first for the STP08DP05, but for the STP08CDC596 the sixth bit is read. Therefore if
both drivers are used in the application the LED status obtained from the drivers must be
corrected by the SW, otherwise an erroneous status is detected (shifted by one bit).
15/21
Evaluation boards with error detection features using STP08DP05 LED drivers
AN2478
Figure 15. Detection diagram for STP08DP05 and STP08CDC596 LED drivers
STP08DP05 – detection diagram
SDO reading when
the OE pin is turned to “1”
SDO reading when
STP08CDC596 – detection diagram the OE pin is turned to “1”
16/21
10nF
C13
RES
SD0
SW1
TDO
10nF
C16
10k
R9
VCC
10nF
C14
VCC
VCC
SW2
10k
R8
RES
1
2
3
J5 CON3
1
2
3
4
5
6
7
8
SMAJ33A-TR
D44
10uF/35V
C19
U1
16
15
14
13
12
11
10
9
220pF
C20
4k7
R10
22nF
C18
6
8
2
4
5
1
VIN
U7
IO5 L5970D
100nF
8
D12
U2
1
VOUT
LE50/SO
2
1
2K2
R12
6k8
JUMPER JP2
1K3
360
U3
C9
+
C8
470nF
220uF/25V
C21
1k3
470nF
C10
D24
R5
VCC
D23
470nF
100uF/16V
C22
16
15
14
13
12
11
10
9
D22
D21
GND Vdd
SDI R-EXT
CLK SDO
/LE
/OE
5
12
6
11
7
10
8
9
D20
GREEN LED
D42
560
R14
100nF
C5
STP08DP05/C
1
2
3
4
5
6
7
8
D19
D18
D17
2.2uF
C1
VCC
R13
100nF
C15
D16
R4
VCC
D15
R11
33uH
STPS340U
D41
L1
16
15
14
13
12
11
10
9
D14
D13
GND Vdd
SDI R-EXT
CLK SDO
/LE
/OE
5
12
6
11
7
10
8
9
STP08DP05/B
1
2
3
4
5
6
7
8
D11
D9 D10
C17
1k3
R3
D5 D6 D7 D8
GND Vdd
SDI R-EXT
CLK SDO
/LE
/OE
5
12
6
11
7
10
8
9
STP08DP05/A
D1 D2 D3 D4
SW PUSHBUTTON
J1
SW PUSHBUTTON
ICP
RDI
20
19
18
17
16
15
14
13
12
11
U8
ST7lite3
1
2
3
4
5
6
7
8
9
10
INPUT VOLTAGE
FROM 7V UP TO 32V
10k
2
R1
VCC
10k
R2
2
VCC
10uF
+
C2
1
3
1
3
1 2
3 4
5 6
7 8
9 10
C4
GND
2
VCC
3
7
100nF
GND
3
VCC
GND
6
100nF
GND
7
2
1
C3
INHIB
5
1
2
3
4
5
6
7
8
U4
U6
16
15
14
13
12
11
10
9
VCC
Size
B
Title
ST232ABN
C1+
Vdd
V+
GND
C1T1OUT
C2+
R1IN
C2R1OUT
VT1IN
T2OUT T2IN
R2IN R2OUT
470nF
C11
16
15
14
13
12
11
10
9
RxD
TDO
RDI
2.2uF
C12
1k3
P1
16
15
14
13
12
11
10
9
R7
SD0
1k3
Rev
<RevCode>
D40
JP1
JUMPER
VCC
D39
D38
D37
CONNECTOR DB9
5
9
4
8
3
7
2
6
1
U5
GND Vdd
SDI R-EXT
CLK SDO
/LE
/OE
5
12
6
11
7
10
8
9
D36
D35
D34
D33
1
2
3
4
5
6
7
8
STP08DP05/E
100nF
C7
Document Number
STEVAL-ILL002V3 (OSRAM LEDs)
<Doc>
STEVAL-ILL002V4 (VISHAY LEDs)
Diagnostic LED Driver
TxD
D32
R6
VCC
D31
D30
D29
GND Vdd
SDI R-EXT
CLK SDO
/LE
/OE
5
12
6
11
7
10
8
9
D28
D27
D26
D25
1
2
3
4
5
6
7
8
STP08DP05/D
100nF
C6
2
5.4
1
AN2478
Evaluation boards with error detection features using STP08DP05 LED drivers
Schematic diagram
Figure 16. Schematic diagram
17/21
Evaluation boards with error detection features using STP08DP05 LED drivers
5.5
Bill of materials
Table 3.
Bill of materials
Item Qty
Reference
Part
Description
1
2
C1,C12
2.2 µF/50 V
Electrolytic capacitor
2
1
C2
10 µF/35 V
Electrolytic capacitor
3
7
C3,C4,C5,
C6,C7,C15,
C17
100 nF/50 V
Ceramic capacitor SMD
0805
4
4
C8,C9,C10,
C11
470 nF/16 V
Ceramic capacitor SMD
0805
5a
2
C14,C16
10 nF/50 V
Ceramic capacitor SMD
0805
5b
1
C13
10 nF/50 V
Ceramic capacitor SMD
1206
6
1
C18
22 nF/50 V
Ceramic capacitor SMD
0805
7
1
C19
10 µF/35 V
Tantal capacitor
8
1
C20
220 pF/50 V
Ceramic capacitor SMD
0805
9
1
C21
220 µF/25 V
Electrolytic capacitor
10
1
C22
100 µF/16 V
Tantal capacitor
11
40
D1,D2,D3,
D4,D5,D6,
D7,D8,
D9,D10,
D11,D12,
D13,D14,
D15,D16,
D17,D18,
D19,D20,
D21,D22,
D23,D24,
D25,D26,
D27,D28,
D29,D30,
D31,D32,
D33,D34,
D35,D36,
D37,D38,
D39,D40
LED
OSRAM SMD BLUE LED
LB T68C-P2S1-35 OR
VISHAY SMD GREEN
LED
VLMTG31N2S1 - GS08
12
1
D41
STPS340U
Diode
13
1
D42
GREEN LED
SMD LED 1206
14
1
D44
SMAJ33A-TR
Transil
18/21
Order code
AN2478
Supplier
OSRAM
OR VISHAY
STPS340U
STMicroelectronics
SMAJ33A-TR
STMicroelectronics
AN2478
Table 3.
Item Qty
Evaluation boards with error detection features using STP08DP05 LED drivers
Bill of materials (continued)
Reference
Part
Description
Order code
Supplier
L5970D
STMicroelectronics
DO3316P-333ML
COILCRAFT
15
1
IO5
L5970D
DC/DC converter
16
2
JP1,JP2
JUMPER
Jumpers + switches
17
1
J1
ICP
Programming connector
18
1
J5
CON3
Input connector
19
1
L1
33 µH
Inductor
20
1
P1
CONNECTOR DB9
CAN connector - 9 pins
21a
2
R1,R2
10 k
Potenciometers with axis
21b
2
R8,R9
10 k
SMD resistors 0805
22
5
R3,R4,R5,
R6,R7
1k3
SMD resistors 1206
23
1
R10
4k7
SMD resistors 0805
24
1
R11
6k8
SMD resistors 1206
25
1
R12
2K2
SMD resistors 1206
26
1
R13
360
SMD resistors 1206
27
1
R14
560
SMD resistors 1206
28
2
SW1,SW2
SW PUSHBUTTON
Switch
29
5
U1,U2,U3,
U4,U5
STP08DP05
LED drivers
STP08DP05TTR
STMicroelectronics
30
1
U6
ST232ABN
RS232 driver
ST232ABD
STMicroelectronics
31
1
U7
LE50/SO
Linear voltage regulator
LE50ABD
STMicroelectronics
32
1
U8
ST7lite3
Microcontroller
ST7FLITE39F2M6 STMicroelectronics
19/21
Conclusion
6
AN2478
Conclusion
The new features of STP08DP05 and STP16DP05 allow improved control of the application.
The full detection test enables the device to provide feedback to the microcontroller, and the
feedback of the error detection can be managed locally or remotely.
7
Revision history
Table 4.
20/21
Document revision history
Date
Revision
Changes
07-Mar-2007
1
Initial release
22-May-2007
2
Minor text changes
31-Aug-2007
3
– From Section 4.1 to Section 5.5 added
– Chapter 6 modified
AN2478
Please Read Carefully:
Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the
right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any
time, without notice.
All ST products are sold pursuant to ST’s terms and conditions of sale.
Purchasers are solely responsible for the choice, selection and use of the ST products and services described herein, and ST assumes no
liability whatsoever relating to the choice, selection or use of the ST products and services described herein.
No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted under this document. If any part of this
document refers to any third party products or services it shall not be deemed a license grant by ST for the use of such third party products
or services, or any intellectual property contained therein or considered as a warranty covering the use in any manner whatsoever of such
third party products or services or any intellectual property contained therein.
UNLESS OTHERWISE SET FORTH IN ST’S TERMS AND CONDITIONS OF SALE ST DISCLAIMS ANY EXPRESS OR IMPLIED
WARRANTY WITH RESPECT TO THE USE AND/OR SALE OF ST PRODUCTS INCLUDING WITHOUT LIMITATION IMPLIED
WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER THE LAWS
OF ANY JURISDICTION), OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY RIGHT.
UNLESS EXPRESSLY APPROVED IN WRITING BY AN AUTHORIZED ST REPRESENTATIVE, ST PRODUCTS ARE NOT
RECOMMENDED, AUTHORIZED OR WARRANTED FOR USE IN MILITARY, AIR CRAFT, SPACE, LIFE SAVING, OR LIFE SUSTAINING
APPLICATIONS, NOR IN PRODUCTS OR SYSTEMS WHERE FAILURE OR MALFUNCTION MAY RESULT IN PERSONAL INJURY,
DEATH, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE. ST PRODUCTS WHICH ARE NOT SPECIFIED AS "AUTOMOTIVE
GRADE" MAY ONLY BE USED IN AUTOMOTIVE APPLICATIONS AT USER’S OWN RISK.
Resale of ST products with provisions different from the statements and/or technical features set forth in this document shall immediately void
any warranty granted by ST for the ST product or service described herein and shall not create or extend in any manner whatsoever, any
liability of ST.
ST and the ST logo are trademarks or registered trademarks of ST in various countries.
Information in this document supersedes and replaces all information previously supplied.
The ST logo is a registered trademark of STMicroelectronics. All other names are the property of their respective owners.
© 2007 STMicroelectronics - All rights reserved
STMicroelectronics group of companies
Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America
www.st.com
21/21
Similar pages