Programming Software Manual for MLX71122 RF Receiver DownloadLink 5208

SW71122
Programming Software Manual
Receiver MLX71122
MLX71122 RF Receiver
Programming Software Manual
Software Version v3.1
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Software Revision History
Software Revision
v2.0
v2.1
v3.1
39011 71122 01
Rev. 003
Date
Changes
28.08.2006 Initial Version for MLX71122A
001
nd
002
nd
003
03.01.2007 Adaptation of software to 2 version of MLX71122A
10.04.2008 Adaptation of software to 2 version of MLX71122B
Page 1 of 20
Doc. Rev.
SW71122-Manual
April/08
SW71122
Programming Software Manual
Receiver MLX71122
Content
1
General Description ...................................................................................................4
2
Hardware and Software Requirements.....................................................................5
3
Installation and Files..................................................................................................5
4
Using the Software.....................................................................................................6
4.1
Software Start Up ................................................................................................................ 6
4.2
Menus.................................................................................................................................. 7
4.2.1
4.2.2
4.2.3
4.2.4
5
File............................................................................................................................................ 7
LPT ........................................................................................................................................... 7
Settings .................................................................................................................................... 7
About ........................................................................................................................................ 7
4.3
Send to IC - Button .............................................................................................................. 8
4.4
Tuning Info - Frame ............................................................................................................. 8
4.5
Program Status Line............................................................................................................ 8
4.6
IC Status - Frame ................................................................................................................ 9
4.7
Frequency Pre-Selection - Frame ....................................................................................... 9
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Description of the Control Tabs..............................................................................10
5.1
Mode Control – Tab........................................................................................................... 10
5.1.1
5.1.2
5.1.3
5.1.4
5.1.5
5.1.6
5.2
Gain Control – Tab ............................................................................................................ 12
5.2.1
5.2.2
5.2.3
5.2.4
5.2.5
5.2.6
5.2.7
5.2.8
5.2.9
5.3
Operation Mode...................................................................................................................... 10
Multi Functional Output Mode ................................................................................................ 11
Function of LDRSSIL bit......................................................................................................... 11
Bit Slicer Mode ....................................................................................................................... 11
DTAO Polarity ........................................................................................................................ 11
Demodulation Type ................................................................................................................ 11
LNA......................................................................................................................................... 12
IF Filter ................................................................................................................................... 12
1st Mixer Gain ......................................................................................................................... 12
2nd Mixer Gain ........................................................................................................................ 13
Demodulator Gain .................................................................................................................. 13
RSSI Gain .............................................................................................................................. 13
Enable AGC ........................................................................................................................... 13
Delay Settings ........................................................................................................................ 13
Delay Mode ............................................................................................................................ 13
PLL Control – Tab ............................................................................................................. 14
5.3.1
5.3.2
5.3.3
5.3.4
5.3.5
5.3.6
LDTIME .................................................................................................................................. 14
LDMODE ................................................................................................................................ 14
LDERR ................................................................................................................................... 14
CPCUR................................................................................................................................... 15
ROCUR .................................................................................................................................. 15
PRESCUR.............................................................................................................................. 15
39011 71122 01
Rev. 003
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Programming Software Manual
Receiver MLX71122
5.3.7
5.3.8
5.3.9
5.3.10
5.4
Frequency and IFF Control – Tab ..................................................................................... 16
5.4.1
5.4.2
5.4.3
5.4.4
5.4.5
5.4.6
5.4.7
5.4.8
5.4.9
5.4.10
5.4.11
5.4.12
5.4.13
5.4.14
5.4.15
5.5
PFDPOL ................................................................................................................................. 15
VCO Range ............................................................................................................................ 15
VCO Buffer Current ................................................................................................................ 15
VCO Core Current.................................................................................................................. 15
Auto Adjustment ..................................................................................................................... 16
Halt ......................................................................................................................................... 16
RIFF Divider ........................................................................................................................... 16
IFF Preset Value .................................................................................................................... 17
IFF centre freq........................................................................................................................ 17
fXTAL ......................................................................................................................................... 17
R Divider................................................................................................................................. 17
fRF ........................................................................................................................................... 17
A ............................................................................................................................................. 17
N ............................................................................................................................................. 17
NTOT ........................................................................................................................................ 17
Calculate Button ..................................................................................................................... 17
LO1......................................................................................................................................... 18
LO2......................................................................................................................................... 18
LO2DIV................................................................................................................................... 18
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Register Set - Tab ............................................................................................................. 18
39011 71122 01
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Programming Software Manual
Receiver MLX71122
1
General Description
The PC programming software can be used to control the operational modes of the MLX71122 RF receiver
at its Serial Programming Interface (SPI) through the three pins A/SCLK, B/SDTA and C/SDEN. The pin
SPISEL must be at logic HIGH in order to set the MLX71122 to SPI mode. Otherwise the receiver operates
in stand-alone (or ABC) mode and cannot be programmed via the three pins A/SCLK, B/SDTA and C/SDEN.
In SPI mode, it is possible to write in and read out the seven control registers R0 to R6. Register R7 is a
read-only register for status information. In ABC mode, 8 predefined frequency channels between 369.5
MHz and 395.9 MHz can be selected by parallel programming at the three pins A/SCLK, B/SDTA and
C/SDEN.
28
200k
DF2
9
DF1
8
MODSEL
6
RSSI
5
MIXP
4
MIXN
3
VEEIF
2
LNAO
VEELNA
1
VCCANA
A block diagram of the receiver is shown below.
OA1
ASK
MIX2
LO1
FSK
IFF
IF2
IFA
LO2
SLCSEL
PDN
16
20
21
30
VEEANA
10
VEEDIG
19
ENRX
18
OA2
26
DTAO
22
SLC
RBIAS
17
SW2
BIAS
A/SCLK
7
B/SDTA
24
C/SDEN
RO
SPISEL
23
Control
Logic
ROI
CP
MFO
TNK1 12 13 TNK2 15
LF
LF
VCCVCO
PKDET_
1M
R
counter
PFD
VCO
VEEVCO
25
PDP
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N/A
counter
14
27
PKDET+
FSK
DEMOD
LO2DIV
11
DFO
SW1
1M
IF1
VCCDIG
31
LNA
200k
MIX1
LNAI
29
200k
32
The following tables show the functionality of the three digital control pins that are used for general operating
mode selection.
Pin
SPISEL
Pin
Value
0
MODSEL
1
0
ENRX
1
39011 71122 01
Rev. 003
Value
Function
0
ABC mode - stand-alone mode, 8 pre-defined frequencies
1
SPI mode - programmable mode, full control via SPI
SPISEL
Function
0
FSK receive mode
1
no effect
0
ASK receive mode
1
no effect
0
Receiver in shutdown mode
1
Receiver in last programmed operational mode
0
Receiver in receive mode
1
Receiver in receive mode
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Programming Software Manual
Receiver MLX71122
2
Hardware and Software Requirements
The MLX71122 program is written for PC hardware that has 32-bit Microsoft Windows™ installed. It runs
under Windows 95/98/2000 and Windows XP. The program uses TVicPort I/O driver to interface to the
parallel port. We recommend the use of Windows 2000™ or later system versions.
The computer’s parallel printer port (LPT) is used to send signals to the IC and to read data from the IC. Port
addresses 0x278, 0x378 and 0x3BC (hexadecimal) are supported.
The following LPT ports can be connected with the corresponding IC pins:
LPT port
Direction
IC pin
Cable pin
BUSY (pin11)
←
MFO (pin 23)
Connected (1)
GND (pin18-25)
⎯
GND
Connected (2)
D1 (pin3)
→
A/SCLK (pin 19)
Connected (3)
D2 (pin4)
→
B/SDTA (pin 18)
Connected (4)
D0 (pin2)
→
C/SDEN (pin17)
Connected (5)
A programming cable with male 25-pole SUB-D connector is available on request or can be purchased together with the evaluation board EVB71122. Note that pin 7 of the MLX71122 (SPISEL) is connected to logic
HIGH on the EVB71122. This is to set the receiver to SPI mode.
3
Installation and Files
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The installation program will ask you for a folder where you want to install the files. By default, the program
installs the software in the directory:
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C:\Program Files\Melexis\MLX71122_V31
The Following files will be installed:
File
Function
MLX71122_V31.exe
Main program executable
unins000.exe
Program to uninstall the software
unins000.dat
Uninstall data file
MLX71122.ini
Init file for windows start of main program
TVicPort.dll
Dynamic library to support port programming
ReadMe.txt
ReadMe file
We recommend creating the icon of the main program on your PC’s desktop to easily access the program.
The working directory folder of the link should be set to the installation folder.
Copyrights:
TVicPort I/O driver, © En Tech Taiwan
Windows 95/98/2000 and Windows XP, © Microsoft Corporation.
39011 71122 01
Rev. 003
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Programming Software Manual
Receiver MLX71122
4
Using the Software
4.1
Software Start Up
The software can be started by double clicking on the main program icon in the installation directory or by
double clicking on the link. During start-up the software reads out the corresponding init-file and restores all
settings that were active when the software was regularly closed the last time.
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A typical first menu view of the program is shown in the figure above. The program starts up with the tab
Mode Control activated.
Data is only sent to the IC if the Send to IC button is pressed or Send always is activated.
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4.2
4.2.1
Menus
File
The menu file contains three menu items:
•
•
•
Load Config
Save Config
Exit
load a previously defined config-file and activate the new state
save the actual state in a new config-file
close the program and save the state into the init-file
The Exit field in the window frame has the same function as the Exit menu item. After a configuration is
loaded its file name is displayed in the window title as reminder.
4.2.2
LPT
This menu enables the user to choose a LPT port address to use for the programming. Three port addresses are supported (in hexadecimal):
•
•
•
0x278
0x378
0x3BC
(default)
The port address is displayed in the Program Status Line at the lower-right corner of the program window.
4.2.3
Settings
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The Defaults menu item of this menu restores the state that is hard-coded on the IC and that is active after
powering up the IC. The default receive frequency is 384MHz. After recovering the default settings the text
Default Settings is displayed in the window title as reminder.
4.2.4
About
This menu displays a window with information about the LPT-port to pin connections.
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Receiver MLX71122
4.3
Send to IC - Button
After pressing the Send to IC button the registers R0 to R6 of the IC will be programmed with the data from
the actual state.
If the checkbox Send always is activated this operation is performed every time a control field is changed.
This can be used to simplify monitoring of single setting changes but it can produce unwanted intermediate
states if more than one setting has to be changed.
4.4
Tuning Info - Frame
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The values of seven important frequencies are displayed in the tuning info frame:
•
•
•
•
•
•
•
fRF:
fCH:
fIF1:
fIF2:
fLO1:
fLO2:
fPFD:
actual receive frequency
channel step width
first intermediate frequency after the first mixer
second intermediate frequency after the second mixer
VCO output frequency or LO input frequency of first mixer
LO input frequency of second mixer (depends on fLO1)
working frequency of the phase-frequency detector of the PLL
All frequencies are given in MHz with three post decimal positions.
4.5
Program Status Line
The Status Line at the bottom of the program window displays three status values. The name of the actual
tab field is shown on the left hand side. The middle part displays the selected operation mode and the output
mode of the MFO pin separated by a vertical bar. On the right hand side the actual LPT port address is
shown.
39011 71122 01
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Receiver MLX71122
4.6
IC Status - Frame
The IC Status frame displays information about the internal state of the IC if the Multi Functional Output
(MFO) mode is set to SPI out (left figure). A click on the Refresh button reads out the data from the MFO-pin
of the IC.
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The following data is displayed:
Field
IFFVAL
IFFSTATE
LD
RSSI
LD Time
Value
Integer number between 0 and 255
tuned
tune up
tune dn
CCO fail
locked
Not locked
Low
In range
High
Time in ms
Meaning
Tuning value of the internal IF filter
Filter tuned or auto-tuning disabled
Tuning up the filter frequency
Tuning down the filter frequency
Master oscillator of filter does not work
PLL locked in
PLL not locked in
VRSSI in lower region
VRSSI in mid region
VRSSI in upper region
Approximate PLL lock time
LD is only displayed if Lock Detect is selected in function of LDRSSIL bit or MFO-mode is set to
LD-out. In LD-out mode the additional field LD Time is displayed (right figure) and the PLL lock in time is
measured every time when data is send to the IC.
4.7
Frequency Pre-Selection - Frame
Four fixed receive frequencies at 315.0MHz, 433.9MHz, 868.3MHz or 915.0MHz can be pre-selected to
ease the initialization of the receiver. All settings of the receiver are affected and are reset to their default
value with respect to the receive frequency.
39011 71122 01
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Receiver MLX71122
5
Description of the Control Tabs
The user can select five tabs for different control settings of the SPI-mode.
5.1
Mode Control – Tab
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The Mode Control tab displays all dialog fields that are used to change the operating modes of the circuit.
On top are the controls for the Operation Mode and the mode of the Multi Functional Output (MFO).
5.1.1
Operation Mode
Selections are:
•
•
•
•
Shutdown
Receive
RO and bias only
Synthesizer only
all blocks deactivated, only SPI active (default)
receiving data from LNAI at selected frequency
only biasing system and reference oscillator are working
only biasing system, reference oscillator and PLL are working
The first operation mode consumes virtually no current. The circuit is dead except of the SPI that can listen
to commands. In Receive mode all necessary blocks are turned on to receive data at the programmed
frequency.
The last two operation modes can be used to accelerate the start-up of the circuit after periods of silence.
With RO and biasing only, the long start-up time of the reference oscillator (RO) can be circumvented. RO
and biasing consume not as much current as the whole receiver. With Synthesizer only the full PLL is
already working and locked in. Current consuming blocks as the LNA, the IF-filter and the FSK-demodulator
are turned off in this state. The last mode is useful if the receiver has to listen in short periods.
39011 71122 01
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Receiver MLX71122
5.1.2
Multi Functional Output Mode
Selections are:
•
•
•
•
•
•
•
Z-State
SPI-out
Logic-0
Logic-1
RO-out
IF-out
LD-out
MFO pin is in high impedance mode
MFO pin is digital serial output for data of register R7 (default)
MFO pin is pulled to ground
MFO pin is pulled to VCC
MFO pin is buffered, analogue output of RO frequency
MFO pin is buffered, analogue output of IF2 signal after the IF-filter
MFO pin represents lock state of PLL
All other visible selections are only for test purposes and have no significant value if the circuit is operating
on the evaluation board.
Z-State, Logic-0 and Logic-1 can be used to control an additional digital input on the board if no microcontroller output is available. With RO-out a 10MHz clock frequency is available on the board that can also be
used to save one quartz crystal by driving the RO of another MLX71122 receiver. IF-out provides the internal
IF2 signal amplified by a factor of 5 if the MFO-pin is unloaded. The output resistance is about 610Ω in this
mode. The IF-out mode can be used to further filter the IF2 signal. In this case an external limiting amplifier
and demodulator must be used.
With LD-out the state of the PLL can be detected. The lock state is also displayed in the LD field of the IC
Status frame. An additional field in the IC Status frame appears that can display the approximate lock in
time in ms measured by the PC. This is not very accurate!
In SPI-out mode the data of register R7 can be read out and the different circuit states are displayed in the
IC Status frame.
5.1.3
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Function of LDRSSIL bit
Unfortunately there is more information available than bits in R7. So, these radio buttons select the output
that is multiplexed to bit 11 of register R7. One can either select the output of the RSSI low flag or the Lock
Detection flag (default) of the PLL. The selection affects the output displayed in the IC Status frame.
5.1.4
Bit Slicer Mode
These radio buttons control which data slice mode is used. One can either select averaging mode (default)
that uses a RC-low pass to generate the reference voltage or peak detector mode that uses the median as
reference for the output comparator.
5.1.5
DTAO Polarity
At positive polarity (default) the DTAO output is high if the DFO voltage is higher than the reference voltage
and vice versa.
5.1.6
Demodulation Type
This selects the type of demodulator to use. In case of ASK demodulation the FSK demodulator is turned off
and the RSSI pin is internally connected to the data filter. In FSK mode (default) the FSK demodulator output
is connected to the data filter but the RSSI voltage is still available at the RSSI pin.
39011 71122 01
Rev. 003
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Receiver MLX71122
5.2
Gain Control – Tab
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The Gain Control tab is split up into an upper part defining the static gain of different receiver blocks and a
lower part for controlling the Automatic Gain Control (AGC).
The frame Receiver Gain Settings contains the following controls:
5.2.1
LNA
Four different LNA gain settings are possible. Since the absolute gain depends on the input matching of the
LNA and on the quality factor of the tank circuit, only settings relative to the default gain are selectable. The
gain is controlled by the core current of the LNA.
Possible selections are: Default -20dB, Default -6dB, Default -2dB, Default
5.2.2
IF Filter
The Intermediate Frequency Filter (IFF) has four gain settings: -14dB, -6dB, 0dB (default), +6dB.
These are absolute voltage gains from the filter input to the input of the Intermediate Frequency Amplifier
(IFA). Default gain is +6dB. If MFO is set to IF-out, 14dB have to be added for the gain from the filter input to
the unloaded MFO-pin and -9dB have to be added for the gain from the filter input to the MFO-pin with 50Ω
load. The output resistance of the MFO-buffer is about 610Ω.
5.2.3
1st Mixer Gain
These radio buttons set the MIX1GAIN bit. It specifies the gain of the 1st mixer.
Possible selections are: 0dB, +14dB (default)
39011 71122 01
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5.2.4
2nd Mixer Gain
These radio buttons set the MIX2GAIN bit. It specifies the gain of the 2nd mixer.
Possible selections are: -2dB, +9dB (default)
5.2.5
Demodulator Gain
These radio buttons control the frequency to voltage conversion gain of the FSK-demodulator:
•
•
low
high
12mV/kHz (default)
14.5mV/kHz
The Automatic Gain Control (AGC) enables the circuit to keep its internal voltage amplitude levels in the
linear operation range of the different front end blocks. By default the gain settings are high to keep the noise
contribution of the active IF-filter as low as possible. If the input signal increases the filter will soon become
nonlinear because the input level is too high. A digital control circuit of the MLX71122 can be used to lower
the gains of the previous blocks to maintain the linear input range of the IF-filter as far as possible. First the
gain of mixer 2 is lowered, then mixer 1 and in the end the LNA gain.
5.2.6
RSSI Gain
The RSSIGAIN setting determines the RSSI gain of the IFA:
•
•
low
high
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39mV/dB
51mV/dB (default)
The output voltage range of the RSSI voltage will also be affected by this setting.
5.2.7
Enable AGC
This checkbox enables or disables (default) the AGC feature. Make sure that RSSIGAIN is high to use AGC.
5.2.8
Delay Settings
The AGC circuit uses the RSSIL and RSSIH flags to specify whether the gains have to be increased or
decreased. In order to make the gain switching independent of short signal fluctuations, four delay times are
selectable that specify how long the RSSIL or RSSIH flags have to be set before the gains are changed. The
delays are related to the reference frequency of the IF-filter adjustment circuit fIFF. If the reference oscillator
frequency is 10MHz then fIFF should be equal to 3MHz.
•
•
5.2.9
Selectable delays are
or for 10 MHz RO frequency
0 / fIFF (default), 3 / fIFF, 15 / fIFF, 31 / fIFF
0μs (default), 1μs, 5μs, 10.3μs
Delay Mode
These radio buttons specify whether the delay is only applied at gain increase and not at decrease (default),
or for both, increase and decrease.
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5.3
PLL Control – Tab
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The PLL Control tab contains settings for the PLL and the VCO.
5.3.1
LDTIME
This selection box specifies the minimum time delay before a lock in of the PLL occurs after start of the PLL.
It is related to the reference frequency fR of the PFD.
Four possible time delays are selectable: 2 / fR, 4 / fR, 8 / fR, 16 / fR (default)
5.3.2
LDMODE
These radio buttons specify whether the lock in condition is always checked (default) or only until the first
lock in. The repetition of the check is performed with the period set in LDERR.
5.3.3
LDERR
These radio buttons specify how long the up and down pulses of the PFD can be different without loosing
the lock in state. If the PLL is locked in, these times of different up and down signals should be very small
since there is no correction of the VCO frequency necessary. If not, the power of the reference spurs in the
VCO output signal will increase. This can be the case for leaky capacitors in the loop filter. If the default for
LDERR of 15ns is not sufficient to keep the lock in state, it can be increased to 30ns.
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5.3.4
CPCUR
This selection box specifies the charge pump current which is important to know for the design of the PLL
loop-filter. The charge pump is controlled by a Phase-Frequency-Detector (PFD) that makes it possible to
control phase as well as frequency deviations of the VCO. Four different settings are selectable:
•
•
•
•
5.3.5
100μA
400μA
400μA Dn
400μA Up
±100μA (default)
±400μA
drains 400μA from pin LF to ground; static down
sources 400μA from VCC to pin LF; static up
ROCUR
This selection box sets the core current of the reference oscillator. It should not be changed unless there is a
reason to do it.
Four current selections are available: 85μA, 170μA, 270μA, 355μA (default)
5.3.6
PRESCUR
The PRESCUR radio buttons specify the bias current of the PLL prescaler. The prescaler is a block that
works at the highest operating frequency of the circuit since it divides the VCO output signal. At high VCO
frequencies and under certain ambient conditions it may be necessary to increase its bias current from the
20μA (default) to 30μA to keep it dividing correctly.
5.3.7
PFDPOL
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The polarity of the PDF should not be changed if the standard test circuit is used where only a tank inductor
is placed between pins TNK1 and TNK2. Default value is negative. If the loop filter voltage to frequency
characteristic changes the sign of its slope, then it is necessary to change the PDF polarity. This can be the
case if an external VCO is used or if an additional element with controllable reactance is connected between
the pins TNK1 and TNK2.
5.3.8
VCO Range
The MLX71122 is designed for VCC = 5V so the default value of this setting is 5V. Nevertheless, it can be
used down to 3V if this value is set to 3V. The most critical part at lower supply voltages is the VCO range
which can be adjusted with this setting. For supply voltages in between, the optimal setting must be found by
experiment.
5.3.9
VCO Buffer Current
The output buffer of the VCO works at the highest operating frequency of the circuit. Since it has to drive the
prescaler with a digital signal, the core current of the buffer can be increased from about 900μA (default) to
1040μA if it is necessary at high VCO frequencies and under certain ambient conditions.
5.3.10
VCO Core Current
The VCO core works at the highest operating frequency of the circuit. Its core current can be increased from
about 450μA (default) to 520μA if it is necessary at high VCO frequencies and under certain ambient
conditions.
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5.4
Frequency and IFF Control – Tab
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The Frequency and IFF Control tab contains settings for the IF-filter auto-adjustment circuit and for the
control of the receive frequency.
The IF-Filter Auto-Adjustment Control uses a digitally controlled oscillator that works like a digital PLL. Its
reference frequency, which is by default at about 3MHz, is derived from the RO frequency by dividing fRO by
RIFF Divider and multiplying it by 200. The digital control word of the filter oscillator also controls the centre
frequency of the filter (2MHz). This is possible because it uses the same transconductance cells as the oscillator. The tab offers several fields to control the adjustment circuit.
5.4.1
Auto Adjustment
This checkbox controls whether the auto-adjustment is turned on or off. If it is turned on (default), it corrects
continuously the centre frequency of the filter. If it is turned off, then the actual IFF Preset Value is loaded
into the digital control word and the auto-tuning stops with this value. The filter works with this IFF Preset
Value if auto-adjustment is deactivated and the IFFSTATE (see section 4.6) changes to tuned. After enabling the auto-tuning again the process starts with the previously loaded IFF Preset Value.
5.4.2
Halt
This checkbox interrupts the auto-tuning process but leaves the last control value in the internal register.
After deactivating this box the tuning process continues with this value.
5.4.3
RIFF Divider
This value controls the ratio of the IF filter oscillator frequency to the RO frequency. Default value is 684.
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5.4.4
IFF Preset Value
This value is the start value of the digitally controlled filter oscillator. It is loaded into the internal control word
register after start-up or if the auto-tuning is deactivated. Default value is 91.
5.4.5
IFF centre freq.
This field displays the actual centre frequency of the filter with respect to all settings. It should be 2MHz
because it is the IF2. Also slightly different IF-frequencies are possible in order to correct frequency deviations caused by an inappropriate channel step width.
5.4.6
fXTAL
This is the oscillator frequency of the quartz crystal oscillator. The IC is designed for a fXTAL of 10MHz!
5.4.7
R Divider
This is the reference divider value by that the RO frequency is divided to provide the reference frequency for
the PFD. Default value is 75.
5.4.8
fRF
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It is possible to enter the desired receive frequency in this field. The N and A counter values are calculated
from this entry when the calculate button is pressed. Default receive frequency is 384MHz.
5.4.9
A
This is the A counter of the pulse swallow feedback divider of the PLL. The total feedback divider value is
calculated with NTOT = 32·N+A. Default value is 20.
5.4.10
N
This is the N counter of the pulse swallow feedback divider of the PLL. The total feedback divider value is
calculated with NTOT = 32·N+A. Default value is 120.
5.4.11
NTOT
This is the total feedback divider value which is calculated with NTOT=32·N+A. Default value is 3860. This
field can not be changed.
5.4.12
Calculate Button
The Calculate button triggers the calculation of new N and A counter values from the entered fRF with
respect to all other settings.
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5.4.13
LO1
The frame Injection Side defines the injection side of the LO signals into the mixers. At high side injection
the LO signal has a higher frequency than the other input signal of the mixer and vice versa. The LO1 value
is only used for calculation reasons since it has no effect on the register settings. On the other hand it has
much impact on the required LO1 frequency. Default value is high. The effect of the LO1 setting can be
observed in the Tuning Info frame (see figure in section 4.4).
5.4.14
LO2
Since mixer 2 is an image rejection mixer, we can select the right mixing product by selecting the right injection side for LO2. Default value is high. The effect of the LO2 setting can be observed in the Tuning Info
frame (see figure in section 4.4).
5.4.15
LO2DIV
These radio buttons specify the divider ratio by that the LO2 frequency is lower than the LO1 frequency. LO1
is injected into mixer 1 and LO2 is injected into mixer 2.
5.5
Register Set - Tab
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The Register Set tab gives an overview of all actual control word registers of the IC (see Data Sheet
section 4). Registers R0 to R7 with all their bits are displayed from top to bottom. The most significant bits
are on the left hand side. Red fields mean the bit is high, blue fields mean the bit is low. For ease of use the
corresponding word value in hexadecimal notation is shown on the right hand side of each control word.
Single bits can be manipulated in this tab. If the mouse pointer is moved over a field, then the bit name will
be displayed in the status field at the bottom of the dialog window and directly at the location of the mouse
pointer. A single click on a bit field toggles the state of this bit between low and high.
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Your Notes
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For the latest version of this document, go to our website at:
www.melexis.com
Or for additional information contact Melexis Direct:
Europe and Japan:
Phone: +32 1367 0495
E-mail: [email protected]
All other locations:
Phone: +1 603 223 2362
E-mail: [email protected]
ISO/TS16949 and ISO14001 Certified
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