AN7100 - Synergy Microwave Corporation

201 Mclean Blvd, Paterson, NJ 07504
AN7100 Rev. G 10/15/2013
Intelligent Interactive Synthesizer
Pinout and Functions (273LF, 197LF, 280LF packages)
This document describes the operating features and pin-out of the new generation of Synergy
Microwave’s “Intelligent Interactive Synthesizers” (I2S®). It is a generic document for the FSW
and LFSW series of (I2S®) synthesizers in packages 273LF, 197LF and 280LF. These
synthesizers are truly intelligent incorporating an internal controller that allows for optimal
factory set performance and minimal software development by the user. Programming is
easily done through four simple options that the user can adopt for fast in-circuit
implementation.
What is the need for synthesizers having an integrated controller?
There are several good reasons to do so!
• The operational settings of the PLL chip have to be calculated for each frequency
setting to be within the operational specifications. For example in wideband VCO’s, the
computation of the divider values has to guarantee that no chip internal frequency limits
are exceeded.
• The settings of the charge pump current and other parameters, which finally define the
phase noise and switching speed can be optimized easily with these intelligent
features.
• Improves the speed of the system processor and makes the software easier to re-use.
• Operation can be made independent of the PLL IC used. The use of a controller allows
change of the I2S® IC without any impact on the system software.
• Integrated error detection and signaling is possible without customer programming.
• Reduces design time for the user. A real plug and play solution!
Other benefits of the I2S® are:
• Intensive internal filtering of the supply voltages.
• Monitoring of internal voltages.
• Optimized layout to reduce impact of external ground loops.
• Standard programming interface for ALL models.
• No hardware programming for a specific PLL IC required.
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201 Mclean Blvd, Paterson, NJ 07504
AN7100 Rev. G 10/15/2013
Software Interface Pins
This section describes the software interface pins that are used to address the synthesizers.
Some of the pins are not connected and can be used at a later time for software
implementation of additional features. All I/O’s are 5V CMOS, inputs with pull-up resistors.
Their input characteristic has also been set to accommodate 3V CMOS input signals at
slightly reduced noise immunity.
•
ErrorFlag, special type output
This pin turns low after the Synthesizer has locked. (This is delayed to the Lock Detect
output due to processing time!) If any internal error is detected this pin will go high.
Internal errors are: Out of Lock, Vcc(Tune) Out of Range, Internal Voltage Regulator
Out of Range, Invalid Frequency or Reference Command.
To use this feature the pin has to be tied to ground via a pull-down resistor.
Recommended value is 120kΩ to 220kΩ. The Synthesizer will pull this output to +5V
via a 20kΩ resistor in case of an error. For communication this pin acts as the return
channel. Multiple I2S® error flags can be tied together.
•
Latch Enable
LE for SPI port. (SS)
Data In
Data for SPI port. (MOSI)
Clock In
Clock for SPI port. (SCK)
•
•
Hardware Interface Pins
•
•
•
•
•
2
Fref
Reference frequency input.
Vcc(Digital)
+5V DC supply for the digital section of the Synthesizer. A 47uF tantalum bypass
capacitor is highly recommended if the supply isn’t clean to achieve the specified phase
noise performance!
Vcc(VCO)
Supply voltage for the VCO according to the datasheet. This has to be a clean, low
noise supply. Decoupling close to the Synthesizer package is recommended.
Vcc(Tune)
Supply voltage for the VCO tuning according to the datasheet or from the internal
voltage converter. This has to be a clean, low noise supply. Decoupling close to the
Synthesizer package is recommended.
Vout(Converter) (For 197LF and 280LF packages only!)
Output of the internal voltage converter. Connect Vcc(Tune) and Vout(Converter)
201 Mclean Blvd, Paterson, NJ 07504
AN7100 Rev. G 10/15/2013
externally. No external loads allowed! A bypass capacitor of 10uF to 100uF/30V is
recommended.
•
•
•
•
•
•
Vcc (Converter) (For 197LF and 280LF package only!)
+5V supply voltage for the internal voltage converter.
Vtune - Actual tuning voltage of the VCO. Please consult factory before using this
voltage for tracking filters or other uses! Normally leave NC surrounded by ground.
Vcc(Analog)
+5V analog supply for 280LF package only! This has to be a clean, low noise supply.
Decoupling close to the Synthesizer package is recommended.
LD
Lock Detect, a 3.3V CMOS output, which turns high after the Synthesizer locks.
RFout
50Ω output of the Synthesizer.
No Connection – leave these pins open (DO NOT CONNECT TO GROUND)
Note: External noise from the power supplies must be limited to no more than
30uV/Sqrt_Hz to achieve the specified phase noise performance.
Programming
The user can address the I2S® synthesizers in one of four different options to program the
output frequency:
1.
Setting frequency allocation as a channel. In this mode, an ASCII character
code for the letter “C” in hexadecimal (43) indicates to the controller that mode
frequency as a channel is selected. The information for the channel number
follows in hexadecimal format having 32 bits with LSB sent first (total 40 bits
sent). Based on the channel selected, the controller then calculates the
frequency of the channel FCN by the following equation:
FCN = FC0 + (N*CS), where:
FCN - Frequency of the Nth channel
FC0 - Specified starting frequency of the synthesizer
Cs - Channel spacing
N - Nth channel for synthesizer to tune
For example, channel 50 for the FSW150320-50 would be sent as follows:
Data (Hex)
43 32 00 00 00
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201 Mclean Blvd, Paterson, NJ 07504
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Similarly, the synthesizer can immediately be loaded for standby channel mode
by sending ASCII character code for letter “c” in hexadecimal (63) and the data
for the next wanted channel number. The programming format for this option is
coded as “Little Endian” (MSB of the LSByte is sent first).
2.
Setting frequency by known N (division ratio). In this mode, an ASCII
character code for the letter “D” in hexadecimal (44) indicates to the controller
that mode frequency by known N is selected. N is calculated by dividing the
output frequency by the channel spacing (step size). The information for the N
division ratio follows in hexadecimal format having 32 bits with LSB sent first
(total 40 bits sent).
For example, an N ratio of 2700 would be loaded as:
Data (Hex)
44 8C 0A 00 00
Similarly, the synthesizer can immediately be loaded for standby mode by
sending ASCII character code for letter “d” in hexadecimal (64) and the data for
the next wanted known N. The programming format for this option is coded as
“Little Endian” (MSB of the LSByte is sent first).
3.
Setting frequency directly (kHz). In this mode, an ASCII character code for
the letter “K” in hexadecimal (4B) indicates to the controller that mode frequency
directly (kHz) is selected. The information is loaded in hexadecimal format (1
byte for the “K” command and 8 bytes for the frequency command (72 bits total).
No real values allowed, the instruction must be in integer format (KHz).
For example, the frequency of 4,000,000 KHz (4 GHz) would be sent as:
Data ASCII(Hex)
Hex
4B 30 30 33 44 30 39 30 30 or K003D0900
Similarly, the synthesizer can immediately be loaded for standby mode by
sending ASCII character code for letter “k” in hexadecimal (6B) and the next
wanted frequency (KHz).
4.
Setting frequency directly (MHz). In this mode, an ASCII character code for
the letter “M” in hexadecimal (4D) indicates to the controller that mode frequency
directly (MHz) is selected. The information is loaded in hexadecimal format (1
byte for the “M” command and 8 bytes for the frequency command (72 bits total).
No real values allowed, the instruction must be in integer format (MHz).
For example, the frequency of 4,000 MHz (4 GHz) would be sent as:
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201 Mclean Blvd, Paterson, NJ 07504
AN7100 Rev. G 10/15/2013
Data ASCII(Hex)
4D 30 30 30 30 30 46 41 30
or
Hex
M00000FA0
Similarly, the synthesizer can immediately be loaded for standby mode by
sending ASCII character code for letter “k” in hexadecimal (6D) and the next
wanted frequency (MHz).
Reference Frequency – The factory set reference frequency is usually 10 MHz, in
some models can be field re-programmed by the user for any reference frequency,
typically in the range of 10 to 150 MHz, as long as the reference frequency is an integer
multiple of the step size. Some models are factory set and cannot be field reprogrammed, see specification sheet for specifics on field programmability. For
synthesizer models that are not field re-programmable, contact factory for your specific
reference frequency requirement.
For those models which the reference frequency can be field reprogrammable, the
factory start-up reference frequency can be changed in two ways:
1. A volatile “R” command change, where the reference register settings are
loaded every time with each command to over ride the factory setting. There
is no limit to the number of register loads when using the “R” command
setting.
2. A non-volatile command change where the factory setting is permanently
changed in the EPROM by the user. In this case, there is a maximum limit to
the number of times that the EPROM can be written (up to 100 times). This
should be more than enough times to write to EPROM once the instruction is
written by the user for the desired reference frequency there is usually no
need to change again.
For the volatile change of the reference (setting sent with each frequency command),
an ASCII character code for the letter “R” in hexadecimal (52) indicates to the controller
that reference frequency is being temporarily changed. The information for the division
ratio follows in hexadecimal format having 32 bits with LSB sent first - 1 byte for the “R”
command and 4 bytes for the division ratio (40 bits total). The information is loaded in
hexadecimal format.
For example, with a reference frequency of 10 MHz and a step size of 500 KHz,
(division ratio of 20) the data would be sent as:
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201 Mclean Blvd, Paterson, NJ 07504
AN7100 Rev. G 10/15/2013
Data (Hex)
52 14 00 00 00
The programming format for this option is coded as “Little Endian” (MSB of the LSByte
is sent first).
For the non-volatile change of the factory setting, the letter “r” in hexadecimal (72) is
sent instead, indicating to the controller that the EPROM will be written to with a new
non-volatile user setting. The information for the division ratio similarly follows in
hexadecimal format. In this case, the four bytes of the division ratio are repeated bits
with LSB sent first – 1 byte for “r” command and 4 bytes repeated (72 bits total) and
followed by a power cycle (off/on). For example, a reference frequency of 10 MHz and
step size of 500 kHz (division ratio of 20) the data would be sent as:
Data (Hex)
72 14 00 00 00 14 00 00 00
The programming format for this option is coded as “Little Endian” (MSB of the LSByte
is sent first).
Swap Active/Standby frequencies – When an ASCII character code for the letter “S”
in hexadecimal (53) is sent, it indicates to the controller that swap frequency command
requests swapping the active and the standby frequency register settings. The
information follows in hexadecimal format having 8 bits with LSB sent first - 1 byte for
the “S” command.
Data (Hex)
53
Maximum SPI programming speed is recommended not to exceed 200kb/sec in present
designs.
By default all I2S® are set to a reference frequency of 10 MHz unless otherwise noted in the
datasheet. If the reference frequency in an application is different the first data string sent to
the Synthesizer has to be the R command! On turn on, the Synthesizer defaults to the lowest
specified frequency (channel 0). Standby frequency defaults to maximum frequency unless
otherwise specified in the datasheet.
Table I shows some examples of the different programming options and figure 1 shows a
typical timing diagram. The number of bits in the diagram below applies to the example for
MHz or kHz commands, but the timing applies for all test commands described in the above
text.
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201 Mclean Blvd, Paterson, NJ 07504
AN7100 Rev. G 10/15/2013
Suggested Connection Diagrams:
FSW Series
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201 Mclean Blvd, Paterson, NJ 07504
AN7100 Rev. G 10/15/2013
LFSW Series
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201 Mclean Blvd, Paterson, NJ 07504
AN7100 Rev. G 10/15/2013
LFSW35105-xx
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201 Mclean Blvd, Paterson, NJ 07504
AN7100 Rev. G 10/15/2013
Table I
Interface Commands
Command
Character
C
c
D
d
K
k
M
m
R
r
S
Command Description
1
2
3
Byte Position
4
5
6
Set Active Frequency as Channel
Unsigned Long Integer, LSByte first
0x43
B
B
B
B
Set Standby Frequency as Channel
Unsigned Long Integer, LSByte first
0x63
B
B
B
B
Set Active Division Ratio
Unsigned Long Integer, LSByte first
0x44
B
B
B
B
Set Standby Division Ratio
Unsigned Long Integer, LSByte first
0x64
B
B
B
B
Set Active Frequency in kHz
Hexadecimal characters
0x4B
H
H
H
H
Set Standby Frequency in kHz
Hexadecimal characters
0x6B
H
H
H
H
Set Active Frequency in MHz
Hexadecimal characters
0x4D
H
H
H
Set Standby Frequency in MHz
Hexadecimal characters
0x6D
H
H
Reference Frequency In Multiples Of
Channel Spacing
Changes factory set reference frequency
to new start-up setting
Swap Active / Standby Frequencies
Unsigned Long Integer, LSByte first
0x52
B
0x72
B
Parameter
Unsigned Long Integer, LSByte first
No parameter
7
8
9
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
B
B
B
B
B
B
B
B
B
B
0x53
All SPI communication uses most significant bit first
“B” – Binary value with least significant byte first.
“H” – ASCII value of a hexadecimal character (uppercase) most significant character first.
“C” – ASCII value of option parameter.
Examples:
“D” Command:
“F” Command:
“k” Command:
“K” Command:
“M” Command:
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Set Active N using Division Ratio of 2700 
Set Active N using Preset Frequency #1 
Set Standby N using Frequency of 1100000kHz 
Set Active N using Frequency of 4000000kHz 
Set Active N using Frequency of 4000MHz 
44 8C 0A 00 00 (2700 = 0x00000A8C)
46 01
6B 30 30 31 30 43 38 45 30 or “k0010C8E0”
4B 30 30 33 44 30 39 30 30 or “K003D0900”
4D 30 30 30 30 30 46 41 30 or “M00000FA0”
201 Mclean Blvd, Paterson, NJ 07504
AN7100 Rev. G 10/15/2013
TIMING DIAGRAM
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201 Mclean Blvd, Paterson, NJ 07504
AN7100 Rev. G 10/15/2013
Rev. “B” In-circuit programming section: Changed series resistor value statement for error flag,
clock, data, reset to 1k ohms from 10k ohms. Added suggested connection diagrams.
Rev. “C” Changed timing diagram.
Rev. “D” Added information to re-program the factory reference frequency setting by sending a nonvolatile “r” command.
Rev. “E” Reference in bullet 5 on page 1 referencing in-circuit firmware upgradeability and page 3
were removed. Reference Frequency paragraph on Page 5 was corrected to include reference for field
re-programmability of the reference frequency on some models. Revised connection diagrams to
remove optional for in circuit programming reference and removed reference to the reset pin to avoid
possible unintended re-programming of the factory settings in the field. Contact is now labeled in
spec sheet NC without reference. Reset is for internal use only.
Rev. “F” Changed timing diagram to indicate T1 as >5 uSec instead of 10 clock cycles.
Rev. “G” Pin 10 is now NC therefore L10, C12 and Vcc(Converter) label was removed. Also
labeled pin 16 and pin 14 since they had no labels in the schematic.
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