CIRCUIT DESIGN STD-302 User manual

OG_STD-302-419M_v10e
OPERATION GUIDE
UHF Narrow band radio transceiver
STD-302 419MHz
Operation Guide
Version 1.0 (Jan 2004)
CIRCUIT DESIGN, INC.,
7557-1 Hotaka, Hotaka-machi,
Minamiazumi, Nagano 399-8303 JAPAN
Tel: + [phone]
Fax: + [phone]
e-mail: [email protected]
http://www.circuitdesign.jp

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OPERATION GUIDE
CONTENTS
GENERAL DESCRIPTION & FEATURES ...........................3
SPECIFICATIONS STD-302 419 MHz .............................4
PIN DESCRIPTION .............................................................5
BLOCK DIAGRAM...............................................................7
DIMENSIONS......................................................................8
PLL IC CONTROL ...............................................................9
PLL IC control ....................................................................9
How to calculate the setting values for the PLL register ........10
Method of serial data input to the PLL................................. 11
TIMING CHART.................................................................12
PLL FREQUENCY SETTING REFERENCE .....................14
REGULATORY COMPLIANCE INFORMATION ................15
CAUTIONS & WARNINGS ................................................16

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OPERATION GUIDE
GENERAL DESCRIPTION & FEATURES
General Description
The UHF FM narrow band semi-duplex radio data module STD-302 is a high performance
transceiver designed for use in industrial applications requiring long range, high performance and
reliability.
All high frequency circuits are enclosed inside a robust housing to provide superior resistance
against shock and vibration. A narrow band technique enables high interference rejection and
concurrent operation with multiple modules.
STD-302, a narrowband module with 25 kHz channel steps, achieves high TX/RX switching speed,
making it an ideal RF unit for inclusion in feedback systems.
Features
 10 mW RF power, 3.0 V operation
 Programmable RF channel
 Fast TX/RX switching time (5 ms)
 High sensitivity -119 dBm
 Excellent mechanical durability, high vibration & shock resistance
Applications
 Telem e t r y
Water level monitor for rivers, dams, etc.
Monitoring systems for environmental data such as temperature, humidity, etc.
Transmission of measurement data (pressure, revolution, current, etc) to PC
Security alarm monitoring
 Telecontrol
Industrial remote control systems
Remote control systems for factory automation machines
Control of various driving motors
 Data transmission
RS232/RS485 serial data transmission

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OPERATION GUIDE
SPECIFICATIONS
STD-302 419 MHz All ratings at 25°C unless otherwise noted
Parameter Rating Conditions
General characteristics
Communication method Semi-duplex
Oscillation type PLL Controlled VCO
Operating frequency range 418.725-419.425 MHz
Channel step Programmable
Frequency stability +/- 4 ppm -10 to +55 °C
+/- 8 ppm -20 to +65 °C
Data rate 9600 bps max. Input data pulse width: Min104µs, Max 5 ms
PLL reference frequency 21.25 MHz
Operating temperature range - 10 to + 55 °C
- 20 to + 65 °C *A
Operating voltage range 3 - 5.5 V
Dimensions 30 x 50 x 9 mm
Transmitter part
RF output power 9.0 mW Antenna impedance 50 Ω
Deviation 2.5 kHz +/-0.35 kHz PN9, 9600 bps, LPF 20 kHz
Deviation frequency
characteristics +/- 3 dB 50 - 4800 Hz
Residual FM noise 0.17 kHz LPF 20 kHz
TX S/N -30 dB 1 kHz, Dev.= +/-2.4 kHz CCITT filter
Spurious emission -60 dBm < 1 GHz
-43 dBm > 1 GHz
Adjacent channel leakage
power -37 dB CH 25 kHz, BW 16 kHz, PN9, 9600 bps
Total distortion and noise 30 dB 1 kHz, Dev.+/-2.4 kHz, CCITT filter
Consumption current 40 mA
Switching time RX to TX 5 - 10 ms RX -> TX * 1
Lock time 30 - 40 ms Free Run -> TX * 2
10 - 20 ms 25 kHz channel shift * 3
Receiver part
Reception method Double superheterodyne
Sensitivity -119 dBm (AF OUT) 1 kHz, Dev.+/-2.4 kHz, CCITT filter
Bit error rate -110 dBm (Data Out) 9600 bps, PN9 (1/2556 bit error), Internal synchronous
AF output 150+/-35 mVrms fmod.+/- 2.4 kHz, fm+/-1.2 kHz (RF level -30 dBm)
140+/-35 mVrms
fmod.+/- 2.4 kHz, fm+/-2.4 kHz (RF level -30 dBm)
120+/-45 mVrms
fmod.+/- 2.4kHz, fm+/-4.8 kHz (RF level -30 dBm)
RX S/N 35 dB 1 kHz, Dev.+/-2.4 kHz, CCITT filter (RF level -30 dBm)
Distortion -30 dB
1 kHz, Dev.+/-2.4 kHz, CCITT filter (RF level -30 dBm)
Spurious emission -60 dBm
Spurious sensitivity 45 dB Two signal method, Jamming signal = FM
Intermodulation 45 dB Two signal method
Adjacent channel selectivity 45 dB Two signal method, CH 25 kHz,
Jamming signal = FM
Consumption current 26 mA
Switching time TX to RX 5 - 10 ms TX -> RX * 1
Lock Time 30 - 40 ms Free Run -> RX * 2
10 - 20 ms 25 kHz channel shift * 3
*A Under -10°C, the time required till effective data is output from DO is longer than that at normal temperature. It is
recommended to use a preamble which is twice the length of the usual preamble. Please refer to page 12.
* 1 Time required for the TX frequency or 1st local frequency to reach within +/-1.5 ppm of a stable frequency.
* 2 Time required for the TX frequency or 1st local frequency to reach within +/-1.5 ppm of a stable frequency after PLL setting
data is output.
* 3 Time required for the TX frequency or 1st local frequency to reach within +/-1.5 ppm of a stable frequency after PLL setting
data for 25kHz shift is output.

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OPERATION GUIDE
PIN DESCRIPTION
Pin name I/O Description Equivalent circuit
RF I/O
RF input terminal
Antenna impedance nominal 50 Ω
GND I
GROUND terminal
The GND pins and the feet of the shield case
shoud be connected to the wide GND
pattern.
VCC I
Power supply terminal
DC 3.0 to 5.5 V
TXSEL I
TX select terminal
GND = TXSEL active
To enable the transmitter circuits, connect
TXSEL to GND and RXSEL to OPEN or 2.8
V.
RXSEL I
RX select terminal
GND= RXSEL active
To enable the receiver circuits, connect
RXSEL to GND and TXSEL to OPEN or 2.8
V.
AF I
Analogue output terminal
There is DC offset of approx. 1 V.
Refer to the specification table for amplitude
level.
CLK I
PLL data setting input terminal
Interface voltage H = 2.8 V, L = 0 V
DATA I
PLL data setting input terminal
Interface voltage H = 2.8 V, L = 0 V
LE I
PLL data setting input terminal
Interface voltage H = 2.8 V, L = 0 V
100nH
47P
RF
GND
SAW FILTER
REG
VCC
47P
10µ
22µ47P
2.8V
2.8V
10
TXSEL
2.8V 20K
2.8V
10
RXSEL
2.8V 20K
MB15E03
CLK
2K
MB15E03
DATA
2K
MB15E03
LE
2K

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OPERATION GUIDE
LD O
PLL lock/unlock monitor terminal
Lock = H (2.8 V), Unlock = L (0 V)
RSSI O
Received Signal Strength Indicator terminal
DO O
Data output terminal
Interface voltage: H=2.8V, L=0V
DI I
Data input terminal
Interface voltage: H=Vcc, L=0V
Input data pulse width Min.104 µs Max.5 ms
2K
MB15E03
102
2.8V
LD
102
DO
2K
10K
2.8V

OPERATION GUIDE.
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BLOCK DIAGRAM <STD-302 419 MHz>

OPERATION GUIDE.
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DIMENSIONS
Reference hole position for PCB mounting (Bottom view)
419MHz

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OPERATION GUIDE
PLL IC CONTROL
 PLL IC control
OSCin
OSCout
Vp
VCC
Do
GND
Xf in
Fin
R
PSTD-302
Control pin name
ZC
PS
LE
Data
2kohm
MB15E03SL
Reference Oscillator
LPF
Voltage Controled
Oscillator
VCO
PLL
CLK
DATA
LE
LD
LD/f out
+2.8v
#:Control v oltage = +2.8v
21.25MHz
up to 1200MHz
Figure 1
CLK
2kohm
2kohm
2kohm
STD-302 is equipped with an internal PLL frequency synthesizer as shown in Figure 1. The operation of the
PLL circuit enables the VCO to oscillate at a stable frequency. Transmission frequency is set externally by the
controlling IC. STD-302 has control terminals (CLK, LE, DATA) for the PLL IC and the setting data is sent to
the internal register serially via the data line. Also STD-302 has a Lock Detect (LD) terminal that shows the
lock status of the frequency. These signal lines are connected directly to the PLL IC through a 2 kΩresistor.
The interface voltage of STD-302 is 2.8 V, so the control voltage must be the same.
STD-302 comes equipped with a Fujitsu MB15E03SL PLL IC. Please refer to the manual of the PLL IC.
The following is a supplementary description related to operation with STD-302. In this description, the same
names and terminology as in the PLL IC manual are used, so please read the manual beforehand.

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OPERATION GUIDE
 How to calculate the setting values for the PLL register
The PLL IC manual shows that the PLL frequency setting value is obtained with the following equation.
fvco = [(M x N)+A] x fosc / R -- Equation 1
fvco : Output frequency of external VCO
M: Preset divide ratio of the prescaler (64 or 128)
N: Preset divide ratio of binary 11-bit programmable counter (3 to 2,047)
A: Preset divide ratio of binary 7-bit swallow counter (0 ≤A ≤127 A<N))
fosc: Output frequency of the reference frequency oscillator
R: Preset divide ratio of binary 14-bit programmable reference counter (3 to 16,383)
With STD-302, there is an offset frequency (foffset) 21.7 MHz for the transmission RF channel frequency fch.
Therefore the expected value of the frequency generated at VCO (fexpect) is as below.
fvco = fexpect = fch – foffset ---- Equation 2
The PLL internal circuit compares the phase to the oscillation frequency fvco. This phase comparison
frequency (fcomp) must be decided. fcomp is made by dividing the frequency input to the PLL from the reference
frequency oscillator by reference counter R. STD-302 uses 21.25 MHz for the reference clock fosc. fcomp is one
of 6.25 kHz, 12.5 kHz or 25 kHz.
The above equation 1 results in the following with n = M x N + A, where “n” is the number for division.
fvco=n*fcomp ---- Equation 3 n = fvco/fcomp ---- Equation 4 note: fcomp = fosc/R
Also, this PLL IC operates with the following R, N, A and M relational expressions.
R=fosc/fcomp ---- Equation 5 N = INT (n / M) ---- Equation 6 A = n - (M x N) ---- Equation 7
INT: integer portion of a division.
As an example, the setting value of RF channel frequency fch 869.725 MHz can be calculated as below.
The constant values depend on the electronic circuits of STD-302.
Conditions: Channel center frequency: fch = 869.725 MHz
Constant: Offset frequency: foffset=21.7 MHz
Constant: Reference frequency: fosc=21.25 MHz
Set 25 kHz for Phase comparison frequency and 64 for Prescaler value M
The frequency of VCO will be
fvco = fexpect = fch - foffset = 869.725 –21.7 = 848.025MHz
Dividing value “n” is derived from Equation 4
n = fvco / fcomp = 848.025MHz/25kHz = 33921
Value “R” of the reference counter is derived from Equation 5.
R = fosc/fcomp = 21.25MHz/25kHz = 850
Value “N” of the programmable counter is derived from Equation 6.
N = INT (n/M) = INT(33921/64) = 530
Value “A“ of the swallow counter is derived from Equation 7.
A = n – (M x N) = 33921 – 64 x 530 = 1
The frequency of STD-302 is locked at a center frequency fch by inputting the PLL setting values N, A and R
obtained with the above equations as serial data. The above calculations are the same for the other
frequencies.
Excel sheets that contain automatic calculations for the above equations can be found on our web site
(www.circuitdesign.jp/eng/).
The result of the calculations is arranged as a table in the CPU ROM. The table is read by the channel
change routine each time the channel is changed, and the data is sent to the PLL.

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OPERATION GUIDE
 Method of serial data input to the PLL
After the RF channel table plan is decided, the data needs to be allocated to the ROM table and read from
there or calculated with the software.
Together with this setting data, operation bits that decide operation of the PLL must be sent to the PLL.
The operation bits for setting the PLL are as follows. These values are placed at the head of the reference
counter value and are sent to the PLL.
1. CS: Charge pump current select bit
CS = 0 +/-1.5 mA select VCO is optimized to +/-1.5 mA
2. LDS: LD/fout output setting bit
LDS = 0 LD select Hardware is set to LD output
3. FC: Phase control bit for the phase comparator
FC = 1 Hardware operates at this phase
The PLL IC, which operates as shown in the block diagram in the manual, shifts the data to the 19-bit shift
register and then transfers it to the respective latch (counter, register) by judging the CNT control bit value
input at the end.
1. CLK [Clock]: Data is shifted into the shift register on the rising edge of this clock.
2. LE [Load Enable]: Data in the 19-bit shift register is transferred to respective latches on the rising edge of
the clock. The data is transferred to a latch according to the control bit CNT value.
3. Data [Serial Data]: You can perform either reference counter setup or programmable counter setup first.
CS
Inv alid Data
LDS FC SW R14 R13 CNT=1
R1
1st data
2nd data N11 N10 N9 N8 N7 N6 CNT=0A1
1st Data 2nd Data
DATA
CLK
LE
MSB LSB
t6
t5t4
t3t2t1
t0
#: t0,t5 >= 100 ns t1,t2,t6 >= 20 ns t3,t4 >= 30 ns
#: Keep the LE terminal at a low level, w hen w rite the data to the shift resister.
STD-302
terminal name
Figure 2

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OPERATION GUIDE
TIMING CHART
Control timing in a typical application is shown in Figure 3.
Initial setting of the port connected to the radio module is performed when power is supplied by the CPU and
reset is completed. MOS-FET for supply voltage control of the radio module, RXSEL and TXSEL are set to
inactive to avoid unwanted emissions. The power supply of the radio module is then turned on. When the
radio module is turned on, the PLL internal resistor is not yet set and the peripheral VCO circuit is unstable.
Therefore data transmission and reception is possible 40 ms after the setting data is sent to the PLL at the
first change of channel, however from the second change of channel, the circuit stabilizes within 20 ms and is
able to handle the data.
Changing channels must be carried out in the receive mode. If switching is performed in transmission mode,
unwanted emission occurs.
If the module is switched to the receive mode when operating in the same channel, (a new PLL setting is not
necessary) it can receive data within 5 ms of switching*1. For data transmission, if the RF channel to be used
for transmission is set while still in receiving mode, data can be sent at 5 ms after the radio module is
switched from reception to transmission*2.
Check that the Lock Detect signal is “high” 20 ms after the channel is changed. In some cases the Lock
Detect signal becomes unstable before the lock is correctly detected, so it is necessary to note if processing
of the signal is interrupted. It is recommended to observe the actual waveform before writing the process
program.
*1 DC offset may occur due to frequency drift caused by ambient temperature change. Under conditions below
-10 °C, 10 to 20 ms delay of DO output is estimated. The customer is urged to verify operation at low
temperature and optimize the timing.
*2 Sending ‘10101…..’ preamble just after switching to transmission mode enables smoother operation of the
binarization circuit of the receiver.
For 9600 bps, a preamble of ‘11001100’ is effective.
Recommended preamble length:
-10 °C - +55°C: 15 ms
-20 °C - +65 °C (for operation exceeding the above range): 30 ms
Remark
For details about PLL control and the sample programs, see our technical document ‘STD-302 interface
method’

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OPERATION GUIDE
Receiv e mode
RXSEL
STD-302
Po w e r o n
TXSEL
CPU c ont rol,
CH change
&
Data rec.
Timing
Data transmit
#:6 10 to 20 ms later, the receiver can receive the data after changing the channel.
Data #:6
LD
CH CH
Data #:7
5 ms
10 to 20 ms
#:4 RFchannel change must be perf ormed in receiving mode.
#:7 5 ms later, the data can be received if the RF channel is not changed.
5 ms #:4
40 ms
CPU
Po w e r o n
CH Data #:5
5 ms 5 ms
Check LD signal
Check LD signal
Normal statusStatus immediately after pow er comes on.
Channel change No channel change
#:4
#:2 Initialize the port connected to the module. #:3 Supply pow er to the module after initializing CPU. #:1 Reset control CPU
#:1 #:2 #:4
#:3
#:5 40 ms later, the receiver can receive the data after changing the channel..
Figure 3: Timing diagram for STD-302
activ e period
Receiv e mode
active period
Receive mode
activ e period
Tran s m it m o de
activ e
Check LD signal
Activ e period
Tran s m it m o de
activ e
Tran s m it m o de
activ e

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PLL FREQUENCY SETTING DATA REFERENCE
419 MHz ISM band (418.725 – 419.425 MHz)
Channel Frequency
FCH
Expect
Frequency
FEXPECT
Lock
Frequency
FVCO
No.
(MHz) (MHz) (MHz)
Number of
Division n
Programmable
Counter N
Swallow
Counter A
0 418.7250 397.0250 397.0250 15881 248 9
1 418.7500 397.0500 397.0500 15882 248 10
2 418.7750 397.0750 397.0750 15883 248 11
3 418.8000 397.1000 397.1000 15884 248 12
4 418.8250 397.1250 397.1250 15885 248 13
5 418.8500 397.1500 397.1500 15886 248 14
6 418.8750 397.1750 397.1750 15887 248 15
7 418.9000 397.2000 397.2000 15888 248 16
8 418.9250 397.2250 397.2250 15889 248 17
9 418.9500 397.2500 397.2500 15890 248 18
10 418.9750 397.2750 397.2750 15891 248 19
11 419.0000 397.3000 397.3000 15892 248 20
12 419.0250 397.3250 397.3250 15893 248 21
13 419.0500 397.3500 397.3500 15894 248 22
14 419.0750 397.3750 397.3750 15895 248 23
15 419.1000 397.4000 397.4000 15896 248 24
16 419.1250 397.4250 397.4250 15897 248 25
17 419.1500 397.4500 397.4500 15898 248 26
18 419.1750 397.4750 397.4750 15899 248 27
19 419.2000 397.5000 397.5000 15900 248 28
20 419.2250 397.5250 397.5250 15901 248 29
21 419.2500 397.5500 397.5500 15902 248 30
22 419.2750 397.5750 397.5750 15903 248 31
23 419.3000 397.6000 397.6000 15904 248 32
24 419.3250 397.6250 397.6250 15905 248 33
25 419.3500 397.6500 397.6500 15906 248 34
26 419.3750 397.6750 397.6750 15907 248 35
27 419.4000 397.7000 397.7000 15908 248 36
28 419.4250 397.7250 397.7250 15909 248 37
Parameter name Value
Phase Comparing Frequency Fcomp [kHz] 25
Start Channel Frequency Fch [MHz] 418.7250
Channel Step Frequency [kHz] 25
Number of Channel 29
Prescaler M64
Parameter name Value
Reference Frequency Fosc [MHz] 21.25
Offset Frequency Foffset [MHz] 21.7
: For data input
: Result of calculation
: Fixed value
Parameter name Value
Reference Counter R850
Programmable Counter N Min. Value 248
Programmable Counter NMax. Value 248
Swallow Counter AMin. Value 9
Swallow Counter AMax. Value 37

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Regulatory compliance information
Compliance
STD-302 419 MHz was designed to be installed in radio equipment for use in China. The regulations and the
technical specifications referred to in the design phase are shown in Table 1 and 2 below.
Table 1 Regulation
Product STD-302 419 MHz
Country China
Application specified 419 MHz band for industrial remote control device
Generic regulation Preliminary regulation for low power (short range) devices (Ministry
of Information Industry May 1998)
Reference URL SRRC: http://www.srrc.gov.cn/
Table 2 Specification
Specification specified in the generic regulation
Frequency 418.950 MHz, 418.975 MHz, 419.000 MHz, 419.025 MHz,
419.050 MHz, 419.075 MHz, 419.100 MHz, 419.125 MHz,
419.150 MHz, 419.175 MHz, 419.200 MHz, 419.250 MHz,
419.275MHz
Output power <10 mW
Band width <16 kHz
Spurious emission <2.5 µW
Frequency tolerance <4 x 10-6
The relevant laws and regulations are subject to change. Circuit Design, Inc. is not responsible for the validity and
the accuracy of our understanding and translation relating to the regulation and specification above.
Compliance assessment
This product was designed to meet the specification above, however it has not been assessed for conformity with
the appropriate regulations. Uses are required to verify that their final product meets the appropriate specifications
and to perform the procedures for regulatory compliance.
Guarantee of regulatory compliance
We only guarantee that this product meets the specification in this document. We are exempt from any other
responsibilities relating to regulatory compliance.
We also recommend that the user consults the authorities in the relevant country for detailed regulatory information
such as valid regulations, test specifications, assessment procedures, marking methods etc, before starting any
project with this product.
If technical documentation is required for compliance assessments, we will provide any documents, which may be
considered necessary for assessment, under NDA. The documentation is only available in English.

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OPERATION GUIDE
Cautions
•As the radio module communicates using electronic radio waves, there are cases where transmission will be
temporarily cut off due to the surrounding environment and method of usage. The manufacturer is exempt from
all responsibility relating to resulting harm to personnel or equipment and other secondary damage.
•Do not use the equipment within the vicinity of devices that may malfunction as a result of electronic radio waves
from the radio module.
•The manufacturer is exempt from all responsibility relating to secondary damage resulting from the operation,
performance and reliability of equipment connected to the radio module.
•Communication performance will be affected by the surrounding environment, so communication tests should be
carried out before actual use.
•Ensure that the power supply for the radio module is within the specified rating. Short circuits and reverse
connections may result in overheating and damage and must be avoided at all costs.
•Ensure that the power supply has been switched off before attempting any wiring work.
•The case is connected to the GND terminal of the internal circuit, so do not make contact between the '+' side of
the power supply terminal and the case.
•When batteries are used as the power source, avoid short circuits, recharging, dismantling, and pressure.
Failure to observe this caution may result in the outbreak of fire, overheating and damage to the equipment.
Remove the batteries when the equipment is not to be used for a long period of time. Failure to observe this
caution may result in battery leaks and damage to the equipment.
•Do not use this equipment in vehicles with the windows closed, in locations where it is subject to direct sunlight,
or in locations with extremely high humidity.
•The radio module is neither waterproof nor splash proof. Ensure that it is not splashed with soot or water. Do not
use the equipment if water or other foreign matter has entered the case.
•Do not drop the radio module or otherwise subject it to strong shocks.
•Do not subject the equipment to condensation (including moving it from cold locations to locations with a
significant increase in temperature.)
•Do not use the equipment in locations where it is likely to be affected by acid, alkalis, organic agents or corrosive
gas.
•Do not bend or break the antenna. Metallic objects placed in the vicinity of the antenna will have a great effect
on communication performance. As far as possible, ensure that the equipment is placed well away from metallic
objects.
•The GND for the radio module will also affect communication performance. If possible, ensure that the case
GND and the circuit GND are connected to a large GND pattern.
Warnings
•Do not take a part or modify the equipment.
•Do not remove the product label (the label attached to the upper surface of the module.) Using a module from
which the label has been removed is prohibited.
Circuit Design, Inc. All right reserved
No part of this document may be copied or distributed in part or in whole without the prior written consent o
f
Circuit Design, Inc.
Customers are advised to consult with Circuit Design sales representatives before ordering.
Circuit Design, Inc. believes the furnished information is accurate and reliable. However, Circuit Design, Inc.
reserves the right to make changes to this product without notice.