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UV TRON
UV TRON
®
DRIVING CIRCUIT
C3704 SERIES
Compact, Lightweight, Low Current Consumption, Low Cost
Operates as High Sensitivity UV Sensor with UV TRON
Suitable for Flame Detectors and Fire Alarms
APPLICATIONS
Flame detectors for gas and oil lighters
Fire alarms
Arson watch monitor
Combustion monitors for burners
Electric spark detector
UV photoelectric counter
Hamamatsu C3704 series UV TRON driving circuits are low
current consuming, signal processing circuits for the UV TRON,
well known as a high sensitivity ultraviolet detecting tube. The
C3704 series can be operated as a UV sensor by connecting
the UV TRON and applying DC low voltage, as they have both
a high-voltage power supply and a signal processing circuit on
the same printed circuit board.
Since background discharges of the UV TRON caused by natu-
ral excitation lights (such as a cosmic ray, scattered sunlight,
etc.) can be cancelled in the signal processing circuit, the out-
put signals from the C3704 series can be used without errors.
When the high sensitivity sensor UV TRON R2868 (sold sep-
arately) is used, the flame from a cigarette lighter (flame
length: 25mm) can be detected even from a distance of more
than 5m.
Information furnished by HAMAMATSU is believed to be reliable. However, no responsibility is assumed for possible inaccuracies or omissions. Specifications are
subject to change without notice. No patent rights are granted to any of the circuits described herein. ©2006 Hamamatsu Photonics K.K.
Subject to local technical requirements and regulations, availability of products included in this promotional material may vary. Please consult with our sales office.
Figure 1: Dimensional Outline (Unit : mm)
TPT A0024EA
- + 1 2 3
9
7
5
3
K
A
3.5
4-
Top View
Side View
60
5
60
5
1.6
15
MAX.
SPECIFICATIONS
1The output pulse width can be extended up to about 100s by adding
a capacitor to the circuit board.
2Since the output impedance of this power supply is extremely high,
an ordinary voltmeter cannot be used. Use a voltmeter that has an
input impedance of more than 10 G
.
3No condensation
NOTE:
Unit
Parameter
Output Signal
UV TRON Supply Voltage
Quenting Time
Suitable UV TRON
Operating Ambient Temperature
Input Voltage
Current
Consumption
Weight
C3704
C3704-02
C3704-03
C3704
C3704-02
C3704-03
Open Collector Output
(50 V, 100 mA Max.)
10 ms with pulse output
1
350
2
Approx. 50
Low Voltage Operation UV TRON
(such as R2868)
-10 to +50
3
10 to 30
5
± 0.25
6 to 9
3
300
300
Approx. 20 V
ms °C
V
V
V
mA MAX.
µA MAX.
µA MAX.
g
Description / Value UV TRON

®
DRIVING CIRCUIT C3704 SERIES
Figure 2: Schematic Diagram
TPT C0004EA
Figure 3: Method of Connection
TPT 1007E02
APR. 2006 IP
HAMAMATSU PHOTONICS K.K., Electron Tube Division
314-5, Shimokanzo, Iwata City, Shizuoka Pref., 438-0193, Japan, Telephone: (81)539/62-5248, Fax: (81)539/62-2205
U.S.A.: Hamamatsu Corporation: 360 Foothill Road, P. O. Box 6910, Bridgewater. N.J. 08807-0910, U.S.A., Telephone: (1)908-231-0960, Fax: (1)908-231-1218 E-mail: usa@hamamatsu.com
Germany: Hamamatsu Photonics Deutschland GmbH: Arzbergerstr. 10, D-82211 Herrsching am Ammersee, Germany, Telephone: (49)8152-375-0, Fax: (49)8152-2658 E-mail: info@hamamatsu.de
France: Hamamatsu Photonics France S.A.R.L.: 19, Rue du Saule Trapu, Parc du Moulin de Massy, 91882 Massy Cedex, France, Telephone: (33)1 69 53 71 00, Fax: (33)1 69 53 71 10 E-mail: infos@hamamatsu.fr
United Kingdom: Hamamatsu Photonics UK Limited: 2 Howard Court, 10 Tewin Road Welwyn Garden City Hertfordshire AL7 1BW, United Kingdom, Telephone: 44-(0)1707-294888, Fax: 44(0)1707-325777 E-mail: info@hamamatsu.co.uk
North Europe: Hamamatsu Photonics Norden AB: Smidesvägen 12, SE-171-41 SOLNA, Sweden, Telephone: (46)8-509-031-00, Fax: (46)8-509-031-01 E-mail: info@hamamatsu.se
Italy: Hamamatsu Photonics Italia: S.R.L.: Strada della Moia, 1/E, 20020 Arese, (Milano), Italy, Telephone: (39)02-935 81 733, Fax: (39)02-935 81 741 E-mail: info@hamamatsu.it
WEB SITE www.hamamatsu.com
K
A
CATHODE
ANODE
+ GND
JUMPER LEAD FOR SETTING
BACKGROUND CANCEL LEVEL
Q (1)
Q (2)
10 ms
4
GND
GND
5 V
5 V
Q
Q
7
3
9
5
+350 V
Tr: 50 V 100 mA
+5 V
UV TRON
(SOLD SEPARATELY)
POWER SUPPLY
CONSTANT *
VOLTAGE
CIRCUIT
HIGH VOLTAGE
DC-DC
CONVERTER
* Not included in C3704-02.
OPEN COLLECTOR
OUTPUT (3)
OUTPUT SIGNAL
WAVEFORM
SIGNAL
PROCESSING
CIRCUIT
PRECAUTIONS FOR USE
Since the operation impedance is extremely high, the UV TRON should be connected as close as possible to the circuit
board within 5 cm.
Take care to avoid external noise since a C-MOS IC is used in the circuit. It is recommended that the whole PC board be
put in the shield box when it is used.
To reduce current consumption, oscillating frequency is very low (approx. 20 Hz) in this DC-DC converter. Thus, the
output impedance of the high voltage power supply is extremely high. If the surrounding humidity is high, electrical
leakage on the PC board surface may lead to a drop in the supply voltage to the UV TRON. This voltage drop may result
in lowered detection performance, so a moistureproof material (silicone compound, etc.) should be applied at the
connecting point of the UV TRON, etc., if using the unit in a humid environment.
4
5
This background cancel circuit outputs signal
pulses of 10ms width only when 3 to 9 pulses
enter the circuit with a time interval of 2
seconds or less from the UV TRON. Cancel
level can be set in 4 steps (number of pulses:
3, 5, 7, 9) by this jumper lead. Connect to 3
for general use. When using where much
natural excitation light is present, set the
cancel level at a higher step (5, 7, 9).
JUMPER LEAD FOR SETTING
BACKGROUND CANCEL LEVEL
POWER SUPPLY INPUT AND SIGNAL OUTPUT POINT
Cx: POINT FOR ADDING A CAPACITOR TO
EXTEND OUTPUT PULSE WIDTH
:
+:
1:
2:
3:
CONNECTING POINT OF UV TRON
A: Connecting Anode of UV TRON
K: Connecting Cathode of UV TRON
GND
POWER SUPPLY INPUT
SIGNAL OUTPUT Q
SIGNAL OUTPUT Q
OPEN COLLECTOR OUTPUT
4No load can be driven by an output from points 1 and 2 because these
signals are output from the only C-MOS IC directly. When a load such as a
buzzer and a relay is connected to this circuit, it should be connected to the
point open collector output. The transistor ratings of the open collector is
50 V, 100 mA. Be careful not to exceed the ratings.
5The output pulse width is set to 10 ms at shipping. If the pulse width needs
to be extended, add a capacitor to this point. (When using an electrolytic
condenser, make sure the polarity is correct.)
e.g. CX: 1
µF Pulse Width: Approx. 1 s, CX: 10 µF Pulse Width: Approx.10 s
NOTE: