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GENERAL
Parameter
Description/Value
300 to 650
420
Bialkali
20
Borosilicate glass
Linear-focused
10
12-pin base JEDEC No. B12-43
E678-12A (supplied)
Unit
nm
nm
—
mm dia.
—
—
—
—
—
Spectral Response
Wavelength of Maximum Response
Photocathode
Window Material
Dynode
Base
Suitable Socket
Material
Minimum Effective Area
Structure
Number of Stages
PHOTOMULTIPLIER TUBE
R4998
MAXIMUM RATINGS (Absolute Maximum Values)
Parameter
Between Anode and Cathode
Between Anode and Last Dynode
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.
1999 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.
Fast Time Response, 25 mm (1 Inch) Diameter,
10-stage, Bialkali Photocathode, Head-On Type
CHARACTERISTICS (at 25
°
C)
Parameter
Luminous (2856K)
Radiant at 420nm
Blue (CS-5-58 filter)
Luminous (2856K)
Radiant at 420nm
Min.
60
—
—
100
—
—
—
—
—
Unit
μ
A/lm
mA/W
μ
A/lm-b
A/lm
A/W
—
nA
ns
ns
Value
2500
250
0.1
-30 to +50
Unit
Vdc
Vdc
mA
°
C
Supply Voltage
Average Anode Current
Ambient Temperature
Cathode Sensitivity
Anode Sensitivity
Gain
Anode Dark Current (after 30min. storage in darkness)
Time Response
Anode Pulse Rise Time
Electron Transit Time
70
72
9.0
400
4.1
×
10
5
5.7
×
10
6
100
0.7
10
—
—
—
—
—
—
800
—
—
Typ.
Max.
Supply Voltage: 2250Vdc, K: Cathode, Dy: Dynode, P: Anode
Assembled type (H6533) is recommended.
VOLTAGE DISTRIBUTION RATIO AND SUPPLY VOLTAGE
Electrodes
Ratio
1.3
4.8
1.2
1.8
K
Dy1
G
Dy2
Dy3
Dy4
Dy5
1
Dy6
1
Dy7
1
1
Dy8
Dy9
Dy10
P
1
1.5
3
2.5
NOTE:
Anode characteristics are measured with the voltage distribution ratio shown below.