22 COREY STREET, MELROSE, MASSACHUSETTS 02176
PHONE (781) 665-1071
FAX (781) 665-7379
WEBSITE: http://www.cdi-diodes.com
E-mail: mail@cdi-diodes.com
CURRENT REGULATOR DIODES
CONSTANT CURRENT OVER WIDE VOLTAGE RANGE
HIGH SOURCE IMPEDANCE
METALLURGICALLY BONDED
DOUBLE PLUG CONSTRUCTION
DCR250
thru
DCR257
FIGURE 1
DESIGN DATA
CASE: Hermetically sealed glass case.
DO-7 outline.
LEAD MATERIAL: Copper clad steel.
LEAD FINISH: Tin / Lead
THERMAL RESISTANCE: (ROJEC):
250 C/W maximum at L = .375 inch
THERMAL IMPEDANCE: (ZOJX): 25
C/W maximum
POLARITY: Diode to be operated with
the banded (cathode) end negative.
MOUNTING POSITION: Any
ELECTRICAL CHARACTERISTICS @ 25C, unless otherwise specified
MINIMUM
MINIMUM
DYNAMIC
KNEE
MAXIMUM
TYPE
REGULATOR CURRENT
IMPEDANCE
IMPEDANCE
LIMITING
PEAK
NUMBER l p (mA) @ VS = 25V
@VS = 25V
@VK = 6.0 V
VOLTAGE
OPERATING
(Note 1)
ZS (K
)
ZK(K
)
@ lL = 0.8 l p (min)
VOLTAGE
NOM
MIN
MAX
(Note 2)
(Note 3)
VL (VOLTS)
VOLTS
DCR250
5.10
4.59
5.61
100
4.0
3.67
80
DCR251
5.60
5.04
6.16
90
4.0
4.03
80
DCR252
6.20
5.58
6.82
80
3.0
4.46
70
DCR253
6.80
6.12
7.48
70
2.0
4.90
70
DCR254
7.50
6.75
8.25
50
1.5
5.40
60
DCR255
8.20
7.38
9.02
30
1.5
5.90
60
DCR256
9.10
8.19
10.01
20
1.0
6.55
50
DCR257
10.00
9.00
11.10
10
1.0
7.20
50
NOTE 1
Pulse measurement @ 1% duty cycle, 10 milliseconds maximum.
NOTE 2
ZS is derived by superimposing A 90Hz RMS signal equal to 10% of VS on VS
NOTE 3
ZK is derived by superimposing A 90Hz RMS signal equal to 10% of VK on VK
MAXIMUM RATINGS
Operating Temperature: -65C to +175C
Storage Temperature: -65C to +175C
DC Power Dissipation: 500 mW @ +50C @ TL = 3/8"
Power Derating: 4 mW / C above +50C
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