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