Medium-Current Silicon Rectifiers

www.DataSheet4U.com TRA2525 MR3025 Medium-Current Silicon Rectifiers 250 Volts, 25 Amperes Compact, highly efficient silicon rectifiers for medium–current applications requiring: • High Current Surge — 400 Amperes @ TJ = 175°C • Peak Performance @ Elevated Temperature — 25 Amperes • Low Cost • Compact, Molded Package for Optimum Efficiency in a Small Case Configuration Mechanical Characteristics http://onsemi.com MICRODE BUTTON CASE 193 • Finish: All External Surfaces are Corrosion Resistant, and Contact • • • • Areas are Readily Solderable Polarity: Indicated by Cathode Band Weight: 1.8 Grams (Approximately) Maximum Temperature for Soldering Purposes: 260°C Marking: 2525 or MR3025 MARKING DIAGRAM 2525 LYYWW MAXIMUM RATINGS Rating DC Blocking Voltage Non–Repetitive Peak Reverse Voltage (Halfwave, Single Phase, 60 Hz) Average Forward Current (Single Phase, Resistive Load, TC = 150°C) Non–Repetitive Peak Surge Current (Halfwave, Single Phase, 60 Hz) Operating Junction Temperature Range Storage Temperature Range Symbol VR VRSM IO Value 250 310 25 Unit Volts Volts Amps 2525 L YY WW = Device Code = Location Code = Year = Work Week MARKING DIAGRAM MR3025 YYWWL IFSM TJ Tstg 400 –65 to +175 –65 to +175 Amps °C °C MR3025 = Device Code L = Location Code YY = Year WW = Work Week ORDERING INFORMATION Device TRA2525 MR3025 Package Microde Button Microde Button Shipping 5000 Units/Box 5000 Units/Box © Semiconductor Components Industries, LLC, 2000 1 October, 2000 – Rev. 1 Publication Order Number: TRA2525/D www.DataSheet4U.com THERMAL CHARACTERISTICS TRA2525 MR3025 Characteristic Thermal Resistance, Junction to Case Symbol RθJC Value 1.0 Unit °C/W ELECTRICAL CHARACTERISTICS Characteristic Instantaneous Forward Voltage (Note 1.) (IF = 100 Amps, TC = 25°C) Reverse Current(1) (VR = 250 V, TC = 25°C) (VR = 250 V, TC = 100°C) Forward Voltage Temperature Coefficient @ IF = 10 mA 1. Pulse Test: Pulse Width < 300 µs, Duty Cycle < 2%. *Typical Symbol VF IR — — VFTC *2* 10 250 *2* mV/°C Min — Max 1.18 Unit Volts µA http://onsemi.com 2 www.DataSheet4U.com TRA2525 MR3025 IFSM, PEAK HALF WAVE CURRENT (A) 1400 1350 1300 1250 V F, INSTANTANEOUS FORWARD VOLTAGE (mV) 1200 1150 1100 1050 1000 950 Maximum PW = 300 ms TJ = 25°C 1000 TJ = 25°C VRRM may be applied between each cycle of surge. The TJ noted is TJ prior to surge F = 60 Hz 1 Cycle TJ = 175°C 100 1 10 NUMBER OF CYCLES 100 Figure 2. Non–Repetitive Surge Current 0 900 850 800 750 700 650 600 1 10 100 200 IF, INSTANTANEOUS FORWARD CURRENT (A) –2.0 0.1 1 10 100 200 IF, INSTANTANEOUS FORWARD CURRENT (A) COEFFICIENT (mV/ ° C) Typical –0.5 Typical Range –1.0 –1.5 Figure 1. Forward Voltage 60 50 DC 40 30 20 10 0 120 130 140 150 160 170 180 TC, CASE TEMPERATURE (°C) IFM/IFAV = p PF(AV), AVERAGE POWER DISSIPATION (W) IF(AV), AVERAGE FORWARD CURRENT (A) 50 Figure 3. VF Temperature Coefficient 40 IFM/IFAV = p DC 30 20 10 0 0 10 20 30 40 50 IF, AVERAGE FORWARD CURRENT (A) Figure 4. Current Derating Figure 5. Forward Power Dissipation http://onsemi.com 3 www.DataSheet4U.com r(t), TRANSIENT THERMAL RESISTANCE TRA2525 MR3025 100 RqJC(t) = RqJC • r(t) Note 1 10–1 10–2 0.1 1 t, TIME (ms) 10 100 300 Figure 6. Thermal Response NOTE 1 Ppk tp t1 C, CAPACITANCE (pF) To determine maximum junction temperature of the diode in a given situation, the following procedure is recommended. The temperature of the case should be measured using a thermocouple placed on the case at the temperature reference point (see the outline drawing on page 1). The thermal mass connected to the case is normally large enough so that it will not significantly respond to heat surges generated in the diode as a result of pulse operation once steady state conditions are achieved. Using the measured value of TC, the junction temperature may be determined by: TJ = TC + DTJC Where DTJC is the increase in junction temperature above the case temperature, it may be determined by: DTJC = Ppk @ RqJC [D + (1 – D) @ r(t1 + tp) + r(tp) – r(t1)] where: r(t) = normalized value of transient thermal resistance at time, t, from Figure 6, i.e.: r(t1 + tp) = normalized value of transient thermal resistance at time t1 + tp. Ppk DUTY CYCLE, D = tp/t1 PEAK POWER, Ppk is peak of an equivalent square power pulse 1000 TJ = 25°C 100 10 0.1 1 10 100 VR, REVERSE VOLTAGE (V) Figure 7. Typical Capacitance TFR , FORWARD RECOVERY TIME (ms) VF TJ = 25°C TRR , REVERSE RECOVERY TIME (ms) 1 100 IF 0 IR IF = 1 A 10 IF = 10 A TRR TJ = 25°C 0.25 IR TFR VFR VFR = 1.0 V VFR = 2.0 V 0.1 1 IF, FORWARD CURRENT (A) 10 1 0.1 1 10 IR/IF, RATIO OF REVERSE TO FORWARD CURRENT Figure 8. Forward Recovery Time http://onsemi.com 4 Figure 9. Reverse Recovery Time www.DataSheet4U.com TRA2525 MR3025 ∂, EFFICIENCY FACTOR (%) 50 sine wave input square wave input TJ = 25°C 10 5 1 10 f, FREQUENCY (kHz) 100 Figure 10. Rectification Waveform Efficiency RECTIFICATION EFFICIENCY NOTE RS RL VO Figure 11. Single Phase Half–Wave Rectifier Circuit The rectification efficiency factor ∂ shown in Figure 10 was calculated using the formula: V2o(dc) RL RL (1) V 2o (dc) .100% 2o (ac) ) V 2o (dc) V For a square wave input of amplitude Vm, the efficiency factor becomes: V 2m 2R L . (square) + V 2m 100% + 50% RL + P (dc) P (rms) + V2o(rms) .100% + (3) For a sine wave input Vm sin(wt) to the diode, assume lossless, the maximum theoretical efficiency factor becomes: V2m p 2R L 4. . (sine) + V2m 100% + π2 100% + 40.6% 4R L (2) (a full wave circuit has twice these efficiencies) As the frequency of the input signal is increased, the reverse recovery time of the diode (Figure 9) becomes significant, resulting in an increase ac voltage component across RL which is opposite in polarity to the forward current, thereby reducing the value of the efficiency factor ∂, as shown on Figure 10. It should be emphasized that Figure 10 shows waveform efficiency only; it does not provide a measure of diode losses. Data was obtained by measuring the ac component of VO with a true rms ac voltmeter and the dc component with a dc voltmeter. The data was used in Equation 1 to obtain points for Figure 10. http://onsemi.com 5 www.DataSheet4U.com Assembly and Soldering Information TRA2525 MR3025 MECHANICAL STRESS There are two basic areas of consideration for successful implementation of button rectifiers: 1. Mounting and Handling 2. Soldering Each should be carefully examined before attempting a finished assembly or mounting operation. Mounting and Handling COMPRESSION TORSION The button rectifier lends itself to a multitude of assembly arrangements, but one key consideration must always be included: One Side of the Connections to the Button Must be Flexible! This stress relief to the button should also be chosen for maximum contact area to afford the best heat transfer — but not at the expense of flexibility. For an annealed copper terminal a thickness of 0.015″ is suggested. Strain Relief Terminal for Button Rectifier Copper Terminal Button Base (Heat Sink Material) TENSION SHEAR Exceeding these recommended maximums can result in electrical degradation of the device. Soldering The base heat sink may be of various materials whose shape and size are a function of the individual application and the heat transfer requirements. Common Materials Advantages and Disadvantages Steel Copper Aluminum Low Cost: relatively low heat conductivity High Cost: high heat conductivity Medium Cost: medium heat conductivity. Relatively expensive to plate and not all platers can process aluminum. Handling of the button during assembly must be relatively gentle to minimize sharp impact shocks and avoid nicking of the plastic. Improperly designed automatic handling equipment is the worst source of unnecessary shocks. Techniques for vacuum handling and spring loading should be investigated. The mechanical stress limits for the button diode are as follows: Compression Tension Torsion Shear 32 lbs. 32 lbs. 6–inch lbs. 55 lbs. 142.3 Newton 142.3 Newton 0.68 Newtons–meters 244.7 Newton The button rectifier is basically a semiconductor chip bonded between two nickel–plated copper heat sinks with an encapsulating material of epoxy compound. The exposed metal areas are also tin plated to enhance solderability. In the soldering process it is important that the temperature not exceed 260°C if device damage is to be avoided. Various solder alloys can be used for this operation but two types are recommended for best results: 1. 95% Sn, 5% Sb; melting point 237°C 2. 96.5% tin, 3.5% silver; melting point 221°C 3. 63% tin, 37% lead; melting point 183°C Solder is available as preforms or paste. The paste contains both the metal and flux and can be dispensed rapidly. The solder preform requires the application of a flux to assure good wetting of the solder. The type of flux used depends upon the degree of cleaning to be accomplished and is a function of the metal involved. These fluxes range from a mild rosin to a strong acid; e.g., Nickel plating oxides are best removed by an acid base flux while an activated rosin flux may be sufficient for tin plated parts. Since the button is relatively lightweight, there is a tendency for it to float when the solder becomes liquid. To prevent bad joints and misalignment, it is suggested that a weighting or spring loaded fixture be employed. It is also important that severe thermal shock (either heating or cooling) be avoided as it may lead to damage of the die or encapsulant of the part. http://onsemi.com 6 www.DataSheet4U.com TRA2525 MR3025 control but requires sophisticated temperature monitoring systems such as infrared. 3. Ovens are good for batch soldering and are production limited. There are handling problems because of slow cooling. Response time is load dependent, being a function of the watt rating of the oven and the mas