4707 dey road liverpool, n.y. 13088 (315) 701-6751 features: series hermetic surface mount package extremely low dropout voltage: 425mv @ 7.5 amps available in 1.5v, 1.7v, 1.8v, 1.9v, 2.0v, 2.5v, 3.3v, 3.4v, 5.0v and 12.0v on board thermal shut down low ground current: 130ma typical at full load 1% maximum guaranteed accuracy output current to 7.5 amps alternate output voltages available available to dscc smd #5962-03232 description: the msk 5275 series voltage regulators are available in +1.5v, +1.7v, +1.8v, +1.9v, +2.0v, +2.5v, +3.3v, +3.4v, +5.0v and +12.0v output configurations. all boast ultra low dropout specifications due to the utilization of a super pnp output pass transistor with monolithic technology. dropout voltages of 425mv at 7.5 amps are typical in this configuration, which drives efficiency up and power dissipation down. accuracy is guaranteed with a 1% maximum output voltage tolerance. the msk 5275 series is packaged in a space efficient 3 pin power surface mount ceramic package. equivalent schematic 5275 typical applications pin-out information high efficiency, high current linear regulators constant voltage/current regulators system power supplies switching power supply post regulators battery powered equipment v in v out ground 1 2 3 1 mil-prf-38534 certified facility very high current, low dropout surface mount voltage regulators lid=isolated 8548-42 rev. j 4/12
storage temperature range . . -65c to +150c lead temperature . . . . . . . . . . . . . . . . . 300c (10 seconds soldering) operating temperature msk 5275 series . . . . . . . . . -40c to +85c msk 5275h series . . . . . . . -55to +125c input voltage (100ms 1%d.c.) input voltage enable voltage output current -20v to +60v 26v -0.3v to 26v 7.5a v inp v in v en i out t st t ld t j absolute maximum ratings 2 output current limit 2 output noise 2 thermal resistance 2 thermal shutdown 2 v out = -1%; i out = 250 ma v out = -1%; i out = 7.0a v in = v out +1v 10 ma i out 7.0a (v out +1v) v in 26v i out = 10 ma v out = 0v; v in = v out +1v v in = v out +1v; i out = 4a v in = v out +1v; i out = 7.0a c l = 33 f; 10 h z f 100 kh z junction to case t j ground current 2 1 2, 3 1 1 1 2, 3 1 2, 3 - - - - - - parameter electrical specifications - - - - - - - - - - - - - - 0.5 1.0 80 425 0.2 0.3 0.05 0.5 9.5 45 130 260 1.0 130 1.0 2.0 200 600 1.0 2.0 0.5 1.0 15 85 - - 1.2 - % % mv mv % % % % a ma ma v c/w c - - - - - - - - - - - - - - 0.5 - 80 425 0.2 0.3 0.05 0.5 9.5 45 130 260 1.0 130 1.0 - 225 625 1.2 - 0.6 - 15 90 - - 1.5 - group a subgroup msk 5275h series min. typ. max. msk 5275 series min. typ. max. units test conditions 1 3 output voltage tolerance dropout voltage 2 load regulation line regulation i out = 10ma; v in = v out +1v 1 2 3 4 5 6 7 8 9 10 notes: output decoupled to ground using 33 f minimum capacitor unless otherwise specified. this parameter is guaranteed by design but need not be tested. typical parameters are representative of actual device performance but are for reference only. all output parameters are tested using a low duty cycle pulse to maintain tj = tc. industrial grade devices shall be tested to subgroup 1 unless otherwise specified. military grade devices ('h' suffix) shall be 100% tested to subgroups 1,2,3. subgroup 1 subgroup 2 subgroup 3 please consult the factory if alternate output voltages are required. due to current limit, maximum output current may not be available at all values of v in -v out and temperatures. see typical perfomance curves for clarification. the output current limit function provides protection from transient overloads but it may exceed the maximum continuous rating. continuous operation in current limit may damage the device. continuous operation at or above absolute maximum ratings may adversely effect the device performance and/or life cycle. t c = +25c t j = +125c t a = -55c 8 10 9 8548-42 rev. j 4/12
] application notes regulator protection: the msk 5275 series is fully protected against reversed input polarity, overcurrent faults, overtemperature con- ditions (pd) and transient voltage spikes of up to 60v. if the regulator is used in dual supply systems where the load is returned to a negative supply, the output voltage must be diode clamped to ground. load connections: in voltage regulator applications where very large load currents are present, the load connection is very impor- tant. the path connecting the output of the regulator to the load must be extremely low impedance to avoid af- fecting the load regulation specifications. any imped- ance in this path will form a voltage divider with the load. minimizing power dissipation: many applications can not take full advantage of the extremely low dropout specifications of the regulator due to large input to output voltage differences. the simple circuit below illustrates a method to reduce the input voltage at the regulator to just over the dropout specifi- cation to keep the internal power dissipation minimized: for a given continuous maximum load of 1 amp, r1 can be selected to drop the voltage seen at the regulator to 4v. this allows for the output tolerance and dropout specifications. input voltage variations (5v) also should be included in the calculations. the resistor should be sized according to the power levels required for the ap- plication. output capacitor: the output voltage ripple of the msk 5275 series volt- age regulators can be minimized by placing a filter ca- pacitor from the output to ground. the optimum value for this capacitor may vary from one application to the next, but a minimum of 33 f is recommended for opti- mum performance. transient load response can also be improved by placing a capacitor directly across the load. the capacitor should not be an ultra-low esr type. tan- talum capacitors are best for fast load transients but aluminum electrolytics will work fine in most applica- tions. 3 1.7w package connections: the msk 5275 series are highly thermally conductive devices and the thermal path from the package heat sink to the internal junctions is very short. standard surface mount soldering techniques should be used when mount- ing the device. some applications may require additional heat sinking of the device. heat sink selection: to select a heat sink for the msk 5275, the following formula for convective heat flow may be used. governing equation: tj = pd x (r jc + r cs + r sa) + ta where: tj = junction temperature pd = total power dissipation r jc = junction to case thermal resistance r cs = case to heat sink thermal resistance r sa = heat sink to ambient thermal resistance ta = ambient temperature [ first, the power dissipation must be calculated as fol- lows: power dissipation = (vin - vout) x iout next, the user must select a maximum junction tempera- ture. the absolute maximum allowable junction tem- perature is 125c. the equation may now be rearranged to solve for the required heat sink to ambient thermal resistance (r sa). example: an msk 5275-3.3 is configured for vin=+5v and vout=+3.3v. iout is a continuous 1a dc level. the ambient temperature is +25c. the maximum desired junction temperature is 125c. r jc = 1.0c/w and r cs = 0.5c/w typically. power dissipation = (5v - 3.3v) x (1a) = 1.7 watts solve for r sa: r sa = 125c - 25c - 1.0c/w - 0.5c/w in this example, a heat sink with a thermal resistance of no more than 57c/w must be used to maintain a junc- tion temperature of no more than 125c. = 57.32c/w 8548-42 rev. j 4/12
typical performance curves 4 8548-42 rev. j 4/12
msk5275-3.3 h 5 the information contained herein is believed to be accurate at the time of printing. msk reserves the right to make changes to its products or specifications without notice, however, and assumes no liability for the use of its products. please visit our website for the most recent revision of this datasheet. mechanical specifications m.s. kennedy corp. 4707 dey road, liverpool, new york 13088 phone (315) 701-6751 fax (315) 701-6752 www.mskennedy.com ordering information screening blank= industrial; h= mil-prf-38534, class h output voltage 1.5=+1.5v; 1.7=+1.7v; 1.8=+1.8v; 1.9=+1.9v; 2.0=+2.0v; 2.5=+2.5v; 3.3=+3.3v; 3.4=+3.4v; 5.0=+5.0v; 12=+12.0v general part number the above example is a +3.3v, military regulator. note: all dimensions are 0.010 inches unless otherwise labeled. weight= 2.2 grams typical note: see dscc smd 5962-03232 for dscc part number options. 8548-42 rev. j 4/12
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