FEATURES • • • • • • • • • • • LINE INTERFACE MODULE 40 TO 80 VDC INPUT -55°C to +125°C operation 40 to 80 VDC input Fixed frequency, 550 kHz typical Topology – Non-isolated buck 35 VDC input with lowered efficiency Withstands transients of up to 90 V for up to120 ms. 35 VDC output Inhibit function Power readiness function Load fault/short circuit protection Up to 94% efficiency, 90 W/in3 LIM SERIES 50 - 250 WATT MODEL THROUGHPUT POWER MODEL LIM5050™ LIM50250™ WATTS 50 250 LIM5050 Size (max.): Non flanged 1.460 x 1.130 x 0.330 (37.08 x 28.70 x 8.38 mm) Flanged 2.005 x 1.130 x 0.330 (50.93 x 28.70 x 8.38 mm) See Section B8, cases E1 and G1, for dimensions. Weight: 30 grams typical Screening: Standard, ES, or 883 See Section C2 for screening options, see Section A5 for ordering information. DESCRIPTION The LIM50™ Series of line interface modules provide a nominal output voltage of 35 VDC from input voltages of 45 to 75 VDC with efficiencies of 94% or higher. Sustained operation at voltages as high at 80 or as low as 35 are possible with reduced efficiency. The LIM5050 module delivers 50 watts of output power over the full military temperature range of –55°C to +125°C and fits in a package of 1.460 x 1.130 x 0.330 inches (37.08 x 28.70 x 8.38 mm) maximum, resulting in a power density of 91 watts/in3. SCREENING The LIM Series™ modules offer three screening options – Standard, ES, or 883. See Section C2, Screening, for descriptions. CONVERTER DESIGN The LIM5050 modules are non-isolated converters operating at a frequency between 500 kHz and 600 kHz. The control circuitry uses average current mode control to achieve a wide bandwidth with little or no overshoot over a wide range of loads. These converters are specifically designed to accommodate loads with a negative impedance such as those presented by Interpoint DC/DC converters with a constant power consumption. PARALLEL OPERATION: UP TO 10 MODULES When the overload condition forces the output voltage to drop the maximum current delivered falls from approximately 1.9 amps to less than 1.5 amps. This feature keeps the short circuit dissipation low and forces the output voltage to collapse rapidly thereby preventing operation in an abnormal condition. Combined with the “Power Ready” signal (see below), this foldback of the output current prevents power cycling of the downstream converters. POWER READY SIGNAL To avoid high current surges during power up, the interface module has a signal intended to connect to the inhibit lines of Interpoint converters to keep these converters turned off until the interface module’s output exceeds approximately 13 volts thereby assuring that, in an overload condition, the converters powered by the interface module will shut off before the power ready signal turns them off. This feature prevents repeated limit cycling in an overload condition. INHIBIT The LIM Series modules have an open collector TTL compatible inhibit terminal that can be used to disable power conversion, resulting in a very low quiescent input current and no generation of switching noise. Up to 10 LIM Series modules can be paralleled for increased power. Current sharing is typically within 2%. OVERLOAD AND CURRENT LIMIT Current overload protection is accomplished by monitoring the output current resulting in a constant current mode when the load exceeds approximately 125% of rated load at full output voltage. Future offerings are planned for the LIM Series of modules. Please contact your Interpoint representative listed in Section A5, for more details. B6-13 LIM SERIES 50 - 250 WATT LINE INTERFACE MODULE ABSOLUTE MAXIMUM RATINGS Input Voltage • 40 to 72 VDC Output Power • 50 watts Lead Soldering Temperature (10 sec per lead) • 300°C Storage Temperature Range (Case) • –65°C to +150°C RECOMMENDED OPERATING CONDITIONS Input Voltage Range • 40 to 72 VDC continuous Case Operating Temperature (Tc) • –55°C to +125°C full power • –55°C to +135°C absolute MODEL NUMBERING KEY Base Model Input Voltage LIM 50 50 / 883 Output Power Screening (Standard screening has no designator in this position.) B6-14 INHIBIT Inhibit: TTL Open Collector • Logic low (output disabled) • Referenced to input common • Logic high (output enabled) 287311-001-DTS Rev A DQ# 3005 All technical information is believed to be accurate, but no responsibility is assumed for errors or omissions. Interpoint reserves the right to make changes in products or specifications without notice. LIM Series, LIM5050, and LIM50250 are trademarks of Interpoint. Copyright © 1999 Interpoint. All rights reserved. CASES CASE E Squared corner and dot on top of case indicate pin one. CASE E BOTTOM VIEW See Figures 16 – 18 for pin configurations. 1.130 max (28.70) Materials Header Cold Rolled Steel/Nickel/Gold Cover Kovar/Nickel (SMHF Series Cold Rolled Steel/Nickel/Gold) Pins #52 alloy/Gold compression glass seal Case dimensions in inches (mm) Tolerance ±0.005 (0.13) for three decimal places ±0.01 (0.3) for two decimal places unless otherwise specified 1.460 max (37.08) CAUTION Heat from reflow or wave soldering may damage the device. Solder pins individually with heat application not exceeding 300°C for 10 seconds per pin. FIGURE 15: CASE E MAXIMUM DIMENSIONS BOTTOM VIEW CASE E1 MHF+ Series Single and Dual: Screening – Standard, ES, or 883 MHF Series and LIM5050 Module: Screening – Standard or ES SMHF Series Single and Dual and SLIM5050 Module: Screening – Space Standard, H, or K HR120 Series: No screening options Seam Seal Projection Weld Squared corner and dot on top of case indicate pin one. 0.960 (24.38) 1 2 3 4 5 0.030 dia. (0.76) 0.205 (5.21) 0.000 0.25 (6.35) 0.000 0.330 max (8.38) 0.25 (6.35) 0.000 0.330 max (8.38) 7 6 0.505 (12.83) 0.705 (17.91) 0.905 (22.99) 1.105 (28.07) 8 0.160 (4.06) 0.000 FIGURE 16: CASE E1 Note: Although every effort has been made to render the case drawings at actual size, variations in the printing process may cause some distortion. Please refer to the numerical dimensions for accuracy. B8-10 CASES Squared corner and dot on top of case indicate pin one. CASE G BOTTOM VIEW Flanged package See Figures 25 - 27 for pin configuration CASE G Materials Header Cold Rolled Steel/Nickel/Gold Cover MHF+ Series and FMH Filter Kovar/Nickel SMHF Cold Rolled Steel/Nickel Pins #52 alloy (all cases) compression glass seal 1.130 max (28.70) Case dimensions in inches (mm) Tolerance ±0.005 (0.13) for three decimal places ±0.01 (0.2) for two decimal places unless otherwise specified 2.005 max (50.93) CAUTION Heat from reflow or wave soldering may damage the device. Solder pins individually with heat application not exceeding 300°C for 10 seconds per pin. Flange Thickness: 0.047 (1.19) FIGURE 24: CASE G MAXIMUM DIMENSIONS BOTTOM VIEW CASE G1 Flanged cases: Designator required in Case Option position of model number MHF+ Series Single and Dual, LIM5050 Module: Screening – Standard, ES, or 883 SMHF Series, SLIM5050 Module: Screening – Space Standard, H, or K Projection Weld Squared corner and dot on top of case indicate pin one. 0.960 (24.38) 1 4 5 0.128 dia (3.25) 1.590 (40.39) 1.105 (28.07) 6 0.905 (22.99) 0.000 7 0.705 (17.91) 8 0.140 (3.56) 0.25 (6.35) 0.000 0.330 max. (8.38) 0.25 (6.35) 0.000 3 0.560 (14.22) 0.160 (4.06) 0.000 0.330 max. (8.38) 2 0.505 (12.83) 0.030 dia. (0.76) 0.205 (5.21) Seam Seal FIGURE 25: CASE G1 Note: Although every effort has been made to render the case drawings at actual size, variations in the printing process may cause some distortion. Please refer to the numerical dimensions for accuracy. B8-15 QA SCREENING 125°C PRODUCTS 125°C PRODUCTS TEST (125°C Products) STANDARD /ES /883 (Class H)* PRE-CAP INSPECTION Method 2017, 2032 yes yes yes TEMPERATURE CYCLE (10 times) Method 1010, Cond. C, -65°C to 150°C Method 1010, Cond. B, -55°C to 125°C no no no yes yes no CONSTANT ACCELERATION Method 2001, 3000 g Method 2001, 500 g no no no yes yes no BURN-IN Method 1015, 160 hours at 125°C 96 hours at 125°C case (typical) no no no yes yes no FINAL ELECTRICAL TEST MIL-PRF-38534, Group A Subgroups 1 through 6: -55°C, +25°C, +125°C Subgroups 1 and 4: +25°C case no yes no yes yes no HERMETICITY TESTING Fine Leak, Method 1014, Cond. A Gross Leak, Method 1014, Cond. C Gross Leak, Dip (1 x 10-3) no no yes yes yes no yes yes no FINAL VISUAL INSPECTION Method 2009 yes yes yes Test methods are referenced to MIL-STD-883 as determined by MIL-PRF-38534. *883 products are built with element evaluated components and are 100% tested and guaranteed over the full military temperature range of –55°C to +125°C. Applies to the following products MOR Series MHD Series MFLHP Series MHV Series MFL Series MHF+ Series MHP Series MHF Series** MTR Series MGA Series MQO Series** MSA Series MGH Series MCH Series FM-704A EMI Filter FMD**/FME EMI Filter FMC EMI Filter FMH EMI Filter FMGA EMI Filter FMSA EMI Filter HUM Modules** LCM Modules** LIM Modules **MFLHP Series, MQO Series, MHF Series, FMD EMI Filters, Hum Modules, and LCM Modules do not offer ‘883” screening. C2-10