DEMO CIRCUIT DC872A LTC4213 QUICK START GUIDE LTC4213 Electronic Circuit Breaker DESCRIPTION Demonstration circuit DC872A features the LTC4213 Board allows evaluation of the LTC4213 over its full op- NoRsense Electronic Circuit Breaker, which provides erating voltage range, at all three over-current protection over-current protection without a sense resistor. The levels and with ON and RESET functionality. Design files for this circuit board are available. Call the LTC factory. , LTC and LT are registered trademarks of Linear Technology Corporation. ThinSOT and PowerPath are trademarks of Linear Technology Corporation. PERFORMANCE SUMMARY SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS V Supply Voltage Range 2.6 6.0 V CC V SENSEP Voltage Range V V 0 6.0 V SENSEP SENSEP CC V V V Rising 1.8 2.1 2.23 V CC(URLR) CC Undervoltage Lockout Release CC V Circuit Breaker Trip Voltage V = V , I = 0V 22.5 25 23 mV CB SENSEP CC OSEL V =V -V at slow comparator Trips V = V I = Floated 45 50 55 CB SENSEP SENSEN SENSEP CC, OSEL V = V I = V 90 100 110 SENSEP CC, OSEL CC V Circuit Breaker Trip Voltage V = V , I = 0V 100 mV CB(FAST) SENSEP CC OSEL V =V -V at fast comparator V = V I = Floated 175 mV CB(FAST) SENSEP SENSEN SENSEP CC, OSEL Trips V = V I = V 325 mV SENSEP CC, OSEL CC I Gate Pin Pull Up Current V = 0V, 50 -100 -150 A GATE(UP) GATEN I Gate Pin Pull Down Current V =1V, D=V -V =200 mV, 10 40 80 mA GATE(DN) ON SENSEP SENSEN V = 8V GATE V ON Pin High Threshold ON Rising, Gate Pulls Down 0.76 0.8 0.84 V ON(TH) V ON Pin Reset Threshold ON Falling, Fault Reset, Gate Pulled Down 0.36 0.4 0.44 V ON(RST) OPERATING PRINCIPLES The LTC4213 is an Electronic Circuit Breaker that has a 0V One of three Circuit Breaker thresholds, 25mV, 50mV, or to 6.0V operating range and a 10V absolute maximum 100mV is selected by connecting ISEL pin to GND, leav- operating voltage for the V pin. In low voltage applica- ing it floating, or connecting to Vcc, respectively. The cor- CC tions where the rail voltage is lower than 2.6V, the V pin responding fast comparator thresholds are 100mV, CC must have a separate supply. 175mV, and 325mV. The circuit Breaker function is based on sensing the volt- When the ON pin signal increases above 0.8V, the device age across the drain and source of an external N- starts up and the GATE pulls up with a 100A current channel MOSFET. The LTC4213 provides dual level over- source. When the ON pin signal drops below 0.76V, the current protection. The slow comparator has 15s re- GATE pulls down. To reset a circuit breaker fault, the ON sponse time while the fast comparator trips in 1s. pin must go below 0.4V. 5 4 3 2 1 REVISION HISTORY This circuit is proprietary to Linear Technology and supplied for use with Linear Technology parts. ECO REV DESCRIPTION DATE APPROVED Customer Notice: Linear Technology has made a best effort to 2 PROD 06/22/05 design a circuit that meets customer-supplied specifications however, it remains the customers responsibility to verify proper and reliable operation in the actual application, Component substitution and printed circuit board layout may significantly affect circuit performance or reliability. Contact Linear D Applications Engineering for assistance. D Q1 E1 E7 Si4466DY 8 3 VIN VOUT 7 2 0V - 6V 0V-6V 3.5A 6 1 C2 D2 C3 5 100uF VCC 100uF SMAJ6.0A OPT VCC >/ = VIN R4 1K VCC >/ = 2.3V VCC U1 LTC4213CDDB C E2 R3 33 R5 C VCC 10K 8 D1 VCC VCC RED 2.3V - 6.0V C1 R1 10uF 1 READY READY 16V 18.2K E6 2 ON EXT ON GND E3 JP2 R2 E5 ON from Vcc JP1 10K 1 GND 100mV 2 2 50mV E4 3 ON from EXT 4 25mV B B UNLESS OTHERWISE SPECIFIED CONTRACT NO. 1630 McCarthy Blvd. DIMENSIONS ARE IN INCHES Milpitas, CA 95035 TOLERANCE ON ANGLE - - - Phone: (408)432-1900 2 PLACES - - - 3 PLACES - - - APPROVALS DATE Fax: (408)434-0507 TECHNOLOGY INTERPRET DIM AND TOL DRAWN PER ASME Y14.5M -1994 MEI 12/02/04 TITLE CHECKED SCH, LTC4213CDDB, FAST CIRCUIT BREAKER A THIRD ANGLE PROJECTION A APPROVED ENGINEER SIZE CAGE CODE DWG NO REV DESIGNER DC872A A 2 Wednesday, April 26, 2006 DO NOT SCALE DRAWING SCALE: FILENAME: 872A-2.DSN 1 NONE SHEET 1 OF 5 4 3 2 1 1 3 2 1 7 SENSEP 3 ISEL 5 4 GATE 4 GND 6 SENSEN 1 2