MIC2585 Micrel Semiconductor, MIC2585 Datasheet
MIC2585
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MIC2585 Summary of contents
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... The MIC2584 and MIC2585 are dual-channel positive volt- age hot swap controllers designed to facilitate the safe insertion of boards into live system backplanes. The MIC2584 and MIC2585 are available in 16-pin and 24-pin TSSOP packages, respectively. Using a few external discrete com- ponents and by controlling the gate drives of external N- ...
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... R SENSE2 0.020 0. VCC2 SENSE2 VCC1 47k R4 22k 22k 14 /FAULT MIC2585-1 12 CDLY *C5 0.047 F R8 30. OV1 4 OV2 R9 CPOR GND CFILTER 8.06k 0.02 F with respect to V OUT2 Delay = 9.5ms Figure 1. Typical Application Circuit 2 Q1 ...
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... CFILTER 11 14 /FAULT CDLY 12 13 GND MIC2585 24-Pin TSSOP (TS) CC1 and V exceed their CC1 CC2 ), the GATE voltage is adjusted to ensure a constant (50mV) is exceeded for longer than time period , at any point due to fast, TRIPFAST for either device is 100mV. Other fast trip thresholds disabled) ...
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... Circuit Breaker Fault Status (Output): Active-Low, weak pull-up to VCC1 or open-drain. Asserted when the circuit breaker is tripped due to an overcurrent, undervoltage lockout, or overvoltage event. When deasserted, the MIC2585 will initiate a new start cycle by toggling the ON pin. /POR Power-On Reset (Output): Active Low, weak pull-up to VCC1 or open drain. ...
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... MIC2584/2585 Pin Number Pin Number MIC2584 MIC2585 N N N/A 16, 17 March 2005 Pin Name Pin Function OV2, OV1 Overvoltage Detect Inputs: Whenever the threshold voltage (V either input is exceeded, the circuit-breaker is tripped while /FAULT is asserted and the GATE1 and GATE2 outputs are immediately brought low. ...
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MIC2584/2585 Absolute Maximum Ratings All voltages are referred to GND) Supply Voltage ( .......................... –0.3V to 20V CC1 CC2 SENSE1/SENSE2 pins .............................. –0. TRK, ON, DIS1, DIS2, OUT1, OUT2, /POR, /FAULT, PG1, PG2 pins .................. ...
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... PG1, PG2 Output OL Low Voltage (PG1 and PG2 for MIC2585 only) I /FAULT , /POR , PG1, PG2 Active PULLUP Output Pull-up Current (PG1 and PG2 for MIC2585 only) V GATE1 and GATE2 ON/OFF GATEWIN Voltage Window (Tracking enabled) Note 3 AC Parameters t Fast Overcurrent Sense to GATE ...
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... V OUT1 OUT2 (-1) (- OUT2 OUT1 t (-1) (-2) DLY Sequencing/Tracking Mode, TRK = V (- follows V OUT2 OUT1 (- follows V OUT1 OUT2 Figure 5. Sequencing Modes (MIC2585 only TRIPFAST t OCFAST 0.5V V POR t POR V<0.25V or V OUT2 V<0.25V or V OUT1 OUT2 Micrel March 2005 ...
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MIC2584/2585 Typical Characteristics V TRIPSLOW1+ vs. Temperature 5.0V CC1 52 V CC1 2.3V 46 CC1 44 42 -40 - 100 TEMPERATURE ( C) V TRIPSLOW2– ...
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MIC2584/2585 Overvoltage1 vs. Temperature 1. 13.2V CC1 1.24 1. 5.0V CC1 V = 2.3V CC1 1.22 1.21 -40 - 100 TEMPERATURE ( C) FB2 Threshold vs. Temperature 0.81 V =13.2V ...
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... C (optional) March 2005 SENSEx 0.005 V + INx 33k INx 4 – SENSEx VCCx INx GA TEx ON MIC2585 OUTx CDLY FBx DLY CFILTER CPOR 8200pF GND (Not all pins shown for simplicity OUT IRF7822 V + (SO-8) OUTx R LOAD C LOAD V – OUTx 0. ...
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... CC2 = 220 CC1 = V 3.3V CC2 = 2200 220 Micrel Turn-On, Staggered Mode (MIC2585-1BTS CC1 V = 3.3V CC2 C = 47nF DLY OPEN L1 L2 TIME (10ms/div.) Turn-On (Channel CC1 = V 3.3V CC2 = 220 F L1 TIME (2.5ms/div.) ...
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... Turn-On Response (Hot Insert) TIME (5ms/div.) Short-Circuit Crowbar Channel 1 (SCR enabled through a PNP from DIS pin-MIC2585-1BTS) 4.5A peak TIME (25 s/div.) March 2005 CC1 V = 3.3V CC2 C = 250 (SCR enabled through a PNP from DIS pin-MIC2585-1BTS CC1 V = 3.3V CC2 220 Short-Circuit Response 6 ...
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... REF 2 (9) GND 18 (12) FB1 V REF 7 (5) FB2 0.8V 12 CDLY V V CC1 REF 2 CPOR 10 (7) CPOR 0.3V V REF 8 ( REF MIC2584/2585 MIC2585-J + – 10V 50mV + – 10V 50mV + – 100mV + – 100mV + UVLO2 0.8V + – Logic + Glitch Filter – + Glitch Filter – + – ...
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... The MIC2584 and MIC2585 act as a controller for external N-Channel MOSFET devices in which the gate drive is controlled to provide inrush current limiting and output voltage slew rate control during hot swap insertions ...
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... The MIC2585 monitors and detects overvoltage conditions in the event of excessive supply transients at the MIC2585 input(s)/output(s). Whenever the voltage threshold is ex- ceeded at either OV1 or OV2 of the MIC2585, the circuit breaker is tripped and both GATE outputs are immediately brought low. . GATE ...
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... MIC2584/2585 The sequenced output feature is enabled for the MIC2585 by placing a capacitor from CDLY to ground. The –1 option allows for V to follow V OUT2 V to follow V during start-up (See " OUT1 OUT2 grams, Figure 5 "). The sequenced output delay time is determined using the following equation: ...
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... MIC2584/2585 up and power-down independent of the load capacitance of each supply. See " Wiring the TRK pin to either OUT1 or OUT2 of the MIC2585 enables the tracking feature. The OUT1 and OUT2 pins provide output track sensing and are wired directly to the output (source) of the external MOSFET for Channel 1 and Channel 2, respectively ...
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... The MIC2585 can be configured to allow one output to shut off first, followed by the other output. Figure 8 illustrates an example circuit that sequences OUT1 and OUT2 in a first on– ...
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... R13 and higher tolerance for R12, 14.55k and 106.05k , respectively. With only 11.4V available, the voltage sensed at the FB1 pin exceeds V 12.9k . PG1 (MIC2585) signals will transition from LOW to HIGH, 1%. indicating “power is good” given the worse case tolerances of this example. A similar approach should be used for Channel 2. 20 ...
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MIC2584/2585 Input Overvoltage Protection A similar design approach as the previous Undervoltage Detection example is recommended for the overvoltage protection circuitry, resistors R6 and R7 for OV1, in Figure 1. For input overvoltage protection, the first consideration is to ...
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... Channel 2 is used to implement the first on-last off application. Sense Resistor Selection . In the example circuit , the The MIC2584 and MIC2585 use a low-value sense resistor to measure the current flowing through the MOSFET switch (and therefore the load). This sense resistor is nominally set at 50mV/I ...
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MIC2584/2585 the opposite direction. Here, the worst-case maximum cur- rent is found using a 57.5mV trip voltage and a sense resistor that is 3% low in value. The resulting equation is: 57.5mV I LOAD(CONT,MAX) 0.97 R SENSE(NOM ...
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MIC2584/2585 MOSFET Steady-State Thermal Issues The selection of a MOSFET to meet the maximum continuous current is a fairly straightforward exercise. First, arm yourself with the following data: • The value of I LOAD(CONT, MAX.) Sense Resistor Selection question ...
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MIC2584/2585 higher pulsed power without damage than its continuous dissipation ratings would imply. The reason for this is that, like everything else, thermal devices (silicon die, lead frames, etc.) have thermal inertia. In terms related directly to the specification ...
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MIC2584/2585 PCB Layout Considerations Because of the low values of the sense resistors used with the MIC2584/85 controllers, special attention to the layout must be used in order for the device’s circuit breaker function to operate properly. Specifically, the ...
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MIC2584/2585 MOSFET and Sense Resistor Vendors Device types and manufacturer contact information for power MOSFETs and sense resistors is provided in Table 5. Some of the recommended MOSFETs include a metal heat sink on the bottom side of the ...
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MIC2584/2585 Package Information 7.90 (0.311) 7.70 (0.303) MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA + 1 (408) 944-0800 TEL The information furnished by Micrel in this datasheet is believed to be accurate and reliable. However, no ...