MIC2342-2YTQ Micrel Inc, MIC2342-2YTQ Datasheet
MIC2342-2YTQ
Specifications of MIC2342-2YTQ
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MIC2342-2YTQ Summary of contents
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... General Description The MIC2342 is a dual-slot power controller supporting the power distribution requirements for Peripheral Component Interconnect Express (PCI Express systems. The MIC2342 provides complete power control support for two PCI Express slots, including the 3.3VAUX defined by the PCI Express standards. Support for the 12V, 3 ...
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... Micrel, Inc. Ordering Information Part Number Latch Off MIC2342–2YTQ MIC2342R–2YTQ (1) MIC2342–3YTQ MIC2342R–3YTQ (1) MIC2342–5YTQ MIC2342R–5YTQ Note: 1. Contact factory for availability June 2008 12V and 3V Fast-Trip Auto-Retry Thresholds 100mV (1) 150mV (1) Disabled 2 MIC2342/2342R 3.3VAUX Nominal Package Current Limit ...
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... Micrel, Inc. Typical Application June 2008 3 MIC2342/2342R M9999-062008-B ...
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... Micrel, Inc. Pin Configuration June 2008 4 MIC2342/2342R M9999-062008-B ...
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... Slot A. Pin 32 is the (+) Kelvin-sense connection to the supply side of the sense resistor for 12V Slot B. These two pins must ultimately connect to each other as close as possible at the MIC2342 controller in order to eliminate any IR drop between these pins. An undervoltage lockout circuit (UVLO) prevents the switches from turning on while this input is lower than its lockout threshold voltage ...
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... UVLO circuit prevents turn-on of the external 3.3VAUX supply until the voltage at the VSTBY[A/B] pins is higher than the V Both pins must be externally connected together at the MIC2342 controller. 3.3VAUX[A/B] Outputs to PCI Express Card Slots: These outputs connect the 3.3AUX pin of the PCI Express connectors to VSTBY[A/B] via internal 0.4-Ω ...
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... VSTBY[A]. These inputs can be connected to the PRNST#1 or PRNST#2 pins on a PCIe connector to indicate to the MIC2342 that a PCIe plug-in card is present and firmly mated. Internally, the MIC2342’s +12VGATE[A/B], +3VGATE[A/B], and 3VAUX[A/B] gate drive circuits are gated with the MIC2342’ ...
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... To de-assert this signal output, please follow instructions provided on /FAULT_MAIN[A/B] and /FAULT_AUX[A/B] output pin descriptions. 3 Pins, IC Ground Connections: Tie directly to the system’s analog GND plane directly at the device. Reserved: Make no external connections to these pins. 8 MIC2342/2342R M9999-062008-A ...
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... VSTBY[A/B]...........................................3.0V to 3.6V )........................ 0° 70° .................................... 125°C J TQFP (θ )................................................. 76.8°C/W JA Min Typ 1.8 0.6 2 2.5 2.2 2.9 2.8 50 180 10.5 10.2 2.8 2.7 2.8 2 MIC2342/2342R Max Units 2 2. 10.8 V 2 1.5 µ M9999-062008-A ...
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... V > V 3VIN 3VSENSE V – V 12VIN 12VSENSE V – V 3VIN 3VSENSE V – V 12VIN 12VSENSE V – V 3VIN 3VSENSE MIC2342-2YTQ Only V – V 12VIN 12VSENSE V – V 3VIN 3VSENSE VSTBY = VSTBY[A/B] = +3.3V; 12VIN[A/B] = OFF; 3VIN[A/B] = OFF VSTBY = VSTBY[A/B] = +3.3V; 12VIN[A/B] = OFF; 3VIN[A/B] = OFF Min Typ 12VIN – ...
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... OUT[A/ 1.65V AUX[A/B] 11 Min Typ 100 ° 100 ° 100 °C J 140 130 160 150 0.84 to CFILTER time-out 0.7 0.375 160 150 430 MIC2342/2342R Max Units µA 5 kΩ µA Ω 0 °C °C °C ° 0.975 Ω 0 Ω Ω M9999-062008-B ...
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... VAUX[A/B] = 0V, VSTBY[A/B] = +3.3V MIC2342-2YTQ CFILTER[A/B] = OPEN (5) V –V = 140mV IN SENSE MIC2342-2YTQ CFILTER[A/B] = OPEN (5) V –V = 140mV IN SENSE MIC2342-2YTQ limit to /FAULT_AUX[A/B] output CFILTER CFILTER[A/B] = 50pF V Output Grounded (5) AUX ON[A/B], AUXEN[A/B] = HIGH-to-LOW-HIGH ON[A/B] or AUXEN[A/B] High-to-Low Transition ON[A/B], AUXEN[A/B] = HIGH, 12VOUT[A/B], 3VOUT[A/B], VAUX[A/B] = VALID; CFILTER[A/B] = GND 12 ...
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... SENSE V THFAST V THILIMIT 12VGATE 0V t OFF(12V) Figure 1. 12V Current Limit Response Timing – SENSE V THFAST V THILIMIT 3VGATE 0V t OFF(3V) Figure 2. 3V Current Limit Response Timing Must Trip I AUX(THRESH) May Not Trip OUT(AUX) OUT(AUX) 0 Figure 3. VAUX Current Limit Threshold LIM(AUX) t MIC2342/2342R M9999-062008-B ...
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... Micrel, Inc. June 2008 I SC(TRAN LIM(AUX) I OUT(AUX) t SC(TRAN) 0 Figure 4. VAUX Current Limit Response Timing 14 MIC2342/2342R t M9999-062008-B ...
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... Micrel, Inc. Functional Diagram June 2008 MIC2342/MIC2342R Block Diagram 15 MIC2342/2342R M9999-062008-B ...
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... Micrel, Inc. Typical Characteristics June 2008 16 MIC2342/2342R M9999-062008-B ...
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... Micrel, Inc. Typical Characteristics (cont.) June 2008 17 MIC2342/2342R M9999-062008-B ...
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... June 2008 +12VOUT[A/B] and +3VOUT[A/B] Start-Up Cycles All four of the MIC2342’s +12V and +3V gate drive circuits have been designed to drive the gates of external power MOSFETs. The +12V gate drive circuits have been designed to drive P-channel MOSFETs and the +3V gate drive circuits are intended to drive N- channel MOSFETs ...
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... ISSN channel power MOSFET) for LOAD(12VOUT[A/B]) INRUSH(3VOUT[A/B]) and V for V . UVTH(3V) UVTH(12V) For example Si4420BDY n-channel power MOSFET is used with the MIC2342 to control inrush currents at 3VOUT[A/B], its C is approximately 4100pF at V ISSN 3V. The 3VGATE[A/B] pin voltage rate of change is given by 3VGATE[A/B ] GATE(3VCHA RGE) ...
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... V LOAD(12VOUT[A/B]) UVTH(3V) Even though individual internal “Power Good” flags may be asserted, the conditions under which the MIC2342’s external /PWRGD[A/B] and /DLY_PWRGD[A/B] digital outputs are asserted is described in the section labeled “/PWRGD[A/B] and /DLY_PWRGD[A/B] Digital Outputs.” Power-Down Cycle ...
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... MAIN supply inputs move below their respective UVLO thresholds, VAUX[A/B] will still function as long as VSTBY[A/B] is present. Prior to standby mode, ONA and ONB inputs should be de-asserted or the MIC2342 will assert the /FAULT_MAIN[A/B] and /INT output signals undervoltage condition on the MAIN supply inputs is detected ...
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... Once the internal digital filter delay counter terminates, the circuit breaker trips off the previous case, the MIC2342 latches off and the MIC2342R initiates the auto-retry delay counter to count up to 820ms before attempting another power-up cycle. 22 MIC2342/2342R ...
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... Plug-in Card Retention Switch Inputs Two pins on the MIC2342 are available for use as card retention switch inputs, /CRSW[A/B]. These pins are internally pulled-up by 45kΩ resistors to VSTBY and prevent the enabling of all gate drive circuits on 12GATE[A/B], 3VGATE[A/B], and VAUX[A/B] unless these input pins are asserted LOW ...
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... Figure 8. State Diagrams for /PWRGD[A/B] and /DLY_PWRGD[A/B] June 2008 SYSPWRGD Digital Output SYSPWRGD is an open-drain, asserted active-HIGH digital output provided by the MIC2342 for additional slot status information to the service or system processor. This output is normally connected by an external 10kΩ resistor local logic supply. ...
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... Table 1. SYSPWRGD Truth Table are already asserted after POR, the corresponding /CRSW[A/B] control signal should be used to enable the slot’s gate drive circuits to initiate a power-up sequence. For example, in order for the MIC2342/MIC2342R to switch on the VAUX supply for either slot, the pins (/CRSW[A/B], ...
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... Micrel, Inc. Figure 9. MIC2342 Output Signals’ Shutdown Responses During AUX and MAIN Overcurrent Faults June 2008 26 MIC2342/2342R M9999-062008-B ...
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... AND its corresponding C timeout or the digital filter delay has expired, OR • The slow VAUX[A/B] OC circuit breaker has tripped AND the Slot[A/B] die temperature is higher than 140°C, OR • The MIC2342’s global die temperature is higher than 160°C signals. Please see /FAULT_AUX[A/B] ...
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... In this case, the application circuits must be sturdy enough to operate up to approximately 1.25x the steady- state hot swap load currents. For example, if one of the 12V slots of the MIC2342 circuit must pass a minimum hot swap load current of 1.5A without nuisance trips, R should be set to: ...
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... PCBs. Figure 12. 4-Wire Kelvin Sense Connections for R June 2008 Finally, the use of Figure 13. Current Limit Sense Filter for Noisy Systems SENSE 29 MIC2342/2342R M9999-062008-B ...
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... Micrel, Inc. Figure 14. Suggested PCB Layout for Sense Resistor, Power MOSFET, and Capacitors June 2008 30 MIC2342/2342R M9999-062008-B ...
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... Series www.vishay.com/docswsl_30100.pdf (203) 452-5664 “OARS” Series www.irctt.com/pdf_files/OARS.pdf “LR” Series www.irctt.com/pdf_files/LRC.pdf second source to “WSL” (828) 264-8861 Table 2. MOSFET and Sense Resistor Vendors 31 MIC2342/2342R Package Contact information SO-8 SO-8 SO-8 SO-8 www.siliconix.com PowerPAK SO-8 (203) 452-5664 PowerPAK SO-8 ...
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... Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully June 2008 48-Pin TQFP (T) indemnify Micrel for any damages resulting from such use or sale. © 2007 Micrel, Incorporated. 32 MIC2342/2342R M9999-062008-B ...