MIC2040/2041 Micrel MIC2040/2041 Single Channel Low Voltage Power Distribution Switch General Description Features The MIC2040 and MIC2041 are high side MOSFET switches 75m max. on-resistance optimized for general purpose power distribution applications 0.8V to 5.5V operating range that require circuit protection. The devices switch up to 5.5V Adjustable current limit and as low as 0.8V while offering both programmable current Up to 1.5A continuous output current limiting and thermal shutdown to protect the device and the Short circuit protection with thermal shutdown load. A fault status output is provided in order to detect Circuit breaker mode (MIC2041) overcurrent and thermal shutdown fault conditions. Both Fault status flag devices employ soft start circuitry to minimize the inrush Undervoltage lockout current in applications that employ highly capacitive loads. Output MOSFET reverse current flow block when Additionally, the MIC2040/41 is suited for multi-port USB disabled applications to satisfy upstream/downstream power require- Very fast reaction to short-circuits ments. Low quiescent current The MIC2041 features a auto-reset circuit breaker mode that latches the output off upon detecting an overcurrent condition Applications lasting more than 28ms. The output is reset by removing or Docking stations reducing the load. Notebook PCs Data sheets and support documentation can be found on PDAs Micrels web site at www.micrel.com. Board hot swap RAID controllers USB peripherals ACPI power distribution Ordering Information Part Number Standard Pb-Free Enable Circuit Breaker Package MIC2040-1BMM MIC2040-1YMM Active-High 10-Pin MSOP MIC2040-2BMM MIC2040-2YMM Active-Low 10-Pin MSOP MIC2041-1BMM MIC2041-1YMM Active-High X 10-Pin MSOP MIC2041-2BMM MIC2041-2YMM Active-Low X 10-Pin MSOP Typical Application C2 MIC2040-1BM V OUT 0.1F 3.3V 1A 6 8,10 VBIAS VOUT +3.3V C3 4.7F Power C LOAD 7, 9 Supply VIN 33F C1 R1 0.1F 1 20k ON/OFF EN Logic IN Controller 2 3 /FAULT UVLOIN (OPEN) OVERCURRENT 5 ILIM R SET GND Note: 340 4 BothV pins (7, 8) must be externally tied together. IN BothV pins (8, 10) must be externally tied together. OUT I = 1A. LIMIT Micrel, Inc. 1849 Fortune Drive San Jose, CA 95131 USA tel + 1 (408) 944-0800 fax + 1 (408) 944-0970 MIC2040/2041 Micrel Pin Configuration EN 1 10 VOUT /FAULT 2 9 VIN UVLOIN 3 8 VOUT GND 4 7 VIN ILIM 5 6 VBIAS MIC2040/MIC2041 10-Pin MSOP (MM) Pin Description Pin Number Pin Name Pin Function 1EN Switch Enable Input: Gate control pin of the output MOSFET available as an active high (1) or active low (2) input signal. 2 /FAULT Fault Status Output: Open drain N-Channel device, active low. This pin indicates an overcurrent, or thermal shutdown condition. For an overcurrent event, /FAULT is asserted if the duration of the overcurrent condition lasts longer than 28ms. 4 GND Ground Connection: Tie to analog ground. 5 ILIM Current Limit Set: A resistor, R , connected to this pin sets the current SET limit threshold as CLF/R , where CLF is the current limit factor specified in SET the electrical characteristics table. For the MIC2040/41, the continuous output current range is 0.25A to 1.5A. 7, 9 VIN Switch Input Supply: The drain of the output MOSFET. The range of input for the switch is 0.8V to 5.5V. These pins must be externally connected together. 8, 10 VOUT Switch Output: The source of the output MOSFET. These pins must be externally connected together. 6 VBIAS Bias Supply Input: This input pin supplies bias to operate the switch with range from 1.6V to 5.5V. When switching voltage (V ) is between 1.6V to IN 5.5V and the use of a single supply is desired, connect VBIAS to VIN externally. 3 UVLOIN Undervoltage Lockout Adjust Input: With this pin left open, the UVLO threshold is internally set to 1.45V. When the switching voltage (V ) is at or IN below 1.6V, connecting an external resistive divider to this input will lower the UVLO threshold. The total resistance must be less than 200k. See Applications Information for further detail. M9999-012004 2 January 2005