mic2111 single - phase, multi - mode, high - performance, step - down pwm controller preliminary micrel inc. ? 2180 fortune drive ? san jose, ca 95131 ? usa ? tel +1 (408) 944 - 0800 ? fax + 1 (408) 474 - 1000 ? http://www.micrel.com march 11, 2014 revision 1.0 general description micrel?s mic2111 is a programmable - frequency, valley - current/voltage - mode pwm controller that provides the control and protection features necessary for a high - current, step - down dc - to - dc converter. the mic2111 is compatible with power devices and drivers which use current sensing across the inductor. mic2111 can provide single tri - state or dual non - tri - state pwm logic signals to work with either power - stage mo dules or discrete driver mosfets. mic2111 has precision enable and power good (pg) functions for sequencing of multiple power supply. the mic2111 frequency can be programmed from 200khz to 2mhz to optimize system size and system efficiency. the device oper ates in power - saving mode at light loads by reducing the switching frequency. the device can be configured to operate ou tside audio range when the external power stage is configured for light load mode. the mic2111 uses differential current sensing for b etter current - limit accuracy and also includes a dedicated differential amplifier for remote output sensing to provide a more accurate output . mic2111 has a high - gain transconductance amplifier for loop compensation. external slope compensation can be adde d through a resistor to avoid sub - harmonic oscillations. the mic2111 has programmable ocp, ovp, and thermal otp protections as well as a dedicated fault pin for accurate system startup/stop in fault conditions. the mic2111 is available in a 20 - pin 3mm 3m m tqfn package and has a junction temperature range of ? 40 c to +125 c. datasheets and support documentation are available on micrel?s web site at : www.micrel.com . features ? single 3.3v or 5v supply ? supports load curre nts more than 50a ? programmable valley - current/voltage - mode pwm architecture ? 3.3v logic pwm outputs compatible with power - stage modules and drmos modules ? single tri - state pwm output ? programmable switching frequency: 200khz to 2mhz. ? differential remote sen sing for output voltage and inductor current ? 0.6v reference voltage with total 1% accuracy for output ? adjustable soft - start/soft - stop and pre - biased safe startup. ? supports light load and outside audio modes ? programmable slope compensation and loop compensation ? enable input, power - good (pg) output for sequencing ? programmable ocp, ovp, otp, and dedicated fault pin for system safe startup/stop ? internal thermal shutdown and uvlo ? ? 40 c to +125 c junction temperature range ? available in 20 - pin 3mm 3mm tqfn package applications ? servers and work stations ? routers, switches and networking/telecom infrastructure ? printers, scanners, graphics and video cards ordering information part number switching frequency junction temperature range current - sense gain package lead finish MIC2111AYML 200khz to 2mhz ? 40 c to +125c 1 v/v 20- pin 3mm 3mm tqfn pb - free mic2111byml 200khz to 2mhz ? 40 c to +125c 30 v/v 20- pin 3mm 3mm tqfn pb - free
micrel, inc. mic2111 march 11, 2014 2 revision 1.0 t ypical application mic2111b and drmos for a 2 5 a synchronous buck converter pin configuration 20- pin 3mm 3mm tqfn (top view) micrel, inc. 2180 fortune drive san jose, ca 95131 usa tel +1 (408) 944 - 0800 fax +1 (408) 474- 1000 web http://www.micrel.com micrel makes no representations or warranties with respect to the accuracy or completeness of the information furnished in th is data sheet. this information is not intended as a warranty and micrel does not assume responsibility for its use. micrel reserv es the right to change circuitry, specifications and descriptions at any time without notice. no license, whether express, implied, arising by estoppel or otherwise, to any intellectual property rights is granted by this document. except as provided in m icrel?s terms and conditions of sale for such products, micrel assumes no liability whatsoever, and micrel disclaims any express or implied warranty relating to the sale and/or use of micrel products including liability or warranties relating to fitness fo r a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right . ? 2014 micrel, incorporated.
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