EVALUATION KIT AVAILABLE MAX15026 Low-Cost, Small, 4.5V to 28V Wide Operating Range, DC-DC Synchronous Buck Controller General Description Features 4.5V to 28V or 5V 10% Input Supply Range The MAX15026 synchronous step-down controller oper- 0.6V to (0.85 x V ) Adjustable Output ates from a 4.5V to 28V input voltage range and gener- IN ates an adjustable output voltage from 85% of the input Adjustable 200kHz to 2MHz Switching Frequency voltage down to 0.6V while supporting loads up to 25A. Ability to Start into a Prebiased Load The device allows monotonic startup into a prebiased Lossless, Cycle-by-Cycle Valley Mode Current bus without discharging the output and features adap- Limit with Adjustable, Temperature-Compensated Threshold tive internal digital soft-start. Sink-Mode Current-Limit Protection The MAX15026 offers the ability to adjust the switching Adaptive Internal Digital Soft-Start frequency from 200kHz to 2MHz with an external resis- 1% Accurate Voltage Reference tor. The MAX15026s adaptive synchronous rectification Internal Boost Diode eliminates the need for an external freewheeling Schottky diode. The device also utilizes the external Adaptive Synchronous Rectification Eliminates External Freewheeling Schottky Diode low-side MOSFETs on-resistance as a current-sense Hiccup-Mode Short-Circuit Protection element, eliminating the need for a current-sense resis- tor. This protects the DC-DC components from damage Thermal Shutdown during output overloaded conditions or output short- Power-Good Output and Enable Input for Power Sequencing circuit faults without requiring a current-sense resistor. Hiccup-mode current limit reduces power dissipation 5% Accurate Enable Input Threshold during short-circuit conditions. The MAX15026 includes AEC-Q100 Qualified (MAX15026B) a power-good output and an enable input with precise Ordering Information turn-on/turn-off threshold, which can be used for input supply monitoring and for power sequencing. PART TEMP RANGE PIN-PACKAGE Additional protection features include sink-mode cur- MAX15026BETD+ -40C to +85C 14 TDFN-EP* rent limit and thermal shutdown. MAX15026BETD/V+T -40C to +85C 14 TDFN-EP* Sink-mode current limit prevents reverse inductor cur- MAX15026CETD+ -40C to +85C 14 TDFN-EP* rent from reaching dangerous levels when the device is MAX15026BATD+ -40C to +125C 14 TDFN-EP* sinking current from the output. MAX15026CATD+ -40C to +125C 14 TDFN-EP* The MAX15026 is available in a space-saving and ther- MAX15026DATD+ -40C to +125C 14 TDFN-EP* mally enhanced 3mm x 3mm, 14-pin TDFN-EP pack- +Denotes a lead(Pb)-free/RoHS-compliant package. age. The MAX15026 operates over the extended -40C to +85C and automotive -40C to +125C temperature *EP = Exposed pad. T = Tape and reel. ranges. /V denotes an automotive qualified part. MAX15026D recommended for new designs. The MAX15026C is designed to provide additional mar- gin for break-before-make times. Pin Configuration The MAX15026B/MAX15026C provide a soft-stop TOP VIEW feature to ramp down the output voltage at turn-off. The soft-stop function is disabled in the MAX15026D. IN 1 14 DH + Applications V 2 13 LX CC Set-Top Boxes PGOOD312 BST LCD TV Secondary Supplies EN 4 11 DL MAX15026 Switches/Routers LIM 5 10 DRV Power Modules COMP69 GND *EP DSP Power Supplies FB78 RT Points-of-Load Regulators TDFN (3mm x 3mm) *EP = EXPOSED PAD. For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maximintegrated.com. 19-4108 Rev 5 11/12MAX15026 Low-Cost, Small, 4.5V to 28V Wide Operating Range, DC-DC Synchronous Buck Controller ABSOLUTE MAXIMUM RATINGS IN to GND...............................................................-0.3V to +30V DRV Input Current.............................................................600mA BST to GND............................................................-0.3V to +36V PGOOD Sink Current ............................................................5mA LX to GND .................................................................-1V to +30V Continuous Power Dissipation (T = +70C) (Note 1) A EN to GND................................................................-0.3V to +6V 14-Pin TDFN-EP, Multilayer Board PGOOD to GND .....................................................-0.3V to +30V (derate 24.4mW/C above +70C)..............................1951mW BST to LX..................................................................-0.3V to +6V Operating Temperature Range DH to LX ................................................-0.3V to (V + 0.3V) MAX15026B/CETD+, MAX15026BETD/V+.......-40C to +85C BST DRV to GND .............................................................-0.3V to +6V MAX15026B/C/DATD+ ...................................-40C to +125C DL to GND ................................................-0.3V to (V + 0.3V) Junction Temperature......................................................+150C DRV V to GND...............-0.3V to the lower of +6V and (V + 0.3V) Storage Temperature Range .............................-60C to +150C CC IN All Other Pins to GND.................................-0.3V to (V + 0.3V) Lead Temperature (soldering, 10s) .................................+300C CC V Short Circuit to GND...........................................Continuous Soldering Temperature (reflow) .......................................+260C CC Note 1: Dissipation wattage values are based on still air with no heatsink. Actual maximum power dissipation is a function of heat extraction technique and may be substantially higher. Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board. For detailed information on package thermal consid- erations, refer to www.maximintegrated.com/thermal-tutorial. Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (V = 12V, R = 27k, R = 30k, C = 4.7F, C = 1F, T = -40C to +85C (MAX15026B/CETD+, MAX15026BETD/V+), IN RT LIM VCC IN A T = T = -40C to +125C (MAX15026B/C/DATD+), unless otherwise noted. Typical values are at T = +25C.) (Note 2) A J A CONDITIONS PARAMETER SYMBOL MIN TYP MAX UNITS GENERAL 4.5 28 Input Voltage Range V V IN V = V = V 4.5 5.5 IN CC DRV Quiescent Supply Current V = 0.9V, no switching 1.75 2.75 mA FB Shutdown Supply Current I EN = GND 290 500 A IN SBY Enable to Output Delay 480 s V High to Output Delay EN = V 375 s CC CC V REGULATOR CC 6V < V < 28V, I = 25mA IN LOAD Output Voltage V 5.0 5.25 5.5 V CC V = 12V, 1mA < I < 70mA IN LOAD V Regulator Dropout V = 4.5V, I = 70mA 0.28 V CC IN LOAD V Short-Circuit Output Current V = 5V 100 200 300 mA CC IN V Undervoltage Lockout V V rising 3.8 4.0 4.2 V CC CC UVLO CC V Undervoltage Lockout CC 400 mV Hysteresis ERROR AMPLIFIER (FB, COMP) FB Input Voltage Set-Point V 585 591 597 mV FB FB Input Bias Current I V = 0.6V -250 +250 nA FB FB FB to COMP Transconductance g I = 20A 600 1200 1800 S M COMP Amplifier Open-Loop Gain 80 dB Amplifier Unity-Gain Bandwidth Capacitor from COMP to GND = 50pF 4 MHz V Minimum Voltage 160 mV COMP-RAMP COMP Source/Sink Current I V = 1.4V 50 80 110 A COMP COMP 2 Maxim Integrated