EVALUATION KIT AVAILABLE Click here for production status of specific part numbers. MAX15108A High-Efficiency, 8A, Current-Mode Synchronous Step-Down Switching Regulator General Description Features The MAX15108A high-efficiency, current-mode, synchronous Continuous 8A Output Current step-down switching regulator with integrated power Efficiency Up to 96% switches delivers up to 8A of output current. The regulator 1% Accuracy Over Load, Line, and Temperature operates from 2.7V to 5.5V and provides an output voltage from 0.6V up to 95% of the input voltage, making Operates from a 2.7V to 5.5V Supply the device ideal for distributed power systems, portable Adjustable Output from 0.6V to 0.95 x V IN devices, and preregulation applications. Programmable Soft-Start The IC utilizes a current-mode control architecture with a Safe Startup into Prebiased Output high gain transconductance error amplifier. The current- External Reference Input mode control architecture facilitates easy compensation design and ensures cycle-by-cycle current limit with fast 1MHz Switching Frequency response to line and load transients. Stable with Low-ESR Ceramic Output Capacitors The low R integrated switches ensure high DS(ON) Forced PWM Mode efficiency at heavy loads while minimizing critical Enable Input and Power-Good Output for Power- inductance, making the layout design a much simpler task Supply Sequencing with respect to discrete solutions. The ICs simple layout and footprint assures first-pass success in new designs. Cycle-by-Cycle Overcurrent Protection The regulator features a 1MHz, factory-trimmed fixed- Fully Protected Features Against Overcurrent and frequency PWM mode operation. The high switching Overtemperature frequency, along with the PWM current-mode architecture Input Undervoltage Lockout allows for a compact, all ceramic capacitor design. 20-Bump (4 x 5 Array), 2.5mm x 2mm, WLP Package The IC features a capacitor-programmable soft-start to reduce input inrush current. Internal control circuitry ensures safe-startup into a prebiased output. Power Typical Operating Circuit sequencing is controlled with the enable input and power- good output. OUTPUT LX The IC is available in a 20-bump (4 x 5 array), 2.5mm x 2mm, WLP package and is fully specified over the -40C 2.7V TO EN PGND 5.5V to +105C temperature range. IN Applications MAX15108A FB Distributed Power Systems DDR Memory INX Base Stations COMP Portable Devices PGOOD Notebook Power Server Power SS Ordering Information appears at end of data sheet. 19-6702 Rev 2 1/20MAX15108A High-Efficiency, 8A, Current-Mode Synchronous Step-Down Switching Regulator Absolute Maximum Ratings IN, PGOOD to PGND ..............................................-0.3V to +6V Continuous Power Dissipation (T = +70C) BOARD LX to PGND................................................-0.3V to (V + 0.3V) WLP (derate 31.7mW/C above T = +70C).......1.27W IN BOARD LX to PGND.................................... -1V to (V + 0.3V) for 50ns Operating Temperature Range ......................... -40C to +105C IN EN, COMP, FB, SS to PGND .....................-0.3V to (V + 0.3V) Operating Junction Temperature (Note 2) .......................+125C IN Continuous LX Current (Note 1)............................. -12A to +12A Storage Temperature Range ............................ -65C to +150C Output Short-Circuit Duration ....................................Continuous Soldering Temperature (reflow) (Note 3) .........................+260C 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. Note 1: LX has internal clamp diodes to PGND and IN. Do not exceed the power dissipation limits of the device when forward biasing these diodes. Note 2: Limit the junction temperature to +125C for continuous operation at full current. Note 3: The WLP package is constructed using a unique set of package techniques that impose a limit on the thermal profile the device can be exposed to during board-level solder attach and rework. This limit permits only the use of the solder profiles recommended in the industry-standard specification JEDEC 020A, paragraph 7.6, Table 3 for IR/VPR and convection reflow. Preheating is required. Hand or wave soldering is not allowed. (Note 4) Package Thermal Characteristics WLP Junction-to-Ambient Thermal Resistance ( ) .......31.5C/W JA Note 4: 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 considerations, refer to www.maximintegrated.com/thermal-tutorial. Electrical Characteristics (V = 5V, C = 4.7nF, T = T = -40C to +105C. Typical values are at T = +25C, unless otherwise noted.) (Note 4) IN SS A J A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS IN Voltage Range V 2.7 5.5 V IN IN Shutdown Supply Current V = 0V 0.3 3 A EN IN Supply Current I V = 5V, V = 0.75V, not switching 3.4 6 mA IN EN FB V Undervoltage Lockout Threshold LX starts switching, V rising 2.6 2.7 V IN IN V Undervoltage Lockout Hysteresis LX stops switching, V falling 200 mV IN IN ERROR AMPLIFIER Transconductance g 1.4 mS MV Voltage Gain A 90 dB VEA FB Set-Point Accuracy V Over line, load, and temperature 594 600 606 mV FB FB Input Bias Current I -100 +100 nA FB COMP to Current-Sense G 25 A/V MOD Transconductance COMP Clamp Low V = 0.75V 0.93 V FB Compensation RAMP Valley 1 V POWER SWITCHES High-Side Switch Current-Limit I 14 A HSCL Threshold Low-Side Switch Sink 14 A Current-Limit Threshold Low-Side Switch Source 14 A Current-Limit Threshold Maxim Integrated 2 www.maximintegrated.com