MAX1533A/MAX1537A 19-4023 Rev 0 4/06 High-Efficiency, 5x Output, Main Power-Supply Controllers for Notebook Computers General Description Features The MAX1533A/MAX1537A are dual step-down, switch- Fixed-Frequency, Current-Mode Control mode power-supply (SMPS) controllers with synchro- 40/60 Optimal Interleaving nous rectification, intended for main 5V/3.3V power generation in battery-powered systems. Fixed-frequen- Accurate Differential Current-Sense Inputs cy operation with optimal interleaving minimizes input Internal 5V and 3.3V Linear Regulators with ripple current from the lowest input voltages up to the 100mA Load Capability 26V maximum input. Optimal 40/60 interleaving allows the input voltage to go down to 8.3V before duty-cycle Auxiliary 12V or Adjustable 150mA Linear overlap occurs, compared to 180 out-of-phase regula- Regulator (MAX1537A Only) tors where the duty-cycle overlap occurs when the Dual Mode Feedback3.3V/5V Fixed or input drops below 10V. Output current sensing pro- Adjustable Output (Dual Mode) Voltages vides accurate current limit using a sense resistor. Alternatively, power dissipation can be reduced using 200kHz/300kHz/500kHz Switching Frequency lossless inductor current sensing. Versatile Power-Up Sequencing Internal 5V and 3.3V linear regulators power the MAX1533A/MAX1537A and their gate drivers, as well as Adjustable Overvoltage and Undervoltage external keep-alive loads, up to a total of 100mA. When Protection the main PWM regulators are in regulation, automatic 6V to 26V Input Range bootstrap switches bypass the internal linear regulators, providing currents up to 200mA from each linear output. 2V 0.75% Reference Output An additional 5V to 23V adjustable internal 150mA linear Power-Good Output regulator is typically used with a secondary winding to provide a 12V supply. Soft-Shutdown The MAX1533A/MAX1537A include on-board power-up 5A (typ) Shutdown Current sequencing, a power-good (PGOOD) output, digital soft-start, and internal soft-shutdown output discharge Pin Configurations that prevents negative voltages on shutdown. The MAX1533A is available in a 32-pin 5mm x 5mm thin QFN package, and the MAX1537A is available in a 36- TOP VIEW pin 6mm x 6mm thin QFN package. The exposed back- side pad improves thermal characteristics for 32 31 30 29 28 27 26 25 demanding linear keep-alive applications. ON5 FB5 1 24 Applications ON3 2 23 LDO5 2 to 4 Li+ Cells Battery-Powered Devices FSEL 3 22 DL5 Notebook and Subnotebook Computers ILIM3 4 21 PGND PDAs and Mobile Communicators MAX1533A ILIM5 5 20 DL3 Ordering Information REF 6 19 LDO3 GND 7 18 FB3 PART TEMP RANGE PIN-PACKAGE V 8 17 CSL3 CC MAX1533AETJ -40C to +85C 32 Thin QFN 5mm x 5mm MAX1533AETJ+ -40C to +85C 32 Thin QFN 5mm x 5mm 9 101112131415 16 MAX1537AETX -40C to +85C 36 Thin QFN 6mm x 6mm MAX1537AETX+ -40C to +85C 36 Thin QFN 6mm x 6mm THIN QFN +Denotes lead-free package. 5mm x 5mm Dual Mode is a trademark of Maxim Integrated Products, Inc. Pin Configurations continued at end of data sheet. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim s website at www.maxim-ic.com. PGDLY SHDN PGOOD SKIP UVP DH5 DH3 BST5 BST3 LX5 LX3 IN OVP CSH5 CSH3 CSL5High-Efficiency, 5x Output, Main Power-Supply Controllers for Notebook Computers ABSOLUTE MAXIMUM RATINGS IN, SHDN, INA, LDOA to GND ...............................-0.3V to +30V LX5 to BST5..............................................................-6V to +0.3V DH5 to LX5 ..............................................-0.3V to (V + 0.3V) GND to PGND .......................................................-0.3V to +0.3V BST5 LDO5, LDO3, V to GND .......................................-0.3V to +6V LDO3, LDO5 Short Circuit to GND.............................Momentary CC REF Short Circuit to GND ...........................................Momentary ILIM3, ILIM5, PGDLY to GND...................................-0.3V to +6V INA Shunt Current.............................................................+15mA CSL3, CSH3, CSL5, CSH5 to GND ..........................-0.3V to +6V ON3, ON5, FB3, FB5 to GND ..................................-0.3V to +6V Continuous Power Dissipation (T = +70C) A 32-Pin TQFN (derate 21.3mW/C above +70C) .......1702mW SKIP, OVP, UVP to GND...........................................-0.3V to +6V PGOOD, FSEL, ADJA, ONA to GND........................-0.3V to +6V 36-Pin TQFN (derate 26.3mW/C above +70C) .......2105mW Operating Temperature Range ...........................-40C to +85C REF to GND................................................-0.3V to (V + 0.3V) CC Junction Temperature......................................................+150C DL3, DL5 to PGND..................................-0.3V to (V + 0.3V) LDO5 BST3, BST5 to PGND .............................................-0.3V to +36V Storage Temperature Range .............................-65C to +150C Lead Temperature (soldering, 10s) .................................+300C LX3 to BST3..............................................................-6V to +0.3V DH3 to LX3 ..............................................-0.3V to (V + 0.3V) BST3 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 (Circuit of Figure 1, V = 12V, both SMPS enabled, V = 5V, FSEL = REF, SKIP = GND, V = V , V = 15V, V = 12V, IN CC ILIM LDO5 INA LDOA I = I = I = no load, T = 0C to +85C, unless otherwise noted. Typical values are at T = +25C.) LDO5 LDO3 LDOA A A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS INPUT SUPPLIES (Note 1) LDO5 in regulation 6 26 V Input Voltage Range V V IN IN IN = LDO5, V < 4.43V 4.5 5.5 OUT5 V Operating Supply Current I LDO5 switched over to CSL5 15 35 A IN IN V = 6V to 26V, both SMPS off, IN V Standby Supply Current I 100 170 A IN IN(STBY) includes I SHDN V Shutdown Supply Current I V = 6V to 26V, SHDN = GND 5 17 A IN IN(SHDN) IN Both SMPS on, FB3 = FB5 = SKIP = GND, Quiescent Power Consumption P V = 3.5V, V = 5.3V, V = 15V, 3.5 4.5 mW Q CSL3 CSL5 INA I = 0, P + P + P + P LDOA IN CSL3 CSL5 INA Both SMPS on, FB3 = FB5 = GND, V Quiescent Supply Current I 1.1 2.1 mA CC CC V = 3.5V, V = 5.3V CSL3 CSL5 MAIN SMPS CONTROLLERS 3.3V Output Voltage in Fixed V V = 6V to 26V, SKIP = V (Note 2) 3.280 3.33 3.380 V OUT3 IN CC Mode 5V Output Voltage in Fixed Mode V V = 6V to 26V, SKIP = V (Note 2) 4.975 5.05 5.125 V OUT5 IN CC Feedback Voltage in Adjustable V = 6V to 26V, FB3 or FB5, IN V 0.990 1.005 1.020 V FB Mode duty factor = 20% to 80% (Note 2) Output-Voltage Adjust Range Either SMPS 1.0 5.5 V FB3, FB5 Dual-Mode Threshold 0.1 0.2 V Feedback Input Leakage Current V = V = 1.1V -0.1 +0.1 A FB3 FB5 Either SMPS, SKIP = V , CC DC Load Regulation -0.1 % I = 0 to full load LOAD 2 MAX1533A/MAX1537A