MAX1777/MAX1977/MAX1999 19-2187 Rev 1 9/04 High-Efficiency, Quad Output, Main Power- Supply Controllers for Notebook Computers General Description Features No Current-Sense Resistor Needed (MAX1999) The MAX1777/MAX1977/MAX1999 dual step-down, switch-mode power-supply (SMPS) controllers generate Accurate Current Sense with Current-Sense Resistor (MAX1777/MAX1977) logic-supply voltages in battery-powered systems. The MAX1777/MAX1977/MAX1999 include two pulse-width 1.5% Output Voltage Accuracy modulation (PWM) controllers, adjustable from 2V to 5.5V 3.3V and 5V 100mA Bootstrapped Linear or fixed at 5V and 3.3V. These devices feature two linear Regulators regulators providing 5V and 3.3V always-on outputs. Internal Soft-Start and Soft-Stop Output Each linear regulator provides up to 100mA output cur- Discharge rent with automatic linear regulator bootstrapping to the Quick-PWM with 100ns Load Step Response main SMPS outputs. The MAX1777/MAX1977/MAX1999 3.3V and 5V Fixed or Adjustable Outputs include on-board power-up sequencing, a power-good (Dual Mode) (PGOOD) output, digital soft-start, and internal soft-stop 4.5V to 24V Input Voltage Range output discharge that prevents negative voltages on shut- Ultrasonic Pulse-Skipping Mode (25kHz min) down. Power-Good (PGOOD) Signal Maxims proprietary Quick-PWM quick-response, con- Overvoltage Protection Enable/Disable stant on-time PWM control scheme operates without sense resistors and provides 100ns response to load Ordering Information transients while maintaining a relatively constant switch- 5V/3V ing frequency. The unique ultrasonic pulse-skipping PIN- PART TEMP RANGE SWITCHING mode maintains the switching frequency above 25kHz, PACKAGE FREQUENCY which eliminates noise in audio applications. Other fea- MAX1777EEI -40C to +85C 28 QSOP 200kH z/300kH z tures include pulse skipping, which maximizes efficiency in light-load applications, and fixed-frequency PWM MAX1777EEI+ -40C to +85C 28 QSOP 200kH z/300kH z mode, which reduces RF interference in sensitive appli- MAX1977EEI -40C to +85C 28 QSOP 400kH z/500kH z cations. MAX1977EEI+ -40C to +85C 28 QSOP 400kH z/500kH z The MAX1777 features a 200kHz/5V and 300kHz/3.3V 200kH z/300kH z or MAX1999EEI -40C to +85C 28 QSOP SMPS for highest efficiency, while the MAX1977 features 400kH z/500kH z a 400kHz/5V and 500kHz/3.3V SMPS for thin and light 200kH z/300kH z or applications. The MAX1999 provides a pin-selectable MAX1999EEI+ -40C to +85C 28 QSOP 400kH z/500kH z switching frequency, allowing either 200kHz/300kHz or +Denotes lead-free package. 400kHz/500kHz operation of the 5V/3.3V SMPSs, respec- tively. The MAX1777/MAX1977/MAX1999 are available in Pin Configurations 28-pin QSOP packages and operate over the extended temperature range (-40C to +85C). The MAX1777/ TOP VIEW MAX1977/MAX1999 are available in lead-free packages. N.C. 1 28 BST3 Applications PGOOD 2 27 LX3 ON3 3 26 DH3 Notebook and Subnotebook Computers ON5 4 25 LDO3 PDAs and Mobile Communication Devices ILIM3 5 24 DL3 MAX1999 3- and 4-Cell Li+ Battery-Powered Devices SHDN 6 23 GND FB3 7 22 OUT3 REF 8 21 OUT5 FB5 9 20 V+ PRO 10 19 DL5 ILIM5 11 18 LDO5 Quick-PWM and Dual Mode are trademarks of Maxim SKIP 12 17 V CC Integrated Products, Inc. TON 13 16 DH5 BST5 14 15 LX5 QSOP Pin Configurations continued at end of data sheet. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.High-Efficiency, Quad Output, Main Power- Supply Controllers for Notebook Computers ABSOLUTE MAXIMUM RATINGS V+, SHDN to GND..................................................-0.3V to +25V LDO3, LDO5, REF Short Circuit to GND ....................Momentary LDO3 Current (Internal Regulator) Continuous ..............+100mA BST to GND ..........................................................-0.3V to +30V LDO3 Current (Switched Over to OUT3) Continuous.....+200mA LX to BST ..............................................................-6V to +0.3V CS to GND (MAX1777/MAX1977 only)......................-2V to +6V LDO5 Current (Internal Regulator) Continuous ..............+100mA LDO5 Current (Switched Over to OUT5) Continuous.....+200mA V , LDO5, LDO3, OUT3, OUT5, ON3, ON5, REF, CC FB3, FB5, SKIP, PRO, PGOOD to GND ...............-0.3V to +6V Continuous Power Dissipation 28-Pin QSOP (derate 10.8mW/C above +70C).........860mW DH3 to LX3 ..............................................-0.3V to (V + 0.3V) BST3 Operating Temperature Range ...........................-40C to +85C DH5 to LX5 ..............................................-0.3V to (V + 0.3V) BST5 ILIM3, ILIM5 to GND...................................-0.3V to (V + 0.3V) Junction Temperature......................................................+150C CC Storage Temperature Range .............................-65C to +150C DL3, DL5 to GND....................................-0.3V to (V + 0.3V) LDO5 TON to GND (MAX1999 only)...................................-0.3V to +6V Lead Temperature (soldering, 10s) .................................+300C 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 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF, V+ = 12V, ON3 = ON5 = V , V = 5V, CC SHDN T = 0C to +85C, unless otherwise noted. Typical values are at T = +25C.) A A PARAMETER CONDITIONS MIN TYP MAX UNITS MAIN SMPS CONTROLLERS LDO5 in regulation 6 24 V+ Input Voltage Range V V+ = LDO5, V < 4.43V 4.5 5.5 OUT5 3.3V Output Voltage in V+ = 6V to 24V, FB3 = GND, V = 5V 3.285 3.330 3.375 V SKIP Fixed Mode V+ = 6V to 24V, FB5 = GND, V = 5V, SKIP MAX1777/MAX1999 (TON = V ) CC 5V Output Voltage in Fixed Mode 4.975 5.050 5.125 V V+ = 7V to 24V, FB5 = GND, V = 5V, SKIP MAX1977/MAX1999 (TON = GND) Output Voltage in V+ = 6V to 24V, either SMPS 1.975 2.00 2.025 V Adjustable Mode Output Voltage Adjust Range Either SMPS 2.0 5.5 V FB3, FB5 Adjustable-Mode Dual-mode comparator 0.1 0.2 V Threshold Voltage Either SMPS, V = 5V, 0 to 5A -0.1 SKIP DC Load Regulation Either SMPS, SKIP = GND, 0 to 5A -1.5 % Either SMPS, V = 2V, 0 to 5A -1.7 SKIP Line Regulation Either SMPS, 6V < V+ < 24V 0.005 %/V Current-Limit Threshold ILIM = V , GND - CS (MAX1777/MAX1977), CC 93 100 107 mV (Positive, Default) GND - LX (MAX1999) V = 0.5V 40 50 60 ILIM GND - CS Current-Limit Threshold (MAX1777/MAX1977), V = 1V 93 100 107 mV ILIM (Positive, Adjustable) GND - LX (MAX1999) V = 2V 185 200 215 ILIM SKIP = GND, ILIM = V , GND - CS CC Zero-Current Threshold 3mV (MAX1777/MAX1977), GND - LX (MAX1999) Current-Limit Threshold SKIP = ILIM = V , GND - CS (MAX1777/MAX1977), CC -120 mV (Negative, Default) GND - LX (MAX1999) Soft-Start Ramp Time Zero to full limit 1.7 ms 2 MAX1777/MAX1977/MAX1999