MAX1675EUA

EVALUATION KIT AVAILABLE MAX1674/MAX1675/MAX1676 High-Efficiency, Low-Supply-Current, Compact, Step-Up DC-DC Converters LE AVAILAB General Description The MAX1674/MAX1675/MAX1676 compact, high-efficiency, step-up DC-DC converters fit in small µMAX packages. They feature a built-in synchronous rectifier, which improves efficiency and reduces size and cost by eliminating the need for an external Schottky diode. Quiescent supply current is only 16µA. The input voltage ranges from 0.7V to VOUT, where VOUT can be set from 2V to 5.5V. Start-up is guaranteed from 1.1V inputs. The MAX1674/MAX1675/ MAX1676 have a preset, pin-selectable output for 5V or 3.3V. The outputs can also be adjusted to other voltages using two external resistors. All three devices have a 0.3Ω N-channel MOSFET power switch. The MAX1674 has a 1A current limit. The MAX1675 has a 0.5A current limit, which permits the use of a smaller inductor. The MAX1676 comes in a 10-pin µMAX package and features an adjustable current limit and circuitry to reduce inductor ringing. ________________________Applications Pagers Wireless Phones Medical Devices Hand-Held Computers ____________________________Features ♦ 94% Efficient at 200mA Output Current ♦ 16µA Quiescent Supply Current ♦ Internal Synchronous Rectifier (no external diode) ♦ 0.1µA Logic-Controlled Shutdown ♦ LBI/LBO Low-Battery Detector ♦ Selectable Current Limit for Reduced Ripple ♦ Low-Noise, Anti-Ringing Feature (MAX1676) ♦ 8-Pin and 10-Pin µMAX Packages ♦ Preassembled Evaluation Kit (MAX1676EVKIT) _______________Ordering Information PART TEMP. RANGE PIN-PACKAGE MAX1674EUA MAX1675EUA MAX1676EUB -40°C to +85°C -40°C to +85°C -40°C to +85°C 8 µMAX 8 µMAX 10 µMAX PDAs RF Tags Pin Configurations 1 to 3-Cell Hand-Held Devices Functional Diagrams Typical Operating Circuit TOP VIEW FB 1 INPUT 0.7V TO VOUT LBI 2 LBO 3 MAX1674 MAX1675 REF 4 ON SHDN OFF LX MAX1674 OUT MAX1675 OUTPUT 3.3V, 5V, OR ADJ (2V TO 5.5V) UP TO 300mA FB 1 LBI REF 0.1µF LBO FB LOW-BATTERY DETECT OUT GND Pin Configurations appear at end of data sheet. Functional Diagrams continued at end of data sheet. UCSP is a trademark of Maxim Integrated Products, Inc. OUT 7 LX 6 GND 5 SHDN µMAX 10 OUT LBI 2 LOW-BATTERY DETECT IN 8 LBO 3 MAX1676 9 LX 8 GND CLSEL 4 7 BATT REF 5 6 SHDN µMAX For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com. 19-1360; Rev 3; 3/00 MAX1674/MAX1675/MAX1676 High-Efficiency, Low-Supply-Current, Compact, Step-Up DC-DC Converters ABSOLUTE MAXIMUM RATINGS Supply Voltage (OUT to GND) ..............................-0.3V to +6.0V Switch Voltage (LX to GND) .....................-0.3V to (VOUT + 0.3V) Battery Voltage (BATT to GND).............................-0.3V to +6.0V SHDN, LBO to GND ..............................................-0.3V to +6.0V LBI, REF, FB, CLSEL to GND ...................-0.3V to (VOUT + 0.3V) Switch Current (LX) ...............................................-1.5A to +1.5A Output Current (OUT) ...........................................-1.5A to +1.5A Continuous Power Dissipation (TA = +70°C) 8-Pin µMAX (derate 4.1mW/°C above +70°C) .............330mW 10-Pin µMAX (derate 5.6mW/°C above +70°C) ...........444mW Operating Temperature Range ...........................-40°C to +85°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +165°C Lead Temperature (soldering, 10s) .................................+300°C 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 (VBATT = 2V, FB = OUT (VOUT = 3.3V), RL = ˙∞, TA = 0°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) PARAMETER SYMBOL CONDITIONS MIN Operating Voltage VIN Start-Up Voltage 1.1 TA = +25°C VOUT 3.17 3.30 3.43 4.80 5 5.20 IOUT VREF 300 420 MAX1675, MAX1676 (CLSEL = GND) 150 220 MAX1674, MAX1676 (CLSEL = OUT) 180 285 MAX1675, MAX1676 (CLSEL = GND) 90 130 IREF = 0 1.274 1.30 1.326 0.024 TEMPCO V V V mV/°C Reference Voltage Load Regulation VREF_LOAD IREF = 0 to 100µA 3 15 mV Reference Voltage Line Regulation VREF_LINE VOUT = 2V to 5.5V 0.08 2.5 mV/V 1.30 1.326 V 0.3 0.6 Ω 1.274 FB, LBI Input Threshold Internal NFET, PFET On-Resistance LX Switch Current Limit (NFET) LX Leakage Current 2 V mA FB = GND (VOUT = 5V) Reference Voltage Tempco 5.5 MAX1674, MAX1676 (CLSEL = OUT) V mV/°C FB = GND FB = OUT (VOUT = 3.3V) Reference Voltage 1.1 FB = OUT 2 UNITS V -2 Output Voltage Range Steady-State Output Current (Note 2) MAX 5.5 0.9 TA = +25°C, RL = 3kΩ (Note 1) Start-Up Voltage Tempco Output Voltage TYP 0.7 Minimum Input Voltage RDS(ON) ILIM ILEAK ILX = 100mA MAX1674, MAX1676 (CLSEL = OUT) 0.80 1 1.20 MAX1675, MAX1676 (CLSEL = GND) 0.4 0.5 0.65 0.05 1 VLX = 0, 5.5V; VOUT = 5.5V A µA Maxim Integrated MAX1674/MAX1675/MAX1676 High-Efficiency, Low-Supply-Current, Compact, Step-Up DC-DC Converters ELECTRICAL CHARACTERISTICS (continued) (VBATT = 2V, FB = OUT (VOUT = 3.3V), RL = ˙∞, TA = 0°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) PARAMETER Operating Current into OUT (Note 3) Shutdown Current into OUT SYMBOL Efficiency CONDITIONS MIN TYP MAX UNITS VFB = 1.4V, VOUT = 3.3V 16 35 µA SHDN = GND 0.1 1 µA VOUT = 3.3V, ILOAD = 200mA 90 VOUT = 2V, ILOAD = 1mA 85 LX Switch On-Time tON VFB = 1V, VOUT = 3.3V 3 LX Switch Off-Time tOFF VFB = 1V, VOUT = 3.3V 0.8 FB Input Current IFB VFB = 1.4V ILBI VLBI = 1.4V % 4 7 µs 1 1.2 µs 0.03 50 nA 1 50 nA CLSEL Input Current ICLSEL MAX1676, CLSEL = OUT 1.4 3 µA SHDN Input Current I SHDN V SHDN = 0 or VOUT 0.07 50 nA VLBI = 0, ISINK = 1mA 0.2 0.4 V V LBO = 5.5V, VLBI = 5.5V 0.07 1 µA 150 Ω LBI Input Current LBO Low Output Voltage LBO Off Leakage Current I LBO Damping Switch Resistance SHDN Input Voltage CLSEL Input Voltage MAX1676, VBATT = 2V 88 VIL 0.2VOUT VIH 0.8VOUT VIL 0.2VOUT VIH 0.8VOUT V V ELECTRICAL CHARACTERISTICS (VBATT = 2V, FB = OUT, RL = ∞, TA = -40°C to +85°C, unless otherwise noted.) (Note 4) PARAMETER Output Voltage SYMBOL VOUT MIN MAX FB = OUT CONDITIONS 3.13 3.47 FB = GND 4.75 5.25 Output Voltage Range Reference Voltage VREF IREF = 0 FB, LBI Thresholds Internal NFET, PFET On-Resistance 2.20 5.5 V 1.3325 V 1.2675 1.3325 V 0.6 Ω 40 µA VFB = 1.4V, VOUT = 3.3V SHDN = GND Shutdown Current into OUT V 1.2675 RDS(ON) Operating Current into OUT (Note 3) UNITS 1 µA LX Switch On-Time tON VFB = 1V, VOUT = 3.3V 2.7 7.0 µs LX Switch Off-Time tOFF VFB = 1V, VOUT = 3.3V 0.75 1.25 µs MAX1674, MAX1676 (CLSEL = OUT) 0.75 1.25 MAX1675, MAX1676 (CLSEL = GND) 0.36 0.69 LX Switch Current Limit (NFET) Maxim Integrated ILIM A 3 MAX1674/MAX1675/MAX1676 High-Efficiency, Low-Supply-Current, Compact, Step-Up DC-DC Converters ELECTRICAL CHARACTERISTICS (continued) (VBATT = 2V, FB = OUT, RL = ∞, TA = -40°C to +85°C, unless otherwise noted.) (Note 4) MAX UNITS CLSEL Input Current PARAMETER SYMBOL ICLSEL MAX1676, CLSEL = OUT 3 µA SHDN Input Current I SHDN VSHDN = 0 or VOUT 75 nA V LBO = 5.5V, VLBI = 5.5V 1 µA LBO Off Leakage Current I LBO CONDITIONS MIN Note 1: Start-up voltage operation is guaranteed with the addition of a Schottky MBR0520 external diode between the input and output. Note 2: Steady-state output current indicates that the device maintains output voltage regulation under load. See Figures 5 and 6. Note 3: Device is bootstrapped (power to the IC comes from OUT). This correlates directly with the actual battery supply. Note 4: Specifications to -40°C are guaranteed by design, not production tested. Typical Operating Characteristics (L = 22µH, CIN = 47µF, COUT = 47µF 0.1µF, CREF = 0.1µF, TA = +25°C, unless otherwise noted.) EFFICIENCY vs. LOAD CURRENT 80 VIN = 2.4V 70 EFFICIENCY (%) EFFICIENCY (%) 90 VIN = 1.2V 60 50 40 50 40 20 20 VOUT = 5V ILIMIT = 500mA 10 0 0.01 0.1 1 10 100 VIN = 3.6V VIN = 1.2V 60 30 0 0.01 0.1 1 10 100 VOUT = 3.3V ILIMIT = 500mA 0 1000 0.01 0.1 VIN = 2.4V VIN = 1.2V 60 50 40 30 20 VOUT = 3.3V ILIMIT = 1A 10 0 1 10 LOAD CURRENT (mA) 100 1 10 100 1000 LOAD CURRENT (mA) 1000 MAX1674 toc05 1.300 REFERENCE OUTPUT VOLTAGE (V) MAX1674 toc04 80 EFFICIENCY (%) 40 REFERENCE OUTPUT VOLTAGE vs. TEMPERATURE 90 4 50 LOAD CURRENT (mA) 100 0.1 60 10 EFFICIENCY vs. LOAD CURRENT 0.01 VIN = 1.2V 20 VOUT = 5V ILIMIT = 1A LOAD CURRENT (mA) 70 VIN = 2.4V 70 30 10 1000 80 VIN = 2.4V 70 30 90 EFFICIENCY (%) VIN = 3.6V 80 100 MAX1674 toc02 MAX1674 toc01 90 EFFICIENCY vs. LOAD CURRENT 100 MAX1674 toc03 EFFICIENCY vs. LOAD CURRENT 100 1.298 IREF = 0 1.296 1.294 IREF = 100µA 1.292 1.290 -40 -20 0 20 40 60 80 100 TEMPERATURE (°C) Maxim Integrated MAX1674/MAX1675/MAX1676 High-Efficiency, Low-Supply-Current, Compact, Step-Up DC-DC Converters Typical Operating Characteristics (continued) (L = 22µH, CIN = 47µF, COUT = 47µF 0.1µF, CREF = 0.1µF, TA = +25°C, unless otherwise noted.) NO-LOAD BATTERY CURRENT vs. INPUT BATTERY VOLTAGE 100 80 ILIMIT = 0.5A, 5.0V 60 ILIMIT = 0.5A, 3.3V 20 ILIMIT = 1A, 3.3V 0 1.0 0.8 0.6 WITH 1N5817 -1.0 0.01 0.1 1 100 MAXIMUM OUTPUT CURRENT vs. INPUT VOLTAGE (VOUT = 3.3V) 0.6 0.4 0.2 MAX1674toc11 1A CURRENT LIMIT 600 500 400 300 200 0.5A CURRENT LIMIT 800 MAXIMUM OUTPUT CURRENT (mA) 0.8 800 700 100 0 1.0 1.5 2.0 MAX1674 TOC13 2.5 3.0 3.5 4.0 0.5A CURRENT LIMIT 100 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 1.2 MAX1674toc13.5 P-CHANNEL 0.35 MAX1674, MAX1676 (CLSEL = OUT) 1.0 0.8 0.30 ILIM (A) RESISTANCE (Ω) 200 LX CURRENT LIMIT vs. OUTPUT VOLTAGE N-CHANNEL 0.25 0.20 0.6 0.4 0.15 MAX1675, MAX1676 (CLSEL = GND) 0.10 0.2 0.05 0 -60 -40 -20 0 20 40 TEMPERATURE (°C) Maxim Integrated 300 4.5 0 1µs/div 400 SWITCH RESISTANCE vs. TEMPERATURE 0.40 VOUT AC COUPLED 100mV/div 1A CURRENT LIMIT 500 INPUT VOLTAGE (V) 0.45 VLX 5V/div ILX 0.5A/div 600 INPUT VOLTAGE (V) SUPPLY VOLTAGE (V) HEAVY-LOAD SWITCHING WAVEFORMS 700 0 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 SUPPLY VOLTAGE (V) 900 MAXIMUM OUTPUT CURRENT (mA) MAX1674TOC10 SHUTDOWN THRESHOLD (V) 1 10 LOAD CURRENT (mA) MAXIMUM OUTPUT CURRENT vs. INPUT VOLTAGE (VOUT = 5V) 1.0 VIN = 2.4V VOUT = 5.0V -0.4 -0.8 SHUTDOWN THRESHOLD vs. SUPPLY VOLTAGE 0 0 -0.2 -0.6 INPUT BATTERY VOLTAGE (V) 1.2 0.2 0.2 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 1.4 0.4 0.4 0 0 MAX167toc09 MAX1674toc08 WITHOUT DIODE 0.6 MAX1674toc12 40 1.4 1.2 0.8 MAX1674toc14 ILIMIT = 1A, 5.0V 1.0 SHUTDOWN CURRENT (µA) 120 1.6 START-UP VOLTAGE (V) 140 INPUT BATTERY CURRENT (µA) 1.8 MAX1674toc07 160 SHUTDOWN CURRENT vs. SUPPLY VOLTAGE START-UP VOLTAGE vs. LOAD CURRENT 60 80 100 2.0 2.5 3.0 3.5 4.0 4.5 5.0 OUTPUT VOLTAGE (V) 5 MAX1674/MAX1675/MAX1676 High-Efficiency, Low-Supply-Current, Compact, Step-Up DC-DC Converters Typical Operating Characteristics (continued) (L = 22µH, CIN = 47µF, COUT = 47µF 0.1µF, CREF = 0.1µF, TA = +25°C, unless otherwise noted.) LOAD-TRANSIENT RESPONSE LINE-TRANSIENT RESPONSE MAX1674 TOC17 VIN = 2.4V VOUT = 3.3V VIN 2V TO 3V 1V/div VOUT 2V/div IOUT 200mA/div VSHDN 2V/div VOUT 50mV/div AC COUPLED VOUT AC COUPLED 100mV/div ILOAD 100mA EXITING SHUTDOWN MAX1674 TOC16 MAX1674 TOC15 5µs/div 10µs/div 500µs/div Pin Description PIN NAME FUNCTION MAX1674 MAX1675 MAX1676 1 1 FB Dual-Mode™ Feedback Input. Connect to GND for +5.0V output. Connect to OUT for +3.3V output. Use a resistor network to set the output voltage from +2.0V to +5.5V. 2 2 LBI Low-Battery Comparator Input. Internally set to trip at +1.30V. 3 3 LBO Open-Drain Low-Battery Comparator Output. Connect LBO to OUT through a 100kΩ resistor. Output is low when VLBI is 80% of VOUT) for operating mode. Drive low (