MAX870/MAX871 19-1240 Rev 1 2/04 Switched-Capacitor Voltage Inverters General Description Features The ultra-small MAX870/MAX871 monolithic, CMOS 5-Pin SOT23-5 Package charge-pump inverters accept input voltages ranging 99% Voltage Conversion Efficiency from +1.4V to +5.5V. The MAX870 operates at 125kHz, and the MAX871 operates at 500kHz. Their high efficien- Invert Input Supply Voltage cy (90%) and low operating current (0.7mA for the 0.7mA Quiescent Current (MAX870) MAX870) make these devices ideal for both battery-pow- ered and board-level voltage-conversion applications. +1.4V to +5.5V Input Voltage Range Oscillator control circuitry and four power MOSFET Require Only Two Capacitors switches are included on-chip. A typical MAX870/ MAX871 application is generating a -5V supply from a 25mA Output Current +5V logic supply to power analog circuitry. Both parts Shutdown Control come in a 5-pin SOT23-5 package and can deliver 25mA with a voltage drop of 500mV. For a similar device with logic-controlled shutdown, refer to the MAX1720/MAX1721. For applications Ordering Information requiring more power, the MAX860 delivers up to 50mA with a voltage drop of 600mV, in a space-saving MAX PIN- SOT package. PART TEMP RANGE PACKAGE TOP MARK MAX870EUK -40C to +85C 5 SOT23-5 ABZN Applications MAX871EUK -40C to +85C 5 SOT23-5 ABZO Local -5V Supply from 5V Logic Supply Small LCD Panels Cell Phones Medical Instruments Handy-Terminals, PDAs Battery-Operated Equipment Typical Operating Circuit Pin Configuration TOP VIEW INPUT 52 IN C1+ SUPPLY VOLTAGE MAX870 OUT 1 5 C1+ MAX871 MAX870 3 IN 2 C1- MAX871 NEGATIVE 1 OUT OUTPUT VOLTAGE C1- 3 GND 4 4 GND SOT23-5 NEGATIVE VOLTAGE CONVERTER 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.Switched-Capacitor Voltage Inverters ABSOLUTE MAXIMUM RATINGS IN to GND..............................................................+6.0V to -0.3V Continuous Power Dissipation (T = +70C) A OUT to GND ..........................................................-6.0V to +0.3V SOT23-5 (derate 7.1mW/C above +70C)...................571mW C1+ ..............................................................(V + 0.3V) to -0.3V Operating Temperature Range IN C1-............................................................(V - 0.3V) to +0.3V MAX870EUK/MAX871EUK ...............................-40C to +85C OUT OUT Output Current ...........................................................50mA Storage Temperature Range .............................-65C to +160C OUT Short Circuit to GND .............................................Indefinite 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 (V = +5V, C1 = C2 = 1F (MAX870), C1 = C2 = 0.33F (MAX871), T = 0C to +85C, unless otherwise noted. Typical values IN A are at T = +25C.) A PARAMETER CONDITIONS MIN TYP MAX UNITS MAX870 0.7 1.0 Supply Current T = +25C (Note 3) mA A MAX871 2.7 3.8 T = +25C 1.4 1.0 A Minimum Supply Voltage R = 10k V LOAD T = 0C to + 85C 1.5 A Maximum Supply Voltage R = 10k 5.5 V LOAD MAX870 81 125 169 Oscillator Frequency T = +25C kHz A MAX871 325 500 675 MAX870 90 R = 500k , LOAD Power Efficiency % T =+25C A MAX871 75 MAX870 98 99.3 Voltage Conversion Efficiency R = , T =+25C % LOAD A MAX871 96 99 C1 = C2 = 1F 20 50 MAX870 C1 = C2 = 0.47F 25 T = +25C C1 = C2 = 0.33F 20 50 A I = OUT Output Resistance (Note 1) 5mA MAX871 C1 = C2 = 0.22F 25 C1 = C2 = 0.1F 35 T = 0C to + 85C 65 A Note 1: Capacitor contribution is approximately 20% of the output impedance ESR + 1 / (pump frequency x capacitance) . ELECTRICAL CHARACTERISTICS (V = +5V, C1 = C2 = 1F (MAX870), C1 = C2 = 0.33F (MAX871), T = -40C to +85C, unless otherwise noted.) (Note 2) IN A PARAMETER CONDITIONS MIN TYP MAX UNITS MAX870 1.3 Supply Current (Note 3) mA MAX871 4.4 Minimum Supply-Voltage Range R = 10k 1.6 V LOAD Maximum Supply-Voltage Range R = 10k 5.5 V LOAD MAX870 56 194 Oscillator Frequency kHz MAX871 225 775 Output Resistance I = 5mA 65 OUT MAX870 97 Voltage Conversion Efficiency R = % LOAD MAX871 95 Note 2: All -40C to +85C specifications are guaranteed by design. Note 3: The MAX870/MAX871 may draw high supply current during startup, up to the minimum operating supply voltage. To guarantee proper startup, the input supply must be capable of delivering 90mA more than the maximum load current. 2 MAX870/MAX871