Page No. : 1/12 RS7100 Low Power 300mA CMOS LDO General Description The RS7100 is a low‐dropout linear regulator that operations in the input voltage range from +2.5V to +9.0V and delivers 300mA output current. The high‐accuracy output voltage is preset at an internally trimmed voltage 2.5V or 3.3V. Other output voltages can be mask‐optioned from 1.5V to 5.0V with 100mV increment. The RS7100 consists of a 1.25V bandgap reference, an error amplifier, and a P‐channel pass transistor. Other features include short‐circuit protection and thermal shutdown protection. The RS7100 devices are available in SOT‐23 and SOT‐89 packages. Features Applications ● Operating Voltages Range: +2.5V to +9.0V ● Output Voltages Range: +1.5V to +5.0V with 100mV Increment ● Maximum Output Current: 300mA ● Low Dropout: 120mV@100mA (VOUT≥2.0V) ● ±2% Output Voltage Accuracy ● High Ripple Rejection: 70dB ● Output Current Limit Protection (600mA) ● Short Circuit Protection (300mA) ● Thermal Overload Shutdown Protection ● Low ESR Capacitor Compatible ● RoHS Compliant and 100% Lead (Pb)‐Free and Green (Halogen Free with Commercial Standard) ● ● ● ● ● ● Battery‐powered equipment Voltage regulator for microprocessor Voltage regulator for LAN cards Wireless Communication equipment Audio/Video equipment Post Regulator for Switching Power Application Circuits This integrated circuit can be damaged by ESD. Orister Corporation recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet its published specifications. DS‐RS7100‐14 April, 2010 www.Orister.com Page No. : 2/12 Pin Assignments SOT‐23 SOT‐89 PACKAGE SOT‐23 PIN 1 2 3 SYMBOL GND VOUT VIN DESCRIPTION Ground Pin Regulator Output Pin Regulator Input Pin PIN 1 2 3 SYMBOL GND VOUT VIN DESCRIPTION Ground Pin Regulator Output Pin Regulator Input Pin PACKAGE SOT‐89 Ordering Information DEVICE RS7100‐XX Y Z DEVICE CODE XX is nominal output voltage (for example, 15 = 1.5V, 33 = 3.3V, 285 = 2.85V). Y is package designator : N: SOT‐23 M: SOT‐89 Z is Lead Free designator : P: Commercial Standard, Lead (Pb) Free and Phosphorous (P) Free Package G: Green (Halogen Free with Commercial Standard) Block Diagram DS‐RS7100‐14 April, 2010 www.Orister.com Page No. : 3/12 Absolute Maximum Ratings Parameter Input Voltage VIN to GND Output Current Limit, I(LIMIT) Junction Temperature Symbol VIN ILIMIT TJ Ratings Units 10 V 600 mA o +155 C SOT‐23 280 o Thermal Resistance C/W θJA SOT‐89 180 SOT‐23 350 Power Dissipation PD mW SOT‐89 550 o Operating Ambient Temperature TOPR ‐40 ~ +85 C o Storage Temperature TSTG ‐55~+150 C o Lead Temperature (soldering, 10sec) ‐ +260 C NOTE: Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and function operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not implied. Exposure to absolute‐maximum–rated conditions for extended periods may affect device reliability. Electrical Characteristics (TA=25°C, unless otherwise specified) Symbol VIN Parameter Input Voltage VOUT Output Voltage ΔVOUT Output Voltage Accuracy IMAX ILIMIT ISC IQ Output Current Current Limit Short Circuit Current Ground Pin Current VDROP Dropout Voltage ΔVLINE ΔVLOAD eN PSRR TSD THYS Line Regulation Load Regulation Output Noise Ripple Rejection Thermal Shutdown Temperature Thermal Shutdown Hysteresis Conditions ‐ VIN=VOUT+0.48V, IOUT=1mA, VOUT≤7.0V VIN=VOUT+0.48V, IOUT=1mA, 7.0V＜VIN≤9.0V VIN＞VOUT +0.48V, VIN≤7.0V VIN＞VOUT +0.48V, 7.0V<VIN≤9.0V ‐ ‐ VOUT=0V, VIN=5V ILOAD=0mA to 300mA, VIN=5.0V IOUT=100mA IOUT=300mA VOUT+0.48V<VIN<9.0V, ILOAD=1mA IOUT=0mA to 300mA F=1Hz to 10KHz, COUT=1uF F=1KHz, COUT=1uF ‐ ‐ Min. 2.5 Typ. ‐ Max. 9.0 Unit V ‐2% VOUT +2% V ‐2% VOUT +2% V 300 ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ 0.6 300 30 120 400 0.2 0.01 70 70 160 10 ‐ ‐ 350 50 145 480 0.3 0.02 ‐ ‐ ‐ ‐ mA A mA uA mV %/V %/mA uV(rms) dB o C o C DS‐RS7100‐14 April, 2010 www.Orister.com Page No. : 4/12 Typical Operating Characteristics (CIN=1μF, COUT=3.3μF, TA=+25 oC, unless otherwise noted.) DS‐RS7100‐14 April, 2010 www.Orister.com Page No. : 5/12 DS‐RS7100‐14 April, 2010 www.Orister.com Page No. : 6/12 DS‐RS7100‐14 April, 2010 www.Orister.com Page No. : 7/12 Detail Description The RS7100 is a low‐dropout linear regulator. The device provides preset 2.5V and 3.3V output voltages for output current up to 300mA. Other mask options for special output voltages from 1.5V to 5.0V with 100mV increment are also available. As illustrated in function block diagram, it consists of a 1.25V reference, error amplifier, a P‐channel pass transistor, and an internal feedback voltage divider. The 1.25V bandgap reference is connected to the error amplifier, which compares this reference with the feedback voltage and amplifies the voltage difference. If the feedback voltage is lower than the reference voltage, the pass‐transistor gate is pulled lower, which allows more current to pass to the output pin and increases the output voltage. If the feedback voltage is too high, the pass‐transistor gate is pulled up to decrease the output voltage. The output voltage is feedback through an internal resistive divider connected to VOUT pin. Additional blocks include with output current limiter and shutdown logic. Internal P‐channel Pass Transistor The RS7100 features a P‐channel MOSFET pass transistor. Unlike similar designs using PNP pass transistors, P‐channel MOSFETs require no base drive, which reduces quiescent current. PNP–based regulators also waste considerable current in dropout conditions when the pass transistor saturates, and use high base‐drive currents under large loads. The RS7100 does not suffer from these problems and consumes only 65μA (Typical) of ground pin current under heavy loads as well as in dropout conditions. Output Voltage Selection The RS7100 output voltage is preset at an internally trimmed voltage 2.5V or 3.3V or can be mask optioned from 1.5V to 5.0V with 100mV increment The first two digits of part number suffix identify the output voltage (see Ordering Information). For example, RS7100‐33 has a preset 3.3V output voltage. Current Limit The RS7100 also includes a fold back current limiter. It monitors and controls the pass‐transistor’s gate voltage, estimates the output current, and limits the output current within 600mA. Thermal Overload Protection Thermal overload protection limits total power dissipation in the RS7100. When the junction temperature exceeds TJ=+155°C, a thermal sensor turns off the pass transistor, allowing the IC to cool down. The thermal sensor turns the pass transistor active again after the junction temperature cools down by 20°C resulting in a pulsed output during continuous thermal overload conditions. Thermal overload protection is designed to protect the RS7100 in the event of fault conditions. For continuous operation, the maximum operating junction temperature rating of TJ=+125°C should not be exceeded. Operating Region and Power Dissipation Maximum power dissipation of the RS7100 depends on the thermal resistance of the case and circuit board, the temperature difference between the die junction and ambient air, and the rate of airflow. The power dissipation across the devices is P = IOUT x (VIN‐VOUT). The resulting maximum power dissipation is: (TJ − TA) (TJ − TA) = PMAX = θJC + θCA θJA Where (TJ‐TA) is the temperature difference between the RS7100 die junction and the surrounding air, θJC is the thermal resistance of the package chosen, and θCA is the thermal resistance through the printed circuit board, copper traces and other materials to the surrounding air. For better heat‐sinking, the copper area should be equally shared between the VIN, VOUT, and GND pins. If the RS7100 uses a SOT‐89 package and this package is mounted on a double sided printed circuit board with two square inches of copper allocated for “heat spreading”, the resulting θJA is 180°C/W. DS‐RS7100‐14 April, 2010 www.Orister.com Page No. : 8/12 Based on a maximum operating junction temperature 125°C with an ambient of 25°C, the maximum power dissipation will be: (TJ − TA) (125 − 25) PMAX = = = 0.555W θJC + θCA 180 Thermal characteristics were measured using a double‐side board with 1”x 2” square inches of copper area connected to the GND pin for “heat spreading”. Dropout Voltage A regulator’s minimum input‐output voltage differential, or dropout voltage, determines the lowest usable supply voltage. In battery‐powered systems, this will determine the useful end‐of‐life battery voltage. The RS7100 uses a P‐channel MOSFET pass transistor, its dropout voltage is a function of drain‐to‐source on‐resistance (RDS(ON)) multiplied by the load current. VDROPOUT = VIN − VOUT = RDS(ON) × IOUT DS‐RS7100‐14 April, 2010 www.Orister.com Page No. : 9/12 SOT‐23 Dimension NOTES: A. All linear dimensions are in millimeters. B. This drawing is subject to change without notice. C. Body dimensions do not include mold flash or protrusion. Mold flash and protrusion shall not exceed 0.15 per side. DS‐RS7100‐14 April, 2010 www.Orister.com Page No. : 10/12 SOT‐89 Dimension NOTES: A. All linear dimensions are in millimeters. B. This drawing is subject to change without notice. C. The center lead is in electrical contact with the tab. D. Body dimensions do not include mold flash or protrusion. Mold flash and protrusion shall not exceed 0.15 per side. E. Thermal pad contour optional within these dimensions. F. Falls within JEDEC TO‐243 variation AA, except minimum lead length, pin 2 minimum lead width, minimum tab width. DS‐RS7100‐14 April, 2010 www.Orister.com Page No. : 11/12 Soldering Methods for Orister’s Products 1. Storage environment: Temperature=10oC~35oC Humidity=65%±15% 2. Reflow soldering of surface‐mount devices Figure 1: Temperature profile tP Critical Zone TL to TP TP Ramp-up TL tL Temperature Tsmax Tsmin tS Preheat 25 Ramp-down t 25oC to Peak Time Profile Feature Average ramp‐up rate (TL to TP) Sn‐Pb Eutectic Assembly o <3 C/sec Preheat Pb‐Free Assembly <3oC/sec ‐ Temperature Min (Tsmin) 100oC 150oC ‐ Temperature Max (Tsmax) 150oC 200oC 60~120 sec 60~180 sec ‐ Time (min to max) (ts) Tsmax to TL ‐ Ramp‐up Rate o <3 C/sec <3 C/sec Time maintained above: ‐ Temperature (TL) ‐ Time (tL) o 217oC 183 C 60~150 sec Peak Temperature (TP) Time within 5oC of actual Peak Temperature (tP) Ramp‐down Rate Time 25oC to Peak Temperature o o o 60~150 sec 240 C +0/‐5 C 260oC +0/‐5oC 10~30 sec 20~40 sec <6oC/sec <6oC/sec <6 minutes <8 minutes Peak temperature Dipping time 3. Flow (wave) soldering (solder dipping) Products Pb devices. Pb‐Free devices. o o 245 C ±5 C o o 260 C +0/‐5 C 5sec ±1sec 5sec ±1sec DS‐RS7100‐14 April, 2010 www.Orister.com Page No. : 12/12 Important Notice: © Orister Corporation Orister cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an Orister product. No circuit patent licenses, copyrights, mask work rights, or other intellectual property rights are implied. Orister reserves the right to make changes to their products or specifications or to discontinue any product or service without notice. Except as provided in Orister’s terms and conditions of sale, Orister assumes no liability whatsoever, and Orister disclaims any express or implied warranty relating to the sale and/or use of Orister products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right. In order to minimize risks associated with the customer’s applications, adequate design and operating safeguards must be provided by the customer to minimize inherent or procedural hazards. Testing and other quality control techniques are utilized to the extent Orister deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily performed. Orister and the Orister logo are trademarks of Orister Corporation. All other brand and product names appearing in this document are registered trademarks or trademarks of their respective holders. DS‐RS7100‐14 April, 2010 www.Orister.com