19-0654; Rev 0; 11/06 28V, 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output Features +5V to +28V Wide Operating Input Voltage Range The MAX5091 high-voltage linear regulator is designed to operate from a +5V to +28V input voltage, and withstands up to 40V transients. The device consumes only 45A of quiescent current at 100A output current. The MAX5091 delivers up to 100mA of output current with low 50mV maximum dropout voltage. The MAX5091 provides an active-low open-drain microprocessor RESET output. The reset timeout period is programmable and can be set with an external capacitor. The MAX5091 includes an uncommitted comparator for input voltage monitoring/power-fail indication. The device is available with a fixed +5V (MAX5091A) or +3.3V (MAX5091B) output. The MAX5091 is short-circuit protected and includes thermal shutdown. The MAX5091 operates over the -40C to +125C automotive temperature range and is available in 8-pin, thermally enhanced TDFN and SO-EP packages. Withstands 40V Input Voltage Transients Guaranteed 100mA Output Current 45A Typical Quiescent Current at 100A Output Current Preset +5V (MAX5091A) or +3.3V (MAX5091B) Output Voltage Stable with Only 10F Output Capacitance RESET Output with Adjustable Timeout Period Uncommitted Comparator for Voltage Monitoring/Power-Fail Indication Output Overload and Short-Circuit Protection Thermal Shutdown Available in 8-Pin TDFN (1.95W at TA = +70C) and 8-Pin SO (1.5W at TA = +70C) Applications Automotive Home Security/Safety Industrial Telecom/Networking Operates Over -40C to +125C Automotive Temperature Range Ordering Information PINPACKAGE PART PRESET VOUT (V) PKG CODE TOP MARK MAX5091AATA+T 8 TDFN-8 5 T833-2 +APB MAX5091AASA+ 8 SO-EP* 5 S8E-14 -- +APC -- MAX5091BATA+T 8 TDFN-8 3.3 T833-2 MAX5091BASA+ 8 SO-EP* 3.3 S8E-14 Note: All devices specified for -40C to +125C operating temperature range. +Denotes lead-free package. *EP = Exposed paddle. Pin Configurations Typical Application Circuit +5V TO +28V VIN RH 288k TOP VIEW +5V (MAX5091A)/ +3.3V (MAX5091B) 100mA CIN 10F VS VOUT SO RES GND 8 7 6 5 VOUT COUT 10F RRES 10k MAX5091 ON MAX5091 EN OFF SI C RESET RES RL 100k RSO 10k CCT 0.1F SO CT GND EXPOSED PADDLE + POWERFAIL 1 2 3 4 VS SI EN CT TDFN (3mm x 3mm) Pin Configurations continued at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com. 1 MAX5091 General Description MAX5091 28V, 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output ABSOLUTE MAXIMUM RATINGS VS to GND ..............................................................-0.3V to +28V VS to GND (t 1s) ..................................................-0.3V to +40V VOUT to GND ..........................................................-0.3V to +20V VS to OUT ...............................................................-0.3V to +28V RES, SO to GND.....................................................-0.3V to +20V RES, SO Output Sink Current................................................5mA VOUT Short Circuit (VS 16V)............ ......................Continuous EN, SI to GND.........................................................-0.3V to +12V CT to GND.............................-0.3V to the lower of VOUT or +12V Continuous Power Dissipation (TA = +70C) 8-Pin SO-EP (derate 19.2mW/C above +70C) .........1538mW* Thermal Resistance (JA)................................................52C/W Thermal Resistance (JC)..................................................6C/W 8-Pin TDFN-EP (derate 24.4mW/C above +70C).....1951mW** Thermal Resistance (JA)................................................41C/W Thermal Resistance (JC)...............................................8.3C/W Operating Junction Temperature Range ...........-40C to +125C Maximum Junction Temperature .....................................+150C Storage Temperature Range .............................-60C to +150C Lead Temperature (soldering, 10s) .................................+300C *As per JEDEC51 Standard (single-layer board). **As per JEDEC51 Standard (multilayer board). 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 (MAX5091A) (VS = +14V, VOUT = 5V, EN unconnected, TA = TJ = -40C to +125C, CIN = 10F, COUT = 10F, unless otherwise noted. Typical specifications are at TA = +25C.) (Note 1) PARAMETER Output Voltage Dropout Voltage SYMBOL VOUT VDP MIN TYP MAX TA = +25C, IOUT = 1mA CONDITIONS 4.95 5 5.05 5.6V VS 28V, IOUT = 1mA to 50mA (Note 2) 4.90 5 5.10 5.6V VS 40V, t 1s, IOUT = 1mA to 30mA (Note 2) 4.9 5 5.1 VS = +8V, IOUT = 1mA to 100mA 4.9 5 5.1 IOUT = 10mA 0.1 0.25 IOUT = 50mA 0.2 0.4 IOUT = 100mA 0.3 0.5 VS = +4.75V VS to VOUT Difference in Undervoltage VIO VS = +4V, IOUT = 35mA Line Regulation VOL +5.5V VS +28V, IOUT = 1mA Load Regulation VOLO Current Limit Quiescent Current Shutdown Supply Current ISHDN Thermal-Shutdown Temperature TJ(SHDN) Thermal-Shutdown Hysteresis TJ(SHDN) 2 1mA IOUT 100mA V V 0.4 V 5 mV 17 50 mV 260 400 mA IOUT = 100A 46 100 IOUT = 300A 45 100 IOUT = 100mA 4.5 10 mA VEN +0.4V 17 30 A ILIM IQ 0.6 UNITS 160 Temperature rising A +165 C 20 C _______________________________________________________________________________________ 28V, 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output (VS = +14V, VOUT = 5V, EN unconnected, TA = TJ = -40C to +125C, CIN = 10F, COUT = 10F, unless otherwise noted. Typical specifications are at TA = +25C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 85 90 94.5 %VOUT 30 65 100 mV 55 110 180 ms RESET Reset Threshold Voltage Reset Threshold Hysteresis VRT VOUT falling VRTH Reset Pulse Delay tRD CCT = 100nF, tR 100s RES Output Low Voltage VRL VS +1.5V,RRES = 10k to VOUT 0.4 V RES Output High Leakage Current IRH VRES = 5V 1.0 A Delay Comparator Threshold VCTTH VCT rising 2.4 V 1.9 Delay Comparator Threshold Hysteresis 2.1 100 mV SENSE Sense Threshold VST VSI falling Sense Threshold Hysteresis 1.10 1.16 1.24 V 50 100 150 mV 0.4 V 1 A +1 A Sense Output Low Voltage VSL VSI 1.10V, VS 4V, RSO = 10k to VOUT Sense Output Leakage Current ISH VSO = 5V, VSI 1.5V Sense Input Current ISI VSI = 3.3V -1 EN = high, regulator on 2.4 ENABLE Enable Voltage VEN Enable Internal Pullup Current IEN EN = low, regulator off EN is internally pulled up to 3.6V (max) 0.4 3 V A _______________________________________________________________________________________ 3 MAX5091 ELECTRICAL CHARACTERISTICS (MAX5091A) (continued) MAX5091 28V, 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output ELECTRICAL CHARACTERISTICS (MAX5091B) (VS = +14V, VOUT = 3.3V, EN unconnected, TA = TJ = -40C to +125C, CIN = 10F, COUT = 10F, unless otherwise noted. Typical specifications are at TA = +25C.) (Note 1) PARAMETER Output Voltage SYMBOL VOUT MIN TYP MAX TA = +25C, IOUT = 1mA CONDITIONS 3.267 3.3 3.333 5V VS 28V, IOUT = 1mA to 50mA (Note 2) 3.234 3.3 3.366 5V VS 40V, t < 1s, IOUT = 1mA to 30mA (Note 2) 3.234 3.3 3.366 VS = +8V, IOUT = 1mA to 100mA 3.234 3.3 3.366 UNITS V VS to VOUT Difference in Undervoltage VIO VS = 3.5V, IOUT = 35mA 0.2 0.4 V Line Regulation VOL 5V VS 28V, IOUT = 1mA 0.6 5 mV Load Regulation VOLO Current Limit Quiescent Current 1mA IOUT 100mA 11 40 mV 260 400 mA IOUT = 100A 45 100 IOUT = 300A 45 100 IOUT = 100mA 4.4 10 mA VEN 0.4V 17 30 A ILIM IQ Shutdown Supply Current ISHDN Thermal-Shutdown Temperature TJ(SHDN) Thermal-Shutdown Hysteresis TJ(SHDN) 160 Temperature rising A +165 C 20 C RESET CIRCUIT Reset Threshold Voltage Reset Threshold Hysteresis VRT VOUT falling VRTH 85 90 94.5 %VOUT 20 45 80 mV 55 105 Reset Pulse Delay tRD CCT = 100nF, tR 100s 180 ms RES Output-Low Voltage VRL VS 1.5V, RRES = 4k to VOUT 0.4 V RES Output-High Leakage Current IRH VRES = 3.3V 1.0 A Delay Comparator Threshold VCTTH 2.4 V Delay Comparator Threshold Hysteresis 4 VCT rising 1.9 2.1 100 _______________________________________________________________________________________ mV 28V, 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output (VS = +14V, VOUT = 3.3V, EN unconnected, TA = TJ = -40C to +125C, CIN = 10F, COUT = 10F, unless otherwise noted. Typical specifications are at TA = +25C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 1.09 1.15 1.23 V 50 100 150 mV 0.4 V 1 A +1 A SENSE Sense Threshold VST VSI falling Sense Threshold Hysteresis Sense Output-Low Voltage VSL VSI 1.09V, VS 4V, RSO = 10k to VOUT Sense Output Leakage Current ISH VSO = 3.3V, VSI 1.5V Sense Input Current ISI VSI = 3.3V -1 EN = high, regulator on 2.4 ENABLE Enable Voltage VEN Enable Internal Pullup Current IEN EN = low, regulator off V 0.4 EN is internally pulled up to 3.6V (max) 3 A Note 1: Limits at TA = -40C are guaranteed by design and not production tested. Note 2: Maximum output current is limited by the power dissipation capability of the package. Typical Operating Characteristics (Typical Application Circuit, VS = +14V, CIN = 10F, COUT = 10F, VSI = 0V, VEN = +2.4V, VOUT = +5V, TA = +25C, unless otherwise noted.) VOUT AT NO LOAD, 100A, 1mA, 10mA, 100mA 5 MAX5091 toc02 MAX5091A MAX5091 toc01 VOUT AT NO LOAD, 100A, 1mA, 10mA, 100mA OUTPUT VOLTAGE vs. OUTPUT CURRENT OUTPUT VOLTAGE vs. INPUT VOLTAGE 4 MAX5091B MAX5091A 5.04 5.02 3 MAX5091 toc03 OUTPUT VOLTAGE vs. INPUT VOLTAGE 6 VS = 14V 4 VOUT (V) VOUT (V) VOUT (V) 5.00 2 4.98 4.96 3 VS = 6V 4.94 1 4.92 2 4.90 0 0 5 10 VS (V) 15 0 1 2 3 VS (V) 4 5 6 0.01 0.1 1 10 100 IOUT (mA) _______________________________________________________________________________________ 5 MAX5091 ELECTRICAL CHARACTERISTICS (MAX5091B) (continued) Typical Operating Characteristics (continued) (Typical Application Circuit, VS = +14V, CIN = 10F, COUT = 10F, VSI = 0V, VEN = +2.4V, VOUT = +5V, TA = +25C, unless otherwise noted.) OUTPUT VOLTAGE vs. TEMPERATURE QUIESCENT CURRENT vs. INPUT VOLTAGE 100 4.975 IOUT = 10mA 4.950 TA = +25C, +85C 100 TA = -40C 10 TA = -40C 10 IOUT = 100mA 4.925 EN = OPEN IOUT = 100A EN = OPEN IOUT = NO LOAD 4.900 1 10 35 60 85 110 2 6 10 14 18 22 26 30 1 34 38 2 6 10 14 18 22 26 30 34 38 TEMPERATURE (C) VS (V) VS (V) RESET OUTPUT LOW vs. TEMPERATURE QUIESCENT CURRENT vs. OUTPUT CURRENT SHUTDOWN SUPPLY CURRENT vs. INPUT VOLTAGE 10 MAX5091 toc07 0.25 RRES = 4k 0.20 135 VS = 14V TA = +25C 40 MAX5091 toc09 -15 MAX5091 toc08 -40 VS = 14V TA = +25C EN = 0V 30 0.15 ISHDN (A) 1 IQ (mA) RESET OUTPUT LOW (V) TA = +125C TA = +125C IQ (A) VOUT (V) TA = +25C, +85C IOUT = 1mA 5.000 1000 MAX5091 toc06 IOUT = 100A 1000 IQ (A) 5.025 QUIESCENT CURRENT vs. INPUT VOLTAGE MAX5091 toc05 MAX5091A MAX5091 toc04 5.050 0.10 RRES = 10k 20 0.1 10 0.05 0.1 -40 -25 -10 5 20 35 50 65 80 95 110 125 0 100 10 20 30 DROPOUT VOLTAGE vs. LOAD CURRENT DROPOUT VOLTAGE vs. LOAD CURRENT DROPOUT VOLTAGE (mV) 16 15 14 -5 -30 65 TEMPERATURE (C) 100 135 MAX5091A VS = 4.75V DROPOUT VOLTAGE (mV) MAX5091 toc10 17 325 300 275 250 225 200 175 150 125 100 75 50 25 0 0.1 1 10 IOUT (mA) 100 300 275 250 225 200 175 150 125 100 75 50 25 0 MAX5091B VS = 3.3V 0.1 40 MAX5091 toc12 SHUTDOWN SUPPLY CURRENT vs. TEMPERATURE MAX5091 toc11 VS (V) 18 -40 10 IOUT (mA) VS = 14V EN = 0V 19 1 TEMPERATURE (C) 20 6 0 0.01 0 ISHDN (A) MAX5091 28V, 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output 1 10 IOUT (mA) _______________________________________________________________________________________ 100 28V, 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output IOUT = 100mA 200 150 100 50 MAX5091 toc14 4 4.54 4.52 VOUT RISING 4.50 4.48 4.44 30 65 100 0 -40 135 -5 30 65 100 SENSE OUTPUT vs. SENSE INPUT POWER-SUPPLY REJECTION RATIO vs. SUPPLY CURRENT MAX5091 toc16 5 4 VIN = 14V IOUT = 10mA 500mVP-P -10 1.20 1.15 1.10 VSI RISING 3 PSRR (dB) SENSE OUTPUT (V) 1.25 VSI FALLING 2 -30 -40 -50 -60 1 SI INPUT FALLING -70 1.00 0 65 0 -20 1.30 30 4.7 4.6 SENSE THRESHOLD vs. TEMPERATURE SI INPUT RISING -5 4.5 VOUT (V) 1.40 -40 4.4 TEMPERATURE (C) 1.45 1.05 4.3 135 TEMPERATURE (C) 1.50 1.35 VOUT RISING 1 VOUT FALLING MAX5091 toc17 -5 VOUT FALLING 2 4.40 -40 3 4.46 4.42 IOUT = 10mA 0 SENSE THRESHOLD (V) 4.56 MAX5091A RRES = 10k TO OUT 5 MAX5091 toc18 250 MAX5091A 4.58 VRES (V) 300 4.60 RESET THRESHOLD VOLTAGE (V) MAX5091A VS = 4.75V 350 DROPOUT VOLTAGE (mV) MAX5091 toc13 400 RESET VOLTAGE vs. OUTPUT VOLTAGE MAX5091 toc15 RESET THRESHOLD vs. TEMPERATURE DROPOUT VOLTAGE vs. TEMPERATURE 100 135 -80 1.0 1.1 TEMPERATURE (C) 1.2 1.3 1.4 0.01 SENSE INPUT (V) LOAD-TRANSIENT RESPONSE 10 100 LINE-TRANSIENT RESPONSE MAX5091 toc20 VOUT 5V AC-COUPLED 200mV/div IOUT = 1mA VOUT 5V AC-COUPLED 100mV/div 40V 50mA 200s/div 1 FREQUENCY (kHz) MAX5091 toc19 CIN = 10F COUT = 10F/10m ESR ISTEP = 100A TO 50mA 0.1 IOUT 20mA/div VS 10V/div 100A 14V 200s/div _______________________________________________________________________________________ 7 MAX5091 Typical Operating Characteristics (continued) (Typical Application Circuit, VS = +14V, CIN = 10F, COUT = 10F, VSI = 0V, VEN = +2.4V, VOUT = +5V, TA = +25C, unless otherwise noted.) MAX5091 28V, 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output Typical Operating Characteristics (continued) (Typical Application Circuit, VS = +14V, CIN = 10F, COUT = 10F, VSI = 0V, VEN = +2.4V, VOUT = +5V, TA = +25C, unless otherwise noted.) VOUT STARTUP RESPONSE SHUTDOWN RESPONSE ENABLE RESPONSE MAX5091 toc21 MAX5091 toc23 MAX5091 toc22 IOUT = 100mA IOUT = 10mA VOUT 2V/div IOUT = 100mA VOUT 2V/div VOUT 5V/div 0V 0V 0V VS 5V/div 0V 0V 10ms/div EN 2V/div EN 5V/div 0V 200s/div 200s/div Pin Description PIN 8 NAME FUNCTION 1 VS Regulator Input. Operating supply range is from +5V to +28V and withstands 40V transients. Bypass VS to GND with a 10F capacitor. 2 SI Voltage Sense/Power-Fail Comparator Input. SI is the noninverting input of an uncommitted comparator. SO asserts low if VSI drops below the reference level, VST. 3 EN Enable Input. Leave unconnected (or pull EN high) to turn on the regulator. Pull EN low to place the device in shutdown mode. EN is internally pulled up to 3.6V. 4 CT Reset Timeout Delay Capacitor Connection. Connect a capacitor from CT to GND to program the reset timeout period/reset pulse delay. During regulation, CT is pulled up to VOUT. CT is pulled low during reset, when EN is low, or when in thermal shutdown. 5 GND Ground. Bypass the input and output capacitors to the GND plane. Solder to large pads or the circuit-board ground plane to maximize thermal dissipation. 6 RES Active-Low Reset Output. Pull up externally to VOUT. Open-drain RES goes low when VOUT is below the reset threshold. Once output voltage is in regulation, RES goes high after the programmed reset timeout period is over. RES is low when EN is low or in thermal shutdown. 7 SO Voltage Sense/Power-Fail Comparator Output. Pull up externally to VOUT. Open-drain SO asserts low when VSI drops below the reference level, VST. SO also asserts low when EN is low or in thermal shutdown. 8 VOUT EP EP Regulator Output. Fixed at +5V (MAX5091A) or +3.3V (MAX5091B). Bypass with a 10F ceramic capacitor to GND. Exposed Paddle. EP is internally connected to GND. Connect EP to GND to provide a low thermal-resistance path from the IC junction to the PC board. Do not use as the only electrical connection to GND. _______________________________________________________________________________________ 28V, 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output MAX5091 LDO PASS ELEMENT VS VOUT VINT 3A MAX MAX5091 VREF GND ENABLE ALWAYS-ON EN VOUT ICT 2A PREREGULATOR ALWAYS-ON VINT 3.6V (MAX) DELAY COMPARATOR RES N N 2.1V 0.9 x VREF SCLIM FAULT DETECTION (TEMP AND SC) CT VREF 1.25V SD VREF SO SI N VREF Figure 1. Functional Diagram _______________________________________________________________________________________ 9 MAX5091 28V, 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output Detailed Description Regulator The MAX5091 high-voltage, LDO regulator operates from +5V to +28V input voltage. The device withstands up to 40V transients, providing protection against temporary overvoltage conditions like load dump. The MAX5091 incorporates internal feedback resistors for factory-preset voltages of either +5V (MAX5091A) or +3.3V (MAX5091B). The regulator is capable of driving up to 100mA of load current and features a typical current limit of 260mA. The regulator uses a pnp pass element and provides low 0.5V dropout while delivering 100mA load current. The output of the regulator follows closely to the input during turn-on. See the Output Voltage vs. Input Voltage graph in the Typical Operating Characteristics. This makes the usable input voltage range for 3.3V and 5V output down to 3.7V and 5.5V, respectively. The MAX5091 is designed to operate with very low quiescent current during always-on operation when not in dropout. The regulator is stable with a wide variety of capacitors including low-ESR ceramic 10F (0603 case size). The load-transient response curves depict the stability of the LDO when using different capacitance and ESR ranges. See the Capacitor Selection and Regulator Stability section in the Applications Information. Reset Output (RES) The MAX5091 integrates a power-on-reset circuit. RES is an open-drain output that requires a pullup resistor to VOUT. The open-drain MOSFET can sink up to 825A current while keeping the RES voltage below 0.4V. The internal reset circuit monitors the regulator output voltage and RES asserts an active-low output when the regulator output falls below a reset threshold of typically 0.9 x VOUT. The RES output remains low when VOUT is below the reset threshold, and remains low for the duration of the reset timeout period (tRD). The reset timeout period is programmable and can be set with an external capacitor connected from CT to ground. The duration of the delay as a function of CT is: tRD = CCT x VCCTH + (35 x 10-6 ) ICT where VCCTH = 2.1V and ICT = 2 x 10-6 A. The default reset timeout period is 35s when no capacitor is connected from CT to ground. 10 SI/SO Comparator The MAX5091 includes an uncommitted comparator for monitoring the input voltage or for detecting power-fail conditions. The input SI is the noninverting input of the comparator. The open-drain output SO asserts low when voltage at the input SI drops below the threshold voltage, VST (see Figure 1). The sense comparator typically has a hysteresis of 100mV. Use the following equation to calculate the resistor-divider for programming the trip voltage (VTRIP) during power-fail. See the Typical Application Circuit. VTRIP = (VST x RH ) + VST RL where VST = 1.16V (typ). Choose RL between 100k to 300k. Enable Input The enable (EN) is a TTL-compatible logic input. Logic low at EN turns off the regulator and reduces the current consumption to 17A (typ). It is internally pulled up to a logic-high voltage (3.6V max) by an internal resistor. Thus, the MAX5091 is enabled by default when VS is applied and EN is left unconnected. The regulator, reset supervisor circuit, and the sense comparator can be manually shut down by pulling EN low. For shutdown operation, the pulldown network must be capable of sinking 3A max, since the internal pullup resistor sets the maximum pullup current at 3A. The external pulldown device should not leak more than 1A current when it is in the off-state. Current Limit The MAX5091 features a current limiter that monitors the output current and controls the pass transistor's gate voltage, limiting the output current to typically 260mA. The output can be continuously shorted to ground without damaging the device at VS 16V. Note that the output short-circuit current may increase the power dissipation significantly and raise the junction temperature to its thermal-shutdown threshold. In such a case, the MAX5091 is temporarily turned off. Thermal Shutdown When the junction temperature exceeds TJ = +165C (typ), an internal thermal sensor signals the shutdown logic to turn off the pass transistor and allow the IC to cool. The thermal sensor turns the pass transistor on again after the IC's junction temperature cools by +20C (typ), resulting in a cycled output during continuous thermal-overload conditions. Thermal shutdown protects the MAX5091 in the event of fault conditions. For continuous operation, do not exceed the absolute maximum junction temperature of TJ = +150C. ______________________________________________________________________________________ 28V, 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output Available Output Current Calculation The MAX5091 high-voltage regulator provides up to 100mA of output current. The input voltage extends to +28V. Package power dissipation limits the amount of output current available for a given input/output voltage and ambient temperature. Figure 2 depicts the maximum power dissipation curve for the 8-pin SO-EP package. The graph assumes that the exposed metal back of the MAX5091 package is soldered to copper on a single layer PCB according to the JEDEC51 standard. Use Figure 2 to determine the allowable package dissipation for a given ambient temperature. Alternately, use the following formula to calculate the allowable package dissipation: 2.0 8-PIN SO-EP 1.8 1.538W 1.6 IOUT(MAX) PD VS - VOUT The above equations do not include the power dissipation from self-heating due to the IC ground current. The junction-to-ambient thermal impedance depends on the area of the copper plane, its thickness, and the number of copper layers on PCB. For the higher power dissipation requirement, use multiple-layered PCBs with 2oz copper and a large copper area. Capacitor Selection and Regulator Stability For stable operation over the full temperature range and with load currents up to 100mA, use a 10F output capacitor with a low ESR. Table 1 shows a list of recommended output capacitor ESR for various load conditions. Table 1. Recommended Output Capacitor ESR RECOMMENDED COUT ESR 1.4 PD (W) MAX5091 fig02 1.538W For TA + 70C PD = 1.538 - 0.01923 (TA - 70 C) For + 70 C < TA + 125C After determining the allowable package dissipation, calculate the maximum output current using the following formula: DERATE 19.23mW/C IOUT VOUT = 3.3V 1.0 IOUT 10mA CESR < 0.66 CESR < 1 0.8 IOUT 50mA CESR < 0.132 CESR < 0.2 0.6 IOUT 100mA CESR < 66m CESR < 0.1 1.2 VOUT = 5.0V 0.4 0.2 0 10 20 30 40 70 90 110 130 150 60 80 100 120 140 TEMPERATURE (C) 50 Figure 2. 8-Pin SO-EP Maximum Power Dissipation vs. Temperature ______________________________________________________________________________________ 11 MAX5091 Applications Information 28V, 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output MAX5091 Pin Configurations (continued) Chip Information PROCESS: BiCMOS TOP VIEW VS 1 SI 2 + 8 VOUT 7 SO 6 RES 5 GND MAX5091 EN 3 CT 4 EXPOSED PADDLE SO-EP 12 ______________________________________________________________________________________ 28V, 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output 8L, SOIC EXP. PAD.EPS PACKAGE OUTLINE 8L SOIC, .150" EXPOSED PAD 21-0111 C 1 ______________________________________________________________________________________ 1 13 MAX5091 Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.) Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.) 6, 8, &10L, DFN THIN.EPS MAX5091 28V, 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output PACKAGE OUTLINE, 6,8,10 & 14L, TDFN, EXPOSED PAD, 3x3x0.80 mm 21-0137 14 ______________________________________________________________________________________ H 1 2 28V, 100mA, Low-Quiescent-Current LDO with Reset and Power-Fail Input/Output COMMON DIMENSIONS PACKAGE VARIATIONS SYMBOL MIN. MAX. PKG. CODE N D2 E2 e JEDEC SPEC b A 0.70 0.80 T633-1 6 1.500.10 2.300.10 0.95 BSC MO229 / WEEA 0.400.05 1.90 REF D 2.90 3.10 T633-2 6 1.500.10 2.300.10 0.95 BSC MO229 / WEEA 0.400.05 1.90 REF [(N/2)-1] x e E 2.90 3.10 T833-1 8 1.500.10 2.300.10 0.65 BSC MO229 / WEEC 0.300.05 1.95 REF A1 0.00 0.05 T833-2 8 1.500.10 2.300.10 0.65 BSC MO229 / WEEC 0.300.05 1.95 REF L 0.20 0.40 T833-3 8 1.500.10 2.300.10 0.65 BSC MO229 / WEEC 0.300.05 1.95 REF T1033-1 10 1.500.10 2.300.10 0.50 BSC MO229 / WEED-3 0.250.05 2.00 REF k 0.25 MIN. A2 0.20 REF. T1033-2 10 1.500.10 2.300.10 0.50 BSC MO229 / WEED-3 0.250.05 2.00 REF T1433-1 14 1.700.10 2.300.10 0.40 BSC ---- 0.200.05 2.40 REF T1433-2 14 1.700.10 2.300.10 0.40 BSC ---- 0.200.05 2.40 REF PACKAGE OUTLINE, 6,8,10 & 14L, TDFN, EXPOSED PAD, 3x3x0.80 mm -DRAWING NOT TO SCALE- 21-0137 H 2 2 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 15 (c) 2006 Maxim Integrated Products Heaney is a registered trademark of Maxim Integrated Products, Inc. MAX5091 Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.)