MAX1819EBL25-T

19-2072; Rev 0; 1/02 500mA Low-Dropout Linear Regulator in UCSP The MAX1819 low-dropout linear regulator operates from a 2.5V to 5.5V supply and delivers a guaranteed 500mA load current with low 120mV dropout. The high-accuracy (±1%) output voltage is preset at an internally trimmed voltage (see the Selector Guide) or can be adjusted from 1.25V to 5V with an external resistive-divider. An internal PMOS pass transistor allows the low 125µA supply current to remain independent of load, making this device ideal for portable battery-operated equipment such as personal digital assistants (PDAs), cellular phones, cordless phones, base stations, and notebook computers. Other features include an active-low, open-drain reset output that indicates when the output is out of regulation, a 0.1µA shutdown, short-circuit protection, and thermal shutdown protection. The device is available in a miniature 6-pin UCSP™ package. Applications Notebook Computers Cellular and Cordless Telephones Features ♦ Guaranteed 500mA Output Current ♦ Low 90mV Dropout at 500mA ♦ ±1% Initial Output Accuracy ♦ Preset Output at 1.5V, 1.8V, 2V, 2.5V, 3.3V, 5V ♦ Adjustable Output from 1.25V to 5V ♦ Power-OK Output ♦ Low 125µA Ground Current ♦ 0.1µA Shutdown Current ♦ Thermal Overload Protection ♦ Output Current Limit ♦ Tiny 840mW 6-Pin UCSP Package Ordering Information PART MAX1819EBL_ _ -T* TEMP RANGE PIN-PACKAGE -40°C to +85°C 6 UCSP *Insert the desired two-digit suffix (see Selector Guide) into the blanks to complete the part number. Personal Digital Assistants (PDAs) Palmtop Computers Selector Guide Base Stations USB Hubs PART AND SUFFIX Docking Stations UCSP is a trademark of Maxim Integrated Products, Inc. VOUT UCSP MARK MAX1819EBL 15 1.5V or Adj AAH MAX1819EBL 18 1.8V or Adj AAG MAX1819EBL 20 2V or Adj AAC MAX1819EBL 25 2.5V or Adj AAD MAX1819EBL 33 3.3V or Adj AAE MAX1819EBL 50 5V or Adj AAF Pin Configuration Typical Operating Circuit TOP VIEW (TOP OF PC BOARD/ BALLS SOLDERED DOWN) A 1 2 3 IN A1 POK A2 SHDN A3 VIN = 2.5V TO 5.5V IN NC COUT 3.3µF CIN 1µF MAX1819 B MAX1819 OUT C C1 SET C2 VOUT OUT RPOK 100kΩ ON GND C3 SHDN POK SET GND OFF TO µC UCSP ________________________________________________________________ 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 MAX1819 General Description MAX1819 500mA Low-Dropout Linear Regulator in UCSP Linear Regulator in ABSOLUTE MAXIMUM RATINGS IN, SHDN, POK, SET to GND ...................................-0.3V to +6V OUT to GND ................................................-0.3V to (VIN + 0.3V) Output Short-Circuit Duration ...............................................1min Continuous Power Dissipation (TA = +70°C) (Note 1) 6-Pin UCSP (derate 10.5mW/°C above +70°C) ............840mW Operating Temperature Range ...........................-40°C to +85°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Soldering Temperature (10s) ...........................................+300°C Note 1: Thermal properties are specified with product mounted on PC board with one square-inch of copper area and still air. 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 (VIN = (VOUT + 500mV) or VIN = 2.5V, whichever is greater; SHDN = IN, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2) PARAMETER Input Voltage Input Undervoltage Lockout Output Voltage Accuracy (Preset Mode) SYMBOL CONDITIONS VIN VUVLO VOUT MIN TYP 2.5 +1 IOUT = 100mA, TA = +25°C, VOUT < 2V -1.5 +1.5 IOUT = 100mA, TA = -40°C to +85°C -2.5 +2.5 -3 +3 1.25 5.00 VIN = 2.7V, IOUT = 100mA, VOUT set to 2V TA = 0°C to +85°C 1.225 TA = -40°C to +85°C 1.213 1.250 Guaranteed Output Current (RMS) IOUT VIN ≥ 2.7V 500 Short-Circuit Current Limit ILIM VOUT = 0, VIN ≥ 2.7V 0.55 1.39 50 100 VOUT > 96% of nominal value, VIN ≥ 2.7V Dropout Voltage (Note 3) Line Regulation IQ VIN - VOUT ∆VLNR VSET = 1.25V 1.275 mA 2.50 A 150 mV +100 nA 2 -100 125 IOUT = 500mA 150 A 250 VOUT = 5V 125 220 VOUT = 3.3V 133 232 VOUT = 2.5V 165 280 0 +0.15 VIN from (VOUT + 100mV) to 5.5V, ILOAD = 5mA -0.15 Dual Mode is a trademark of Maxim Integrated Products, Inc. 2 V 1.288 IOUT = 100µA IOUT = 500mA % V SET Dual Mode™ Threshold Ground-Pin Current V -1 VSET ISET 2.3 2.0 SET Voltage Threshold (Adjustable Mode) SET Input Bias Current V IOUT = 100mA, TA = +25°C, VOUT ≥ 2V Adjustable Output Voltage Range In-Regulation Current Limit UNITS 5.5 Rising, 75mV hysteresis IOUT = 1mA to 500mA, VIN > VOUT + 0.5V, TA = -40°C to +85°C 2.15 MAX _______________________________________________________________________________________ µA mV %/V 500mA Low-Dropout Linear Regulator in UCSP (VIN = (VOUT + 500mV) or VIN = 2.5V, whichever is greater; SHDN = IN, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2) PARAMETER SYMBOL TYP MAX UNITS IOUT = 1mA to 500mA 0.4 1.0 % 10Hz to 1MHz, COUT = 3.3µF (ESR < 0.1Ω) 115 IOFF SHDN = GND, VIN = 5.5V 0.1 VIH 2.5V < VIN < 5.5V VIL 2.5V < VIN < 5.5V ∆VLDR Load Regulation Output Voltage Noise CONDITIONS MIN µVRMS SHUTDOWN Shutdown Supply Current SHDN Input Threshold SHDN Input Bias Current I SHDN 15 µA 1.6 V 0.6 SHDN = IN or GND, TA = +25°C 1 TA = +85°C 5 70 nA POK OUTPUT POK Output Low Voltage VOL POK sinking 1mA Operating Voltage Range for Valid POK 0.01 POK sinking 100µA 1.0 POK Output High Leakage Current POK = 5.5V, TA = +25°C 1 TA = +85°C 5 POK Threshold Rising edge, referred to VOUT(NOMINAL) 90 0.1 V 5.5 V 30 93 nA 96 % THERMAL PROTECTION Thermal Shutdown Temperature Thermal Shutdown Hysteresis TSHDN 170 °C ∆TSHDN 20 °C Note 2: All devices are 100% production tested at TA = +25°C and up to 100mA. Limits over the operating temperature range and above 100mA are guaranteed by design. Note 3: The dropout voltage is defined as VIN - VOUT, when VOUT is 100mV below the value of VOUT measured for VIN = VOUT(NOM) + 500mV. Since the minimum input voltage is 2.5V, this specification is only meaningful when VOUT(NOM) > 2.5V. For VOUT(NOM) between 2.5V and 3.5V, use the following equations: Typical Dropout = -40mV/V ✕ VOUT(NOM) + 265mV; Guaranteed Maximum Dropout = -60mV/V ✕ VOUT(NOM) + 430mV. For VOUT(NOM) > 3.5V, Typical Dropout = 125mV; Maximum Dropout = 220mV. Typical Operating Characteristics (VIN = (VOUT + 500mV) or 2.5V, whichever is greater; SHDN = IN, CIN = 3.3µF, COUT = 3.3µF, TA = +25°C, unless otherwise noted.) 175 150 125 100 2.5V OUTPUT 1.8V OUTPUT 75 50 3.3V OUTPUT 175 165 2.5V OUTPUT 155 145 1.8V OUTPUT 135 0 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 INPUT VOLTAGE (V) ILOAD = 150mA 170 5V OUTPUT 160 150 1.5V OUTPUT 140 125 25 180 GROUND-PIN CURRENT (µA) 3.3V OUTPUT 200 MAX1819 toc02 IOUT = 150mA GROUND-PIN CURRENT (µA) GROUND-PIN CURRENT (µA) 225 MAX1819 toc01 250 GROUND-PIN CURRENT vs. TEMPERATURE GROUND-PIN CURRENT vs. LOAD CURRENT MAX1819 toc03 GROUND-PIN CURRENT vs. INPUT VOLTAGE 115 130 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 LOAD CURRENT (A) -40 -15 10 35 60 85 TEMPERATURE (°C) _______________________________________________________________________________________ 3 MAX1819 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (continued) (VIN = (VOUT + 500mV) or 2.5V, whichever is greater; SHDN = IN, CIN = 3.3µF, COUT = 3.3µF, TA = +25°C, unless otherwise noted) TA = +85°C TA = +25°C TA = -40°C 60 40 20 0 0.6 0.4 0.2 0 VOUT = 1.8V -0.2 -0.4 VOUT = 3.3V -0.6 -0.8 0.5 0.4 COUT = 3.3µF 60 0 -0.1 -0.2 -0.3 -40 -15 10 35 60 LINE TRANSIENT LOAD TRANSIENT RESPONSE MAX1819 toc08 MAX1819 toc09 VOUT = 2.5V IOUT = 5mA VIN = 3.8V VOUT = 3.3V VOUT 10mV/div VOUT = 3.3V IOUT 380mA 50mA RLOAD = 100Ω 50 40 3.5V 30 3V VIN 20 VOUT 20mV/div 10 0 0.01 0.1 1 10 100 100µs/div 1000 40µs/div FREQUENCY (kHz) LOAD TRANSIENT RESPONSE NEAR DROPOUT POWER-ON RESET MAX1819 toc10 MAX1819 toc11 VPOK VIN = 3.35V VOUT = 3.5V 50mV/div VOUT 0 VOUT IOUT 200mA 2V/div 0 VIN 20mA 0 40µs/div 4 85 TEMPERATURE (°C) LOAD CURRENT (A) MAX1819 toc07 70 0.1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 POWER-SUPPLY REJECTION RATIO vs. FREQUENCY 80 0.2 -0.5 0 100 200 300 400 500 600 700 800 LOAD CURRENT (A) ILOAD = 150mA 0.3 -0.4 VOUT = 0.5V -1.0 0 MAX1819 toc06 1.0 0.8 OUTPUT VOLTAGE ACCURACY (%) VOUT = 3.3V MAX1819 toc05 MAX1819 toc04 260 240 220 200 180 160 140 120 100 80 OUTPUT VOLTAGE ACCURACY vs. TEMPERATURE OUTPUT VOLTAGE ACCURACY vs. LOAD CURRENT OUTPUT VOLTAGE ACCURACY (%) DROPOUT VOLTAGE (mV) DROPOUT VOLTAGE vs. LOAD CURRENT PSRR (dB) MAX1819 500mA Low-Dropout Linear Regulator in UCSP 10ms/div _______________________________________________________________________________________ 500mA Low-Dropout Linear Regulator in UCSP (VIN = (VOUT + 500mV) or 2.5V, whichever is greater; SHDN = IN, CIN = 3.3µF, COUT = 3.3µF, TA = +25°C, unless otherwise noted) SHORT-CIRCUIT CURRENT LIMIT vs. SUPPLY VOLTAGE SHUTDOWN WAVEFORM MAX1819 toc12 MAX1819 toc13 1.40 SHUTDOWN VOLTAGE 0 2V/div VOUT 0 POK SHORT-CIRCUIT CURRENT LIMIT (A) VOUT(NOM) = 2V 1.39 1.38 1.37 1.36 0 1.35 200µs/div 2.5 3.0 3.5 4.0 4.5 5.0 5.5 SUPPLY VOLTAGE (V) Pin Description PIN NAME FUNCTION A1 IN A2 POK Open-Drain POK Output. POK remains low while the output voltage (VOUT) is below the POK threshold. Connect a 100kΩ pullup resistor from POK to OUT to obtain an output voltage. A3 SHDN Active-Low Shutdown Input. A logic low reduces supply current below 15µA. In shutdown, the POK and OUT are low. Connect to IN for normal operation. C1 OUT Regulator Output. Sources up to 500mA. Bypass with a 3.3µF low-ESR capacitor to GND. Use a 4.7µF capacitor for output voltages below 2V. C2 SET Voltage-Setting Input. Connect to GND for preset output. Connect to a resistive voltage-divider between OUT and GND to set the output voltage between 1.25V and 5V. C3 GND Ground Regulator Input. Supply voltage can range from 2.5V to 5.5V. Bypass with a 1µF capacitor to GND (see the Capacitor Selection and Regulator Stability section). Detailed Description The MAX1819 is a low-dropout, low-quiescent-current linear regulator designed primarily for battery-powered applications. The device supplies loads up to 500mA and is available with preset output voltages. As illustrated in Figure 1, the MAX1819 consists of a 1.25V reference, error amplifier, P-channel pass transistor, and internal feedback voltage-divider. The 1.25V reference is connected to the error amplifier, which compares this reference with the feedback voltage and amplifies the 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 and increases the output voltage. If the feedback voltage is too high, the pass-transistor gate is pulled up, allowing less current to pass to the output. The output voltage is fed back through either an internal resistive-divider connected to OUT or an external resistor network connected to SET. The Dual Mode comparator examines VSET and selects the feedback path. If VSET is below 50mV, the internal feedback path is used and the output is regulated to the factory-preset voltage. _______________________________________________________________________________________ 5 MAX1819 Typical Operating Characteristics (continued) MAX1819 500mA Low-Dropout Linear Regulator in UCSP VIN = 2.5V TO 5.5V IN CIN 1µF THERMAL SENSOR MOSFET DRIVER WITH I LIM OUT ON VOUT = 1.25V TO 5V SHDN OFF COUT 3.3µF SHUTDOWN LOGIC 5kΩ VREF 1.25V ERROR AMPLIFIER LOGIC SUPPLY VOLTAGE (VOUT) RPOK 100kΩ R1 MAX1819 POK TO µC SET R2 93% VREF 100mV GND Figure 1. Functional Diagram Additional blocks include an output current limiter, thermal sensor, and shutdown logic. Internal P-Channel Pass Transistor The MAX1819 features a 0.25Ω 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 when the pass transistor saturates and use high base-drive currents under large loads. The MAX1819 does not suffer from these problems and consumes only 125µA of quiescent current under heavy loads as well as in dropout. Output Voltage Selection The MAX1819’s Dual Mode allows operation in either a preset voltage mode or an adjustable mode. Connect SET to GND to select the preset output voltage. The two-digit part number suffix identifies the output voltage 6 (see the Selector Guide). For example, the MAX1819EBL33 has a preset 3.3V output voltage. The output voltage may also be adjusted by connecting a voltage-divider from OUT to SET to GND (Figure 2). Select R2 in the 25kΩ to 100kΩ range. Calculate R1 with the following equation: R1 = R2 [(VOUT / VSET) - 1] where VSET = 1.25V, and VOUT may range from 1.25V to 5V. Shutdown Pull SHDN low to enter shutdown. During shutdown, the output is disconnected from the input and supply current drops to 0.1µA. When in shutdown, POK and OUT pull low. SHDN can be pulled as high as 6V, regardless of the input and output voltage. _______________________________________________________________________________________ 500mA Low-Dropout Linear Regulator in UCSP COUT 3.3µF MAX1819 R1 ON SHDN SET OFF R2 POK MAXIMUM OUTPUT CURRENT (mA) CIN 1µF 600 OUT TA = +85°C TA = +70°C MAXIMUM RECOMMENDED OUTPUT CURRENT MAX1819 fig03 IN MAXIMUM OUTPUT CURRENT vs. INPUT VOLTAGE (POWER DISSIPATION LIMIT) VOUT -1 1.25V VOUT 400 VOUT = 1.8V 200 VOUT = 2.5V VOUT = 3.3V MAXIMUM INPUT VOLTAGE V IN = 2.5V TO 5.5V MAX1819 R1 = R2 0 GND 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 INPUT VOLTAGE (V) Figure 2. Adjustable Output Using External Feedback Resistors Figure 3. Power Operating Regions—Maximum Output vs. Supply Voltage POK Output Operating Region and Power Dissipation The power-OK (POK) output pulls low when OUT is less than 93% of the nominal regulation voltage. Once OUT exceeds 93% of the nominal voltage, POK goes high impedance. POK is an open-drain N-channel output. To obtain a voltage signal, connect a pullup resistor from POK to OUT. A 100kΩ resistor works well for most applications. POK can be used as a power-OK signal to a microcontroller (µC), or drive an external LED to indicate power failure. When the MAX1819 is shut down, POK is held low independent of the output voltage. If unused, leave POK grounded or unconnected. The MAX1819’s maximum power dissipation depends on the thermal resistance of the IC package and circuit board, the temperature difference between the die junction and ambient air, and the rate of air flow. The power dissipated in the device is P = I OUT × (VIN V OUT ). The maximum allowed power dissipation is 840mW at TA = +70°C or: Current Limit The MAX1819 monitors and controls the pass transistor’s gate voltage, limiting the output current to 1.0A (typ). This current limit doubles when the output voltage is within 4% of the nominal value to improve performance with large load transients. Thermal Overload Protection Thermal overload protection limits total power dissipation in the MAX1819. When the junction temperature exceeds TJ = +170°C, a thermal sensor turns off the pass transistor, allowing the IC to cool. The thermal sensor turns the pass transistor on again after the junction temperature cools by 20°C, resulting in a pulsed output during continuous thermal overload conditions. Thermal overload protection protects the MAX1819 in the event of fault conditions. For continuous operation, do not exceed the absolute maximum junction-temperature rating of TJ = +150°C. PMAX = (TJ(MAX) - TA) / ( θJB + θBA) where TJ - TA is the temperature difference between the MAX1819 die junction and the surrounding air, θJB is the thermal resistance of the junction to the base, and θ BA is the thermal resistance through the PC board, copper traces, and other materials to the surrounding air. For best heatsinking, the copper area should be equally shared between the IN, OUT, and GND pins. The MAX1819 delivers up to 0.5A RMS and operates with input voltages up to 5.5V, but not simultaneously. High output currents can only be sustained when inputoutput differential voltages are low, as shown in Figure 3. _______________________________________________________________________________________ 7 MAX1819 500mA Low-Dropout Linear Regulator in UCSP Applications Information Capacitor Selection and Regulator Stability Capacitors are required at the MAX1819’s input and output for stable operation over the full temperature range and with load currents up to 500mA. Connect a 1µF capacitor between IN and ground and a 3.3µF lowESR capacitor between OUT and ground. For output voltages less than 2V, use a 4.7µF low-ESR output capacitor. The input capacitor (CIN) lowers the source impedance of the input supply. Reduce noise and improve load-transient response, stability, and powersupply rejection by using larger output capacitors, such as 10µF. The output capacitor’s (COUT) equivalent series resistance (ESR) affects stability and output noise. Use output capacitors with an ESR of 0.1Ω or less to ensure stability and optimum transient response. Surfacemount ceramic capacitors have very low ESR and are commonly available in values up to 10µF. C IN and COUT use short traces to connect to the MAX1819. The MAX1819 load-transient response (see the Typical Operating Characteristics) shows two components of the output response: a DC shift from the output impedance due to the load current change, and the transient response. Increasing the output capacitor’s value and decreasing the ESR attenuates the overshoot. Input-Output (Dropout) Voltage A regulator’s minimum input-to-output voltage differential (dropout voltage) determines the lowest usable supply voltage. In battery-powered systems, this determines the useful end-of-life battery voltage. Because the MAX1819 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 (see the Typical Operating Characteristics). VDROPOUT = VIN - VOUT = RDS(ON) × IOUT The MAX1819 ground current remains at approximately 150µA in dropout. Chip Information TRANSISTOR COUNT: 845 Noise, PSRR, and Transient Response The MAX1819 is designed to operate with low dropout voltages and low quiescent currents in battery-powered systems while still maintaining good noise, transient response, and AC rejection. See the Typical Operating Characteristics for a plot of Power-Supply Rejection Ratio (PSRR) vs. Frequency. When operating from noisy sources, improved supply-noise rejection and transient response can be achieved by increasing the values of the input and output bypass capacitors and through passive filtering techniques. 8 _______________________________________________________________________________________ 500mA Low-Dropout Linear Regulator in UCSP 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 ______________________9 © 2002 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products. MAX1819 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.)