a High Accuracy Ultralow IQ, 300 mA, anyCAP® Low Dropout Regulator ADP3333 FEATURES High Accuracy Over Line and Load: 0.8% @ 25C, 1.8% Over Temperature Ultralow Dropout Voltage: 230 mV (Max) @ 300 mA Requires Only CO = 1.0 F for Stability anyCAP = Stable with Any Type of Capacitor (Including MLCC) Current and Thermal Limiting Low Noise Low Shutdown Current: < 1 A 2.6 V to 12 V Supply Range –40C to +85C Ambient Temperature Range Ultrasmall 8-Lead MSOP Package FUNCTIONAL BLOCK DIAGRAM Q1 IN OUT ADP3333 THERMAL PROTECTION R1 CC gm DRIVER R2 SD BANDGAP REF GND APPLICATIONS Cellular Phones PCMCIA Cards Personal Digital Assistants (PDAs) DSP/ASIC Supplies GENERAL DESCRIPTION ADP3333 is a member of the ADP333x family of precision low dropout anyCAP voltage regulators. Pin-compatible with the MAX8860, the ADP3333 operates with a wider input voltage range of 2.6 V to 12 V and delivers a load current up to 300 mA. ADP3333 stands out from other conventional LDOs with a novel architecture and an enhanced process that enables it to offer performance advantages over its competition. Its patented design requires only a 1.0 µF output capacitor for stability. This device is insensitive to output capacitor Equivalent Series Resistance (ESR), and is stable with any good quality capacitor, including ceramic (MLCC) types for space-restricted applications. ADP3333 achieves exceptional accuracy of ± 0.8% at room temperature and ± 1.8% over temperature, line and load variations. The dropout voltage of ADP3333 is only 140 mV (typical) at 300 mA. This device also includes a safety current limit, thermal overload protection and a shutdown feature. In shutdown mode, the ground current is reduced to less than 1 µA. The ADP3333 has ultralow quiescent current, 70 µA (typ) in light load situations. ADP3333 NC VIN IN VOUT OUT CIN 1F SD GND COUT 1F OFF ON NC = NO CONNECT Figure 1. Typical Application Circuit anyCAP is a registered trademark of Analog Devices, Inc. REV. 0 Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781/329-4700 www.analog.com Fax: 781/326-8703 © Analog Devices, Inc., 2001 ADP3333–SPECIFICATIONS1 (V IN = 6.0 V, CIN = COUT = 1.0 F, TJ = –40C to +125C, unless otherwise noted) Parameter Symbol Condition Min OUTPUT Voltage Accuracy2 VOUT VIN = VOUTNOM 0.3 V to 12 V IL = 0.1 mA to 300 mA TJ = 25°C VIN = VOUTNOM 0.3 V to 12 V IL = 0.1 mA to 300 mA VIN = VOUTNOM 0.3 V to 12 V TJ = 25°C IL = 0.1 mA to 300 mA TJ = 25°C VOUT = 98% of VOUTNOM IL = 300 mA IL = 200 mA IL = 0.1 mA VIN = VOUTNOM + 1 V f = 10 Hz–100 kHz, CL = 10 µF IL = 300 mA Line Regulation2 Load Regulation Dropout Voltage Peak Load Current Output Noise GROUND CURRENT In Regulation In Dropout In Shutdown SHUTDOWN Threshold Voltage VDROP ILDPK VNOISE IGND IGND IGNDSD VTHSD SD Input Current ISD Output Current In Shutdown IOSD Max Unit 0.8 0.8 % –1.8 +1.8 % IL = 300 mA IL = 300 mA, TJ = 25°C IL = 300 mA, TJ = 85°C IL = 200 mA IL = 10 mA IL = 0.1 mA VIN = VOUTNOM – 100 mV IL = 0.1 mA, VIN = VOUTNOM – 100 mV IL = 0.1 mA, TJ = 0°C to 125°C SD = 0 V, VIN = 12 V ON OFF 0 ≤ SD ≤ 12 V 0 ≤ SD ≤ 5 V TJ = 25°C VIN = 12 V TJ = 125°C VIN = 12 V Typ 0.04 mV/V 0.04 mV/mA 140 105 30 600 45 230 185 mV mV mV mA µV rms 2.0 2.0 1.5 1.4 200 70 70 5.5 4.3 3.3 275 100 190 mA mA mA mA µA µA µA 70 160 µA 0.01 1 µA 0.85 0.8 0.01 0.01 0.4 7 4.5 1 1 V V µA µA µA µA 2.0 NOTES 1 Application stable with no load. 2 VIN = 2.6 V for models with VOUTNOM ≤ 2.3 V. Specifications subject to change without notice. –2– REV. 0 ADP3333 PIN FUNCTION DESCRIPTIONS ABSOLUTE MAXIMUM RATINGS* Input Supply Voltage . . . . . . . . . . . . . . . . . . . –0.3 V to +16 V Shutdown Input Voltage . . . . . . . . . . . . . . . . –0.3 V to +16 V Power Dissipation . . . . . . . . . . . . . . . . . . . Internally Limited Operating Ambient Temperature Range . . . . –40°C to +85°C Operating Junction Temperature Range . . . –40°C to +125°C JA (4-layer) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158°C/W JA (2-layer) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220°C/W Storage Temperature Range . . . . . . . . . . . . –65°C to +150°C Lead Temperature (Soldering, 10 sec) . . . . . . . . . . . . 300°C Vapor Phase (60 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . 215°C Infrared (15 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220°C Pin Mnemonic Function 1 OUT 2 IN 3 GND 4–6, 8 NC 7 SD *This is a stress rating only; operation beyond these limits can cause the device to be permanently damaged. Output of the Regulator. Bypass to ground with a 1.0 µF or larger capacitor. Input pin. Bypass to ground with a 1.0 µF or larger capacitor. Ground Pin No Connect Active Low Shutdown Pin. Connect to ground to disable the regulator output. When shutdown is not used, his pin should be connected to the input pin ORDERING GUIDE Model Output Voltage Package Option Branding Information ADP3333ARM-1.5 1.5 V RM-8 (MSOP-8) RM-8 (MSOP-8) RM-8 (MSOP-8) RM-8 (MSOP-8) RM-8 (MSOP-8) RM-8 (MSOP-8) RM-8 (MSOP-8) RM-8 (MSOP-8) LKA ADP3333ARM-1.8 1.8 V ADP3333ARM-2.5 2.5 V ADP3333ARM-2.77 2.77 V ADP3333ARM-3 3V ADP3333ARM-3.15 3.15 V ADP3333ARM-3.3 3.3 V ADP3333ARM-5 5V PIN CONFIGURATION OUT 1 IN 2 8 NC 7 SD TOP VIEW GND 3 (Not to Scale) 6 NC LKB NC* 4 5 LKC NC NC = NO CONNECT LKD *CAN BE CONNECTED TO ANY OTHER PIN. LKE LKF LKG LKH CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the ADP3333 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high-energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality. REV. 0 ADP3333 –3– WARNING! ESD SENSITIVE DEVICE ADP3333 –Typical Performance Characteristics 2.502 2.502 VOUT = 2.5V 0mA 2.498 100mA 2.496 2.494 200mA 2.492 2.498 2.496 2.494 2.492 4 5 6 8 7 9 10 INPUT VOLTAGE – V OUTPUT CHANGE – % GROUND CURRENT – mA 2.0 1.0 0.5 0 100 150 200 OUTPUT LOAD – mA 250 0 2 4 6 8 10 INPUT VOLTAGE – Volts 12 TPC 3. Ground Current vs. Supply Voltage 3.5 0 VIN = 6V 3.0 200mA 0.4 0.3 0.2 300mA 0.1 0.0 –0.1 –0.4 –50 300 TPC 4. Ground Current vs. Load Current 300 0.6 0.5 –0.2 –0.3 50 150 250 200 100 OUTPUT LOAD – mA 1.0 0.9 0.8 0.7 VIN = 6V 0 50 TPC 2. Output Voltage vs. Load Current 2.5 1.5 40 0 0 TPC 1. Line Regulation Output Voltage vs. Supply Voltage IL = 0 60 2.488 12 11 GROUND CURRENT – mA 3 80 20 2.490 2.488 VOUT = 2.5V 100 300mA 2.490 IL = 100A 120 GROUND CURRENT – A 2.500 OUTPUT VOLTAGE – V OUTPUT VOLTAGE – V 2.500 140 VIN = 6V VOUT = 2.5V IL = 300mA 2.5 IL = 200mA IL = 100mA 2.0 1.5 1.0 0.5 IL = 0mA 0 –25 0 25 50 75 100 JUNCTION TEMPERATURE – C 0 –50 125 –25 0 25 50 75 100 125 JUNCTION TEMPERATURE – C TPC 6. Ground Current vs. Junction Temperature TPC 5. Output Voltage Variation % vs. Junction Temperature 0.10 0.08 0.06 0.04 0.02 0 0 50 100 150 200 OUTPUT LOAD – mA 250 TPC 7. Dropout Voltage vs. Output Current 300 VOUT = 2.5V SD = VIN RL = 8.3 3.0 2.5 2.0 3 COUT = 1F 2 COUT = 10F 1 0 1.5 VIN – V 0.12 VOUT – V 0.14 INPUT/OUTPUT VOLTAGE – V INPUT/OUTPUT VOLTAGE – mV 0.16 1.0 0.5 4 2 VOUT = 2.5V SD = VIN RL = 8.3 0 0 1 2 3 TIME – Sec 4 TPC 8. Power-Up/Power-Down –4– 200 400 600 TIME – s 800 TPC 9. Power-Up Response REV. 0 ADP3333 2.50 3.00 40 80 140 TIME – s 2.5 2.49 2.4 mA 10 80 140 TIME – s 180 200 TPC 11. Line Transient Response 400 600 TIME – s 800 TPC 12. Load Transient Response 3 1F Volts 2.6 3.00 40 VIN = 4V VOUT = 2.5V CL = 10F 2.7 3.50 180 TPC 10. Line Transient Response Volts 2.6 2.50 300 3.50 VIN – V VIN – V 2.49 Volts 2.51 VIN = 4V VOUT = 2.5V CL = 1F 2.7 2.5 2.5 2.4 0 1 10F 0 3 1F VIN = 6V 2 A 300 10F 2 VOUT VOUT – V 2.51 VOUT = 2.5V RL = 8.3 CL = 10F 2.52 VOUT – V VOUT = 2.5V RL = 8.3 CL = 1F 2.52 2 VSD mA 1 10 0 VIN = 6V VOUT = 2.5V RL = 8.3 0 VIN = 6V 200 400 TIME – s 600 800 200 TPC 13. Load Transient Response 100 –40 100 CL = 1F IL = 50A –50 –60 VOLTAGE NOISE SPECTRAL DENSITY – V/ Hz CL = 1F IL = 500mA CL = 10F IL = 500mA 80 60 300mA 40 –70 0mA 20 0 –90 10 100 1k 10k 100k FREQUENCY – Hz 1M 10M TPC 16. Power Supply Ripple Rejection REV. 0 800 VOUT = 2.5V IL = 1mA CL = 10F 10 CL = 1F 1 0.1 0.01 CL = 10F IL = 50A –80 400 600 TIME – s TPC 15. Turn ON-Turn OFF Response 120 VOUT = 2.2V –30 RIPPLE REJECTION – dB 200 800 TPC 14. Short Circuit Current RMS NOISE – V –20 400 600 TIME – s 0 10 20 30 CL – F 40 TPC 17. RMS Noise vs. CL (10 Hz–100 kHz) –5– 50 0.001 10 100 1k 10k 100k FREQUENCY – Hz 1M TPC 18. Output Noise Density ADP3333 designing with LDOs more difficult because of their unclear specifications and extreme variations over temperature. THEORY OF OPERATION The new anyCAP LDO ADP3333 uses a single control loop for regulation and reference functions see (Figure 2). The output voltage is sensed by a resistive voltage divider consisting of R1 and R2 which is varied to provide the available output voltage option. Feedback is taken from this network by way of a series diode (D1) and a second resistor divider (R3 and R4) to the input of an amplifier. With the ADP3333 anyCAP LDO, this is no longer true. It can be used with virtually any good quality capacitor, with no constraint on the minimum ESR. This innovative design allows the circuit to be stable with just a small 1 µF capacitor on the output. Additional advantages of the pole splitting scheme include superior line noise rejection and very high regulator gain which leads to excellent line and load regulation. An impressive ±1.8% accuracy is guaranteed over line, load and temperature. OUTPUT INPUT ATTENUATION (VBANDGAP /V OUT) Q1 COMPENSATION CAPACITOR NONINVERTING WIDEBAND DRIVER gm R3 PTAT VOS CLOAD D1 FB R4 ADP3333 Additional features of the circuit include current limit and thermal shutdown. R1 (a) PTAT CURRENT APPLICATION INFORMATION RLOAD Capacitor Selection Output Capacitor R2 The stability and transient response of the LDO is a function of the output capacitor. The ADP3333 is stable with a wide range of capacitor values, types and ESR (anyCAP). A capacitor as low as 1.0 µF is all that is needed for stability; larger capacitors can be used if high current surges on the output are anticipated. The ADP3333 is stable with extremely low ESR capacitors (ESR » 0), such as Multilayer Ceramic Capacitors (MLCC) or OSCON. Note that the effective capacitance of some capacitor types fall below the minimum over temperature or with dc voltage. Ensure that the capacitor provides at least 1.0 µF of capacitance over temperature and dc bias. GND Figure 2. Functional Block Diagram A very high gain error amplifier is used to control this loop. The amplifier is constructed in such a way that at equilibrium it produces a large, temperature-proportional input “offset voltage” that is repeatable and very well controlled. The temperature proportional offset voltage is combined with the complementary diode voltage to form a “virtual bandgap” voltage, implicit in the network, although it never appears explicitly in the circuit. Ultimately, this patented design makes it possible to control the loop with only one amplifier. This technique also improves the noise characteristics of the amplifier by providing more flexibility on the trade-off of noise sources that leads to a low noise design. Input Bypass Capacitor An input bypass capacitor is not strictly required but it is recommended in any application involving long input wires or high source impedance. Connecting a 1.0 µF capacitor from the input to ground reduces the circuit's sensitivity to PC board layout and input transients. If a larger output capacitor is necessary then a larger value input capacitor is also recommended. The R1, R2 divider is chosen in the same ratio as the bandgap voltage to the output voltage. Although the R1, R2 resistor divider is loaded by the diode D1 and a second divider consisting of R3 and R4, the values can be chosen to produce a temperature stable output. This unique arrangement specifically corrects for the loading of the divider so that the error resulting from base current loading in conventional circuits is avoided. Output Current Limit The ADP3333 is short circuit protected by limiting the pass transistor’s base drive current. The maximum output current is limited to about 1 A. See TPC 14. Thermal Overload Protection The patented amplifier controls a new and unique noninverting driver that drives the pass transistor, Q1. The use of this special noninverting driver enables the frequency compensation to include the load capacitor in a pole splitting arrangement to achieve reduced sensitivity to the value, type and ESR of the load capacitance. The ADP3333 is protected against damage due to excessive power dissipation by its thermal overload protection circuit. Thermal protection limits the die temperature to a maximum of 165°C. Under extreme conditions (i.e., high ambient temperature and power dissipation) where the die temperature starts to rise above 165°C, the output current will be reduced until the die temperature has dropped to a safe level. Most LDOs place very strict requirements on the range of ESR values for the output capacitor because they are difficult to stabilize due to the uncertainty of load capacitance and resistance. Moreover, the ESR value, required to keep conventional LDOs stable, changes depending on load and temperature. These ESR limitations make Current and thermal limit protections are intended to protect the device against accidental overload conditions. For normal operation, the device's power dissipation should be externally limited so that the junction temperature will not exceed 125°C. –6– REV. 0 ADP3333 Calculating Junction Temperature Printed Circuit Board Layout Considerations Device power dissipation is calculated as follows: Use the following general guidelines when designing printed circuit boards: 1. Keep the output capacitor as close to the output and ground pins as possible. 2. Keep the input capacitor as close to the input and ground pins as possible. 3. PC board traces with larger cross sectional areas will remove more heat from the ADP3333. For optimum heat transfer, specify thick copper and use wide traces. 4. Connect the NC pins (Pins 5, 6, and 8) to ground for better thermal performance. 5. The thermal resistance can be decreased by approximately 10% by adding a few square centimeters of copper area to the lands connected to the pins of the LDO. 6. Use additional copper layers or planes to reduce the thermal resistance. Again, connecting the other layers to the ground and NC pins of the ADP3333 is best, but not necessary. When connecting the ground pad to other layers use multiple vias. PD = (VIN − VOUT ) I LOAD + (VIN ) IGND Where ILOAD and IGND are load current and ground current, VIN and VOUT are the input and output voltages respectively. Assuming the worst-case operating conditions are ILOAD = 300 mA, IGND = 2.6 mA, VIN = 4.0 V and VOUT = 3.0 V, the device power dissipation is: PD = (4.0 V − 3.0 V ) 300 mA + (4.2 V ) 2.0 mA = 308 mW The package used on the ADP3333 has a thermal resistance of 158°C/W for 4-layer boards. The junction temperature rise above ambient will be approximately equal to: T JA = 0.308 W × 158°C / W = 48.7°C So, to limit the junction temperature to 125°C, the maximum allowable ambient temperature is: T A( MAX ) = 125°C − 48.7°C = 76.3°C Shutdown Mode Applying a high signal to the shutdown pin, or connecting it to the input pin, will turn the output ON. Pulling the shutdown pin to 0.3 V or below, or connecting it to ground, will turn the output OFF. In shutdown mode, the quiescent current is reduced to less than 1 µA. REV. 0 –7– ADP3333 OUTLINE DIMENSIONS Dimensions shown in inches and (mm). C02615–1.5–7/01(0) 8-Lead Mini/micro SOIC Package [Mini_SO] (RM-8) 0.122 (3.10) 0.114 (2.90) 8 5 0.199 (5.05) 0.187 (4.75) 0.122 (3.10) 0.114 (2.90) 1 4 PIN 1 0.0256 (0.65) BSC 0.120 (3.05) 0.112 (2.84) 0.120 (3.05) 0.112 (2.84) 0.018 (0.46) SEATING 0.008 (0.20) PLANE 0.043 (1.09) 0.037 (0.94) 0.011 (0.28) 0.003 (0.08) 33 27 0.028 (0.71) 0.016 (0.41) PRINTED IN U.S.A. 0.006 (0.15) 0.002 (0.05) –8– REV. 0