ADP3000AR

a FEATURES Operates at Supply Voltages from 2 V to 30 V Works in Step-Up or Step-Down Mode Very Few External Components Required High Frequency Operation Up to 400 kHz Low Battery Detector on Chip User Adjustable Current Limit Fixed and Adjustable Output Voltage 8-Pin DIP and SO-8 Package Small Inductors and Capacitors APPLICATIONS Notebook, Palmtop Computers Cellular Telephones Hard Disk Drives Portable Instruments Pagers Micropower Step-Up/Step-Down Fixed 3.3 V, 5 V, 12 V and Adjustable High Frequency Switching Regulator ADP3000 FUNCTIONAL BLOCK DIAGRAM SET VIN A1 GAIN BLOCK/ ERROR AMP 1.245V REFERENCE 400kHz OSCILLATOR DRIVER COMPARATOR A0 ILIM SW1 SW2 ADP3000 R1 GND R2 SENSE 6.8µH IN5817 3.3V @ 180mA GENERAL DESCRIPTION VIN 2V–3.2V The ADP3000 is a versatile step-up/step-down switching regulator that operates from an input supply voltage of 2 V to 12 V in step-up mode and up to 30 V in step-down mode. The ADP3000 operates in Pulse Frequency Mode (PFM) and consumes only 500 µA, making it highly suitable for applications that require low quiescent current. The ADP3000 can deliver an output current of 100 mA at 3 V from a 5 V input in step-down configuration and 180 mA at 3.3 V from a 2 V input in step-up configuration. The auxiliary gain amplifier can be used as a low battery detector, linear regulator undervoltage lockout or error amplifier. The ADP3000 operates at 400 kHz switching frequency. This allows the use of small external components (inductors and capacitors), making the device very suitable for space constrained designs. VIN 5V–6V 100µF 10V 120Ω 1 ILIM 2 VIN SW1 3 ADP3000-3.3V FB 8 (SENSE) GND 5 SW2 4 C1, C2: AVX TPS D107 M010R0100 L1: SUMIDA CD43-6R8 + C1 100µF 10V Figure 1. Typical Application C1 100µF 10V RLIM 120Ω 1 ILIM 2 VIN 3 SW1 FB 8 ADP3000 SW2 4 GND 5 D1 1N5818 C1, C2: AVX TPS D107 M010R0100 L1: SUMIDA CD43-100 L1 10µH R2 150kΩ 1% R1 110kΩ 1% VOUT 3V 100mA CL + 100µF 10V Figure 2. Step-Down Mode Operation R EV. 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 which 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: 617/329-4700 World Wide Web Site: http://www.analog.com Fax: 617/326-8703 © Analog Devices, Inc., 1997 ADP3000–SPECIFICATIONS (0 C ≤ T ≤ +70 C, V A IN = 3 V unless otherwise noted)* Symbol VIN IQ 1.20 3.135 4.75 11.40 Min 2.0 500 1.245 3.3 5.00 12.00 8 32 32 75 fOSC 350 65 1.5 400 80 2 0.5 0.8 1.1 160 200 0.15 0.02 0.2 AV ISINK ILIM 1000 6000 300 400 –0.3 2.55 0.75 1.1 1.5 330 400 0.4 0.15 0.6 1.30 3.465 5.25 12.60 12.5 50 50 120 450 ADP3000 Typ Max 12.6 30.0 Units V V µA V V V V mV mV mV mV kHz % µs V V V nA nA V %/V %/V V/V µA mA %/°C 10 µA Parameter INPUT VOLTAGE SHUTDOWN QUIESCENT CURRENT COMPARATOR TRIP POINT VOLTAGE OUTPUT SENSE VOLTAGE Conditions Step-Up Mode Step-Down Mode VFB > 1.43 V; VSENSE > 1.1 × VOUT ADP3000 1 ADP3000-3.32 ADP3000-52 ADP3000-122 ADP3000 ADP3000-3.3 ADP3000-5 ADP3000-12 VOUT COMPARATOR HYSTERESIS OUTPUT HYSTERESIS OSCILLATOR FREQUENCY DUTY CYCLE SWITCH ON TIME SWITCH SATURATION VOLTAGE STEP-UP MODE STEP-DOWN MODE FEEDBACK PIN BIAS CURRENT SET PIN BIAS CURRENT GAIN BLOCK OUTPUT LOW REFERENCE LINE REGULATION GAIN BLOCK GAIN GAIN BLOCK CURRENT SINK CURRENT LIMIT CURRENT LIMIT TEMPERATURE COEFFICIENT SWITCH OFF LEAKAGE CURRENT MAXIMUM EXCURSION BELOW GND Measured at SW1 Pin VSW1 = 12 V, TA = +25°C TA = +25°C ISW1 ≤ 10 µA, Switch Off VFB > VREF ILIM Tied to VIN, VFB = 0 TA = +25°C VIN = 3.0 V, ISW = 650 mA VIN = 5.0 V, ISW = 1 A VIN = 12 V, ISW = 650 mA ADP3000 VFB = 0 V VSET = VREF ISINK = 300 µA VSET = 1.00 V 5 V ≤ VIN ≤ 30 V 2 V ≤ VIN ≤ 5 V RL = 100 kΩ3 VSET ≤ 1 V 220 Ω from ILIM to VIN D tON VSAT IFB ISET VOL 1 –400 –350 mV NOTES 1 This specification guarantees that both the high and low trip point of the comparator fall within the 1.20 V to 1.30 V range. 2 The output voltage waveform will exhibit a sawtooth shape due to the comparator hysteresis. The output voltage on the fixed output versions will always be within the specified range. 3 100 kΩ resistor connected between a 5 V source and the AO pin. *All limits at temperature extremes are guaranteed via correlation using standard statistical methods. Specifications subject to change without notice. – 2– REV. 0 ADP3000 PIN DESCRIPTIONS ABSOLUTE MAXIMUM RATINGS Mnemonic ILIM VIN SW1 SW2 GND AO SET FB/SENSE Function For normal conditions this pin is connected to VIN. When lower current is required, a resistor should be connected between ILIM and VIN. Limiting the switch current to 400 mA is achieved by connecting a 220 Ω resistor. Input Voltage. Collector of power transistor. For step-down configuration, connect to VIN. For step-up configuration, connect to an inductor/diode. Emitter of power transistor. For step-down configuration, connect to inductor/diode. For step-up configuration, connect to ground. Do not allow this pin to go more than a diode drop below ground. Ground. Auxiliary Gain (GB) output. The open collector can sink 300 µA. It can be left open if not used. SET Gain amplifier input. The amplifier’s positive input is connected to SET pin and its negative input is connected to 1.245 V. It can be left open if not used. On the ADP3000 (adjustable) version, this pin is connected to the comparator input. On the ADP3000-3.3, ADP3000-5 and ADP3000-12, the pin goes directly to the internal resistor divider that sets the output voltage. Input Supply Voltage, Step-Up Mode . . . . . . . . . . . . . . . 15 V Input Supply Voltage, Step-Down Mode . . . . . . . . . . . . . 36 V SW1 Pin Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 V SW2 Pin Voltage . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to VIN Feedback Pin Voltage (ADP3000) . . . . . . . . . . . . . . . . . .5.5 V Switch Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.5 A Maximum Power Dissipation . . . . . . . . . . . . . . . . . . 500 mW Operating Temperature Range . . . . . . . . . . . . . 0°C to +70°C Storage Temperature Range . . . . . . . . . . . . –65°C to +150°C Lead Temperature (Soldering, 10 sec) . . . . . . . . . . . . +300°C Thermal Impedance SO-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170°C/W N-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120°C/W PIN CONFIGURATIONS 8-Lead Plastic DIP 8-Lead SOIC (N-8) (SO-8) ILIM 1 VIN 2 8 FB (SENSE)* ILIM 1 VIN 2 8 FB (SENSE)* ADP3000 7 SET TOP VIEW SW1 3 (Not to Scale) 6 AO SW2 4 5 GND 7 SET TOP VIEW SW1 3 (Not to Scale) 6 AO SW2 4 5 GND ADP3000 * FIXED VERSIONS * FIXED VERSIONS ORDERING GUIDE Model ADP3000AN-3.3 ADP3000AR-3.3 ADP3000AN-5 ADP3000AR-5 ADP3000AN-12 ADP3000AR-12 ADP3000AN ADP3000AR Output Voltage 3.3 V 3.3 V 5V 5V 12 V 12 V Adjustable Adjustable Package Option N-8 SO-8 N-8 SO-8 N-8 SO-8 N-8 SO-8 N = plastic DIP, SO = small outline package. SET SET VIN A2 GAIN BLOCK/ ERROR AMP 1.245V REFERENCE A0 ILIM SW1 1.245V REFERENCE VIN A1 GAIN BLOCK/ ERROR AMP A0 ILIM SW1 A1 OSCILLATOR DRIVER SW2 OSCILLATOR DRIVER COMPARATOR SW2 COMPARATOR ADP3000 R1 R2 SENSE ADP3000 GND GND FB Figure 3a. Functional Block Diagram for Adjustable Version Figure 3b. Functional Block Diagram for Fixed Version 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 ADP3000 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. WARNING! ESD SENSITIVE DEVICE REV. 0 –3– ADP3000–Typical Characteristics 2.5 1.4 1.2 1.0 VIN = 5V @ TA = +25°C 1400 1200 QUIESCENT CURRENT – µA 2.0 ON VOLTAGE – V 1000 800 600 400 200 0 1.5 QUIESCENT CURRENT @ TA = +25°C 1.5 VCE(SAT) – V VIN = 5V @ TA = +25°C 0.8 0.6 0.4 0.2 0.0 0.1 VIN = 12V @ TA = +25°C 1.0 VIN = 3V @ TA = +25°C VIN = 2V @ TA = +25°C 0 0.1 0.2 0.4 0.6 0.8 1.0 1.2 SWITCH CURRENT – A 1.4 1.5 0.5 0.2 0.3 0.4 0.5 0.6 SWITCH CURRENT – A 0.8 0.9 3 6 9 12 15 18 21 24 27 INPUT VOLTAGE – V 30 Figure 4. Switch ON Voltage vs. Switch Current in Step-Up Mode Figure 5. Saturation Voltage vs. Switch Current in Step-Down Mode Figure 6. Quiescent Current vs. Input Voltage 406 OSCILLATOR FREQUENCY – kHz 405 404 403 402 401 400 399 396 2 4 6 8 10 12 15 18 21 24 27 30 INPUT VOLTAGE – V OSCILLATOR FREQUENCY – @ TA = +25°C SWITCH CURRENT – A 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 1 VIN = 5V TA = 0°C 1.8 1.6 SWITCH CURRENT – A 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 1 VIN = 12V TA = +25°C TA = 0°C TA = +25°C TA = +85°C TA = +85°C 10 RLIM – Ω 100 1k 10 RLIM – Ω 100 1k Figure 7. Oscillator Frequency vs. Input Voltage Figure 8a. Maximum Switch Current vs. RLIM in Step-Down Mode (5 V) Figure 8b. Maximum Switch Current vs. RLIM in Step-Down Mode (12 V) 1.8 1.6 SWITCH CURRENT – A 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 1 VIN = 3V OSCILLATOR FREQUENCY – kHz 440 430 420 410 400 390 380 370 360 350 340 10 RLIM – Ω 100 1k ON TIME – µs 2.30 2.25 2.20 2.15 2.10 2.05 2.00 1.95 1.90 1.85 25 70 0 TEMPERATURE – °C (TA) 85 1.80 –40 25 70 0 TEMPERATURE – °C (TA) 85 TA = +25°C TA = 0°C TA = +85°C 330 –40 Figure 8c. Maximum Switch Current vs. RLIM in Step-Up Mode (3 V) Figure 9. Oscillator Frequency vs. Temperature Figure 10. Switch ON Time vs. Temperature –4– REV. 0 ADP3000 100 90 80 DUTY CYCLE – % 0.56 0.54 1.25 1.20 VIN = 12V @ ISW = 0.65A ON VOLTAGE – V SATURATION VOLTAGE – V 70 60 50 40 30 20 10 0 –40 25 70 0 TEMPERATURE – °C (TA) 85 0.52 0.50 0.48 VIN = 3V @ ISW = 0.65A 0.46 0.44 0.42 –40 1.15 1.10 1.05 1.00 0.95 0.90 –40 25 70 0 TEMPERATURE – °C (TA) 85 0 25 70 85 TEMPERATURE – °C (TA) Figure 11. Duty Cycle vs. Temperature Figure 12. Saturation Voltage vs. Temperature in Step-Up Mode Figure 13. Switch ON Voltage vs. Temperature in Step-Down Mode 250 700 VIN = 20V 600 QUIESCENT CURRENT – µA 350 300 BIAS CURRENT – µA 0 25 70 TEMPERATURE – °C (TA) 85 250 200 150 100 50 0 –40 200 BIAS CURRENT – µA 500 400 300 200 100 150 100 50 0 –40 25 70 0 TEMPERATURE – °C (TA) 85 0 –40 0 25 70 TEMPERATURE – °C (TA) 85 Figure 14. Feedback Bias Current vs. Temperature Figure 15. Quiescent Current vs. Temperature Figure 16. Set Pin Bias Current vs. Temperature REV. 0 –5– ADP3000 THEORY OF OPERATION APPLICATIONS INFORMATION COMPONENT SELECTION Inductor Selection The ADP3000 is a versatile, high frequency, switch mode power supply (SMPS) controller. The regulated output voltage can be greater than the input voltage (boost or step-up mode) or less than the input (buck or step-down mode). This device uses a gated oscillator technique to provide high performance with low quiescent current. A functional block diagram of the ADP3000 is shown in Figure 3a. The internal 1.245 V reference is connected to one input of the comparator, while the other input is externally connected (via the FB pin) to a resistor divider connected to the regulated output. When the voltage at the FB pin falls below 1.245 V, the 400 kHz oscillator turns on. A driver amplifier provides base drive to the internal power switch and the switching action raises the output voltage. When the voltage at the FB pin exceeds 1.245 V, the oscillator is shut off. While the oscillator is off, the ADP3000 quiescent current is only 500 µA. The comparator’s hysteresis ensures loop stability without requiring external components for frequency compensation. The maximum current in the internal power switch can be set by connecting a resistor between VIN and the ILIM pin. When the maximum current is exceeded, the switch is turned OFF. The current limit circuitry has a time delay of about 0.3 µs. If an external resistor is not used, connect ILIM to VIN. This yields the maximum feasible current limit. Further information on ILIM is included in the “Applications” section of this data sheet. The ADP3000 internal oscillator provides typically 1.7 µs ON and 0.8 µs OFF times. An uncommitted gain block on the ADP3000 can be connected as a low battery detector. The inverting input of the gain block is internally connected to the 1.245 V reference. The noninverting input is available at the SET pin. A resistor divider, connected between VIN and GND with the junction connected to the SET pin, causes the AO output to go LOW when the low battery set point is exceeded. The AO output is an open collector NPN transistor that can sink in excess of 300 µA. The ADP3000 provides external connections for both the collector and emitter of its internal power switch, which permits both step-up and step-down modes of operation. For the stepup mode, the emitter (Pin SW2) is connected to GND and the collector (Pin SW1) drives the inductor. For step-down mode, the emitter drives the inductor while the collector is connected to VIN. The output voltage of the ADP3000 is set with two external resistors. Three fixed voltage models are also available: ADP3000–3.3 (+3.3 V), ADP3000–5 (+5 V) and ADP3000–12 (+12 V). The fixed voltage models include laser-trimmed voltage-setting resistors on the chip. On the fixed voltage models of the ADP3000, simply connect the feedback pin (Pin 8) directly to the output voltage. For most applications the inductor used with the ADP3000 will fall in the range between 4.7 µH to 33 µH. Table I shows recommended inductors and their vendors. When selecting an inductor, it is very important to make sure that the inductor used with the ADP3000 is able to handle a current that is higher than the ADP3000’s current limit without saturation. As a rule of thumb, powdered iron cores saturate softly, whereas Ferrite cores saturate abruptly. Rod or “open” drum core geometry inductors saturate gradually. Inductors that saturate gradually are easier to use. Even though rod or drum core inductors are attractive in both price and physical size, these types of inductors must be handled with care because they have high magnetic radiation. Toroid or “closed” core geometry should be used when minimizing EMI is critical. In addition, inductor dc resistance causes power loss. It is best to use low dc resistance inductors so that power loss in the inductor is kept to the minimum. Typically, it is best to use an inductor with a dc resistance lower than 0.2 Ω. Table I. Recommended Inductors Vendor Coiltronics Coiltronics Sumida Sumida Series OCTAPAC UNIPAC Core Type Toroid Open Phone Numbers (407) 241-7876 (407) 241-7876 (847) 956-0666 (847) 956-0666 CD43, CD54 Open CDRH62, CDRH73, Semi-Closed CDRH64 Geometry Capacitor Selection For most applications, the capacitor used with the ADP3000 will fall in the range between 33 µF to 220 µF. Table II shows recommended capacitors and their vendors. For input and output capacitors, use low ESR type capacitors for best efficiency and lowest ripple. Recommended capacitors include AVX TPS series, Sprague 595D series, Panasonic HFQ series and Sanyo OS-CON series. When selecting a capacitor, it is important to make sure the maximum capacitor ripple current rms rating is higher than the ADP3000’s rms switching current. It is best to protect the input capacitor from high turn-on current charging surges by derating the capacitor voltage by 2:1. For very low input or output voltage ripple requirements, Sanyo OS-CON series capacitors can be used since this type of capacitor has very low ESR. Alternatively, two or more tantalum capacitors can be used in parallel. –6– REV. 0 ADP3000 Table II. Recommended Capacitors Vendor AVX Sanyo Sprague Panasonic Series TPS OS-CON 595D HFQ Type Surface Mount Through-Hole Surface Mount Through-Hole Phone Numbers (803) 448-9411 (619) 661-6835 (603) 224-1961 (201) 348-5200 The delay through the current limiting circuit is approximately 0.3 µs. If the switch ON time is reduced to less than 1.7 µs, accuracy of the current trip-point is reduced. Attempting to program a switch ON time of 0.3 µs or less will produce spurious responses in the switch ON time. However, the ADP3000 will still provide a properly regulated output voltage. PROGRAMMING THE GAIN BLOCK DIODE SELECTION The ADP3000’s high switching speed demands the use of Schottky diodes. Suitable choices include the 1N5817, 1N5818, 1N5819, MBRS120LT3 and MBR0520LT1. Do not use fast recovery diodes because their high forward drop lowers efficiency. Neither general-purpose diodes nor small signal diodes should be used. PROGRAMMING THE SWITCHING CURRENT LIMIT OF THE POWER SWITCH The gain block of the ADP3000 can be used as a low battery detector, error amplifier or linear post regulator. The gain block consists of an op amp with PNP inputs and an open-collector NPN output. The inverting input is internally connected to the ADP3000’s 1.245 V reference, while the noninverting input is available at the SET pin. The NPN output transistor will sink in excess of 300 µA. Figure 18 shows the gain block configured as a low battery monitor. Resistors R1 and R2 should be set to high values to reduce quiescent current, but not so high that bias current in the SET input causes large errors. A value of 33 kΩ for R2 is a good compromise. The value for R1 is then calculated from the formula: R1 = V LOBATT – 1.245 V 1.245 V R2 The ADP3000’s RLIM pin permits the cycle by cycle switch current limit to be programmed with a single external resistor. This feature offers major advantages which ultimately decrease the component cost and P.C.B. real estate. First, it allows the ADP3000 to use low value, low saturation current and physically small inductors. Additionally, it allows the ADP3000 to use a physically small surface mount tantalum capacitor with a typical ESR of 0.1 Ω to achieve an output ripple as low as 40 mV to 80 mV, as well as low input ripple. As a rule of thumb, the current limit is usually set to approximately 3 to 5 times the full load current for boost applications and about 1.5–3 times of the full load current in buck applications. The internal structure of the ILIM circuit is shown in Figure 17. Q1 is the ADP3000’s internal power switch, which is paralleled by sense transistor Q2. The relative sizes of Q1 and Q2 are scaled so that IQ2 is 0.5% of IQ1. Current flows to Q2 through both an internal 80 Ω resistor and the RLIM resistor. The voltage on these two resistors biases the base-emitter junction of the oscillator-disable transistor, Q3. When the voltage across R1 and RLIM exceeds 0.6 V, Q3 turns on and terminates the output pulse. If only the 80 Ω internal resistor is used (i.e. the ILIM pin is connected directly to VIN), the maximum switch current will be 1.5 A. Figure 8a gives values for lower current-limit values. RLIM (EXTERNAL) VIN VIN ILIM R1 Q3 80Ω (INTERNAL) IQ1 DRIVER 400kHz OSC 200 Q2 where VLOBATT is the desired low battery trip point. Since the gain block output is an open-collector NPN, a pull-up resistor should be connected to the positive logic power supply. 5V RL 47k Ω ADP3000 VBATT R1 1.245V REF SET R2 33k Ω GND VIN AO TO PROCESSOR 1.6MΩ RHYS VLB – 1.245V R1 = 37.7µA VLB = BATTERY TRIP POINT Figure 18. Setting the Low Battery Detector Trip Point ADP3000 SW1 Q1 POWER SWITCH SW2 Figure 17. ADP3000 Current Limit Operation REV. 0 –7– ADP3000 The circuit of Figure 18 may produce multiple pulses when approaching the trip point due to noise coupled into the SET input. To prevent multiple interrupts to the digital logic, hysteresis can be added to the circuit (Figure 18). Resistor RHYS, with a value of 1 MΩ to 10 MΩ, provides the hysteresis. The addition of RHYS will change the trip point slightly, so the new value for R1 will be: R1 = V LOBATT –1.245 V 1.245 V  V L − 1.245 V   R2  −  R + R    L HYS  Step-Down  P D =  I SW VCESAT   1   VO  1 + β   V – V     IN CE ( SAT )    2 IO    + IQ VIN   I SW   [ ][ ] where: ISW is ILIMIT in the case of current limit is programmed externally or maximum inductor current in the case of current limit is not programmed eternally. VCE(SAT) = Check this value by applying ISW to Figure 8b. 1.2 V is typical value. D = 0.75 (Typical Duty Ratio for a Single Switching Cycle). VO = Output Voltage. IO = Output Current. VIN = Input Voltage. IQ = 500 µA (Typical Shutdown Quiescent Current). β = 30 (Typical Forced Beta). The temperature rise can be calculated from: ∆T = P D × θ JA where VL is the logic power supply voltage, RL is the pull-up resistor, and RHYS creates the hysteresis. POWER TRANSISTOR PROTECTION DIODE IN STEPDOWN CONFIGURATION When operating the ADP3000 in the step-down mode, the output voltage is impressed across the internal power switch’s emitter-base junction when the switch is off. In order to protect the switch, a Schottky diode must be placed in a series with SW2 when the output voltage is set to higher than 6 V. Figure 19 shows the proper way to place the protection diode, D2. The selection of this diode is identical to the step-down commuting diode (see Diode Selection section for information). VIN C2 + R3 1 ILIM 2 VIN 3 SW1 FB 8 D2 D1 L1 C1 + VOUT > 6V D1, D2 = 1N5818 SCHOTTKY DIODES where: ∆T = Temperature Rise. PD = Device Power Dissipation. θJA = Thermal Resistance (Junction-to-Ambient). As example, consider a boost converter with the following specifications: VIN = 2 V, IO = 180 mA, VO = 3.3 V. ISW = 0.8 A (Externally Programmed). With Step-Up Power Dissipation Equation:   (2)(0.8)  2   (4) 0.18  0.75 1– + 500 E − 6 2 P D = 0.82 × 1 + 30  3.3   0.8       ADP3000 GND 5 SW2 4 R2 R1 [ ] [ ][ ] Figure 19. Step-Down Model VOUT > 6.0 V THERMAL CONSIDERATIONS = 185 mW Power dissipation internal to the ADP3000 can be approximated with the following equations. Step-Up  V I   V   4I  2 P D =  I SW R + IN SW  D 1– IN   O  + IQ V IN β   V O   I SW   Using the SO-8 Package: ∆T = 185 mW (170°C/W) = 31.5°C. Using the N-8 Package: ∆T = 185 mW (120°C/W) = 22.2°C. At a 70°C ambient, die temperature would be 101.45°C for SO-8 package and 92.2°C for N-8 package. These junction temperatures are well below the maximum recommended junction temperature of 125°C. Finally, the die temperature can be decreased up to 20% by using a large metal ground plate as ground pickup for the ADP3000. [ ][ ] where: ISW is ILIMIT in the case of current limit programmed externally, or maximum inductor current in the case of current limit not programmed externally. R = 1 Ω (Typical RCE(SAT)). D = 0.75 (Typical Duty Ratio for a Single Switching Cycle). VO = Output Voltage. IO = Output Current. VIN = Input Voltage. IQ = 500 µA (Typical Shutdown Quiescent Current). β = 30 (Typical Forced Beta) –8– REV. 0 ADP3000 Typical Application Circuits VIN 2V → 3.2V + C1 100µF 10V 120Ω 1 2 L1 6.8µH 1N5817 VOUT 3.3V 180mA VIN 4.5V → 5.5V L1 15µH + C1 100µF 10V 124Ω 1 2 1N5817 VOUT 12V 50mA ILIM VIN ILIM SW1 3 VIN SW1 3 ADP3000-3.3V GND 5 ADP3000-12V SENSE 8 + C2 100µF 10V GND 5 SENSE 8 SW2 4 SW2 4 + C2 100µF 16V L1 = SUMIDA CD43-6R8 C1, C2 = AVX TPS D107 M010R100 TYPICAL EFFICIENCY = 75% L1 = SUMIDA CD54-150 C1 = AVX TPS D107 M010R0100 C2 = AVX TPS E107 M016R0100 TYPICAL EFFICIENCY = 75% Figure 20. 2 V to 3.3 V/180 mA Step-Up Converter Figure 23. 4.5 V to 12 V/ 50 mA Step-Up Converter VIN 2V → 3.2V + C1 100µF 10V 120Ω 1 2 L1 6.8µH VIN 1N5817 VOUT 5V 100mA 5V → 6V C1 + 100µF 10V 120Ω 1 ILIM 2 3 FB 8 VIN SW1 L1 10µH R2 150kΩ C2 + 100µF 10V R1 110kΩ VOUT 3V 100mA ILIM VIN SW1 3 ADP3000-5V SENSE 8 GND 5 ADP3000-ADJ GND SW2 4 SW2 4 + C2 100µF 10V 5 L1 = SUMIDA CD43-100 C1, C2 = AVX TPS D107 M010R100 TYPICAL EFFICIENCY = 75% D1 IN5817 L1 = SUMIDA CD43-6R8 C1, C2 = AVX TPS D107 M010R0100 TYPICAL EFFICIENCY = 80% Figure 21. 2 V to 5 V/100 mA Step-Up Converter Figure 24. 5 V to 3 V/100 mA Step-Down Converter VIN 2.7V → 4.5V + C1 100µF 10V 120Ω 1 2 L1 6.8µH 1N5817 VOUT 5V 150mA VIN 10V → 13V C1 + 33µF 20V 250Ω 1 ILIM 2 3 ILIM VIN VIN SW1 SENSE 8 SW1 3 ADP3000-5V SENSE 8 GND 5 ADP3000-5V GND SW2 4 + C2 100µF 10V L1 10µH VOUT 5V 250mA SW2 4 5 L1 = SUMIDA CD43-100 C1 = AVX TPS D336 M020R0200 C2 = AVX TPS D107 M010R0100 TYPICAL EFFICIENCY = 77% D1 IN5817 + C2 100µF 10V L1 = SUMIDA CD43-6R8 C1, C2 = AVX TPS D107 M010R100 TYPICAL EFFICIENCY = 80% Figure 22. 2.7 V to 5 V/150 mA Step-Up Converter Figure 25. 10 V to 5 V/250 mA Step-Down Converter REV. 0 –9– ADP3000 VIN 5V C1 + 47µF 16V 240Ω 1 ILIM 2 VIN 3 SW1 SENSE 8 ADP3000-5V GND 5 D1 IN5817 L1 = SUMIDA CD53-150 C1 = AVX TPS D476 M016R0150 C2 = AVX TPS D107 M010R0100 TYPICAL EFFICIENCY = 60% SW2 4 L1 15µH C2 + 100µF 10V VOUT –5V 100mA Figure 26. 5 V to –5 V/100 mA Inverter 2.5V → 4.2V 100kΩ + – 100µF 10V AVX-TPS 120Ω ILIM SET 1MΩ 90kΩ VIN SW1 33nF 90kΩ 330kΩ 2N2907 (SUMIDA – CDRH62) 6.8µH IN5817 100kΩ 10kΩ 348kΩ 1% 200kΩ 1% + 100µF 10V – AVX-TPS IN1 IN2 VO1 1µF 6V (MLC) 1µF 6V (MLC) 3V 100mA 3V 100mA ADP3000 AO FB ADP3302AR1 SD GND VO2 GND SW2 Figure 27. 1 Cell LI-ION to 3 V/200 mA Converter with Shutdown at VIN ≤ 2.5 V 80 % EFFICIENCY AT VIN ≤ 2.5V IO = 50mA + 50mA SHDN IQ = 500µA 75 70 IO = 100mA + 100mA 65 VIN 2.6 3.0 3.4 3.8 4.2 (V) Figure 28. Typical Efficiency of the Circuit of Figure 27 –10– REV. 0 ADP3000 OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 8-Lead Plastic DIP (N-8) 8-Lead SOIC (SO-8) 0.430 (10.92) 0.348 (8.84) 8 5 0.1968 (5.00) 0.1890 (4.80) 8 1 5 4 0.280 (7.11) 0.240 (6.10) 1 4 0.1574 (4.00) 0.1497 (3.80) 0.325 (8.25) 0.300 (7.62) 0.2440 (6.20) 0.2284 (5.80) PIN 1 0.210 (5.33) MAX 0.160 (4.06) 0.115 (2.93) 0.060 (1.52) 0.015 (0.38) 0.130 (3.30) MIN SEATING PLANE PIN 1 0.195 (4.95) 0.115 (2.93) 0.0098 (0.25) 0.0040 (0.10) 0.0688 (1.75) 0.0532 (1.35) 0.0196 (0.50) x 45° 0.0099 (0.25) 0.022 (0.558) 0.100 0.070 (1.77) 0.014 (0.356) (2.54) 0.045 (1.15) BSC 0.015 (0.381) 0.008 (0.204) SEATING PLANE 0.0500 0.0192 (0.49) (1.27) 0.0138 (0.35) BSC 0.0098 (0.25) 0.0075 (0.19) 8° 0° 0.0500 (1.27) 0.0160 (0.41) REV. 0 –11– – 12– C2223–12–1/97 PRINTED IN U.S.A.