APW7079-28DI-TRL

APW7079 Low-Supply-Current Synchronous Step-up DC-DC Converter Features • • • • • • • • • 0.9V Typical Start-up Input Voltage 11µA Typical No Load Quiescent Current PFM Operation High Efficiency up to 92% Fixed 1.8V, 2.6V, 2.8V, 3V, 3.3V, 3.8V, 4.5V or 5V Output Voltage 600mA Internal Switch Current Internal Synchronous Rectifier SOT-89 Package Lead Free and Green Devices Available (RoHS Compliant) General Description The APW7079 is a compact, PFM mode, and step-up DC-DC converter with low quiescent current. The internal synchronous rectifier reduces cost and PCB space by eliminating the need for an external Schottky diode. Low on-resistance of the internal switches improves the efficiency up to 92%. The start-up voltage is guaranteed below 1V. After start-up, the device can operate with input voltage down to 0.7V. The APW7079 is suitable for portable battery-powered applications. Consuming only 11µA quiescent current and an optimized control scheme allows the device to operate at very high efficiency over the entire load current range. Efficiency vs. Output Current 100 Applications Efficiency (%) 90 80 • • • Toy Wireless Mouse Portable Instrument 70 60 50 40 30 VIN=1.2V VIN=1.5V APW7079-30 0.1 1 10 100 1000 VIN=0.9V VIN=1.0V VIN=2.4V Pin Configuration SOT89 20 10 0 Output Current, I OUT (mA) Simplified Application Circuit VOUT 2 (TAB) LX 3 G ND 1 VIN IIN L1 22µH C1 22µF APW7079 LX VOUT GND IOUT VOUT Top View C2 47µF ANPEC reserves the right to make changes to improve reliability or manufacturability without notice, and advise customers to obtain the latest version of relevant information to verify before placing orders. Copyright © ANPEC Electronics Corp. Rev. A.3 - Oct., 2008 1 www.anpec.com.tw APW7079 Ordering and Marking Information APW7079 Assembly Material Handling Code Temperature Range Package Code Voltage Code APW7079 XXXXX18 APW7079 XXXXX28 APW7079 XXXXX33 79 Package Code D : SOT-89 Operating Ambient Temperature Range I : -40 to 85oC Handling Code TR : Tape & Reel Assembly Material L : Lead Free Device G : Halogen and Lead Free Device Voltage Code 18: 1.8V 26: 2.6V 28: 2.8V 30: 3.0V 33: 3.3V 38: 3.8V 45: 4.5V 50: 5.0V APW7079-26DI: APW7079-28DI: APW7079-33DI: APW7079-50DI: APW7079 XXXXX26 APW7079 XXXXX30 APW7079 XXXXX38 APW7079 XXXXX50 XXXXX - Date Code, 26: 2.6V XXXXX - Date Code, 30: 3.0V XXXXX - Date Code, 38: 3.8V XXXXX - Date Code, 50: 5.0V APW7079-18DI: APW7079-28DI: APW7079-33DI: XXXXX - Date Code, 18: 1.8V XXXXX - Date Code, 28: 2.8V XXXXX - Date Code, 33: 3.3V XXXXX - Date Code, 45: 5.0V APW7079-45DI: APW7079 XXXXX45 Note: ANPEC lead-free products contain molding compounds/die attach materials and 100% matte tin plate termination finish; which are fully compliant with RoHS. ANPEC lead-free products meet or exceed the lead-free requirements of IPC/JEDEC J-STD-020C for MSL classification at lead-free peak reflow temperature. ANPEC defines “Green” to mean lead-free (RoHS compliant) and halogen free (Br or Cl does not exceed 900ppm by weight in homogeneous material and total of Br and Cl does not exceed 1500ppm by weight). Absolute Maximum Ratings (Note 1) Symbol VOUT VLX TSTG TSDR LX to GND Voltage Storage Temperature Maximum Lead Soldering Temperature, 10 Seconds Parameter Output Voltage (VOUT to GND) Rating -0.3 ~ 6 -0.3 ~ VOUT+1 -65 ~ 150 260 Unit V V ° C ° C Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Thermal Characteristics Symbol θJA Parameter Thermal Resistance -Junction to Ambient (Note 2) Typical Value SOT-89 180 Unit o C/W Note 2: θJA is measured with the component mounted on a high effective thermal conductivity test board in free air. Recommended Operating Conditions (Note 3, 4) Symbol VOUT VIN VLX IOUT TA TJ Converter Supply Voltage LX to GND Voltage Converter Output Current Ambient Temperature Junction Temperature Parameter Output Voltage (VOUT to GND) Range 0.7 ~ 5.5 0.3 ~ VOUT+1 -0.3 ~ VOUT+0.3 0 ~ 0.9 x IOUT(MAX) -40 ~ 85 -40 ~ 125 Unit V V V A °C °C Note 3: Refer to the typical application circuit Note 4: Refer to “Application Information” for detail value. C opyright © A NPEC Electronics Corp. Rev. A.3 - Oct., 2008 2 www.anpec.com.tw APW7079 Electrical Characteristics Refer to Typical Application Circuits. VIN=1.5V, RLOAD = ∞, and TA= -40 ~ 85oC, unless otherwise noted. Typical values are at TA=25oC. Symbol VIN Parameter Converter Supply Voltage Start-up Voltage RLOAD=3kΩ Test Conditions Min. 0.7 - APW7079 Typ. 0.9 1.8 2.6 2.8 3.0 3.3 3.8 4.5 5.0 11 0.9 4 0.5 0.4 0.4 0.4 0.4 0.4 0.3 0.3 1 0.8 0.8 0.7 0.6 0.5 0.4 0.4 600 150 40 Max. 5.5 1 1.836 2.652 2.856 3.06 3.366 3.876 4.59 5.1 15 1.2 5 85 700 1 1 - Unit V V APW7079-18 APW7079-26 APW7079-28 VOUT Output Voltage APW7079-30 APW7079-33 APW7079-38 APW7079-45 APW7079-50 IDD TOFF(MIN) TON(MAX) Supply Current Main Switch Min. Off-time Main Switch Max. On-time Main Switch Max. Duty APW7079-18 APW7079-26 APW7079-28 RN-FET Main Switch on Resistance ILX=100mA APW7079-30 APW7079-33 APW7079-38 APW7079-45 APW7079-50 APW7079-18 APW7079-26 APW7079-28 RP-FET Synchronous Switch on Resistance ILX=100mA APW7079-30 APW7079-33 APW7079-38 APW7079-45 APW7079-50 ILIM Main Switch Current Limit Main Switch Leakage Current Synchronous Switch Leakage Current Over Temperature Shutdown Over Temperature Hysteresis VOUT = VOUT(Typ.)+0.5V Measured at VOUT No Inductor Connected 1.764 2.548 2.744 2.94 3.234 3.724 4.41 4.9 7 0.6 3 75 500 - V µA µs µs % Ω Ω mA µA µA °C °C C opyright © A NPEC Electronics Corp. Rev. A.3 - Oct., 2008 3 www.anpec.com.tw APW7079 Typical Operating Characteristics (Refer to the application circuit in the section “Typical Application Circuit”, VIN=1.5V, L1=22µH, TA=25oC unless otherwise noted.) Efficiency vs. Output Current 100 90 1.84 1.82 Output Voltage vs. Output Current Output Voltage, VOUT (V) 80 70 1.80 1.78 1.76 1.74 1.72 1.70 1.68 1.66 VIN=0.9V VIN=1.0V VIN=1.2V VIN=1.5V APW7079-18 0 50 100 150 200 250 300 Efficiency (%) 60 50 40 30 20 10 0 0.1 VIN=0.9V VIN=1.0V VIN=1.2V VIN=1.5V APW7079-18 1.64 1 10 100 1000 Output Current, IOUT (mA) Output Current, IOUT (mA) Efficiency vs. Output Current 100 90 Output Voltage vs. Output Current 3.1 70 Output Voltage, VOUT (V) 80 3.0 Efficiency (%) 60 50 40 30 20 10 0 0.1 VIN=0.9V VIN=1.0V VIN=1.2V VIN=1.5V APW7079-30 VIN=2.4V 2.9 VIN=2.4V VIN=1.5V 2.8 VIN=1.2V VIN=1.0V VIN=0.9V APW7079-30 150 200 250 300 350 400 2.7 2.6 1 10 100 1000 0 50 100 Output Current, IOUT (mA) Output Current, IOUT (mA) Output Voltage vs. Output Current 100 90 6 5 Output Voltage vs. Output Current 70 Output Voltage, VOUT (V) 80 Efficiency (%) 4 3 2 1 0 60 50 40 30 20 10 0 0.1 1 10 100 1000 VIN=1.5V APW7079-50 VIN=0.9V VIN=1.0V VIN=1.2V VIN=2.4V VIN=3.6V VIN=3.6V VIN=0.9V VIN=1.0V VIN=1.2V APW7079-50 0 50 100 150 200 250 300 350 VIN=2.4V VIN=1.5V Output Current, IOUT (mA) C opyright © A NPEC Electronics Corp. Rev. A.3 - Oct., 2008 4 Output Current, IOUT (mA) www.anpec.com.tw APW7079 Typical Operating Characteristics (Cont.) (Refer to the application circuit in the section “Typical Application Circuit”, VIN=1.5V, L1=22µH, TA=25oC unless otherwise noted.) 1.4 Start-up/Hold-on Voltage vs. Output Current Start-up/Hold-on Voltage, VST /VHOLD (V) Start-up Start-up/Hold-on Voltage vs. Output Current 1.4 1.2 1 0.8 0.6 Hold-on 0.4 0.2 APW7079-30 0 0 10 20 30 40 50 Start-up Start-up/Hold-on Voltage, VST /VHOLD (V) 1.2 1 0.8 Hold-on 0.6 0.4 0.2 APW7079-18 0 0 10 20 30 40 50 Output Current, IOUT (mA) Output Current, IOUT (mA) 1.4 Start-up/Hold-on Voltage vs. Output Current No Load Battery Current, IIN (µA) Start-up Start-up/Hold-on Voltage, VST /VHOLD (V) 70 60 50 40 30 20 10 0 No Load Battery Current vs. Input Voltage 1.2 1 0.8 0.6 0.4 0.2 Hold-on APW7079-50 APW7079-50 0 0 10 20 30 40 50 APW7079-18 APW7079-30 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 Output Current, IOUT (mA) Input Voltage, VIN (V) 0.8 Main Switch ON Resistance vs. Junction Temperature Synchronous Switch ON Resistance, RP-FET (Ω ) 1.6 1.4 1.2 1.0 0.8 0.6 Synchronous Switch ON Resistance vs. Junction Temperature Main Switch ON Resistance, RN-FET (Ω ) 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 -50 -25 0 25 50 75 100 125 APW7079-18 APW7079-30 APW7079-50 APW7079-18 0.4 APW7079-30 0.2 0.0 -50 -25 0 25 50 75 100 125 APW7079-50 Junction Temperature, TJ (oC) C opyright © A NPEC Electronics Corp. Rev. A.3 - Oct., 2008 5 Junction Temperature, TJ (oC) www.anpec.com.tw APW7079 Operating Waveforms Load Transient Response Line Transient Response IOUT=10mA -> 110mA -> 10mA IOUT rise/fall time = 1µs VIN=1.5V IOUT 110mA VIN 1.5V 2V 2 10mA 3 VOUT 1 3 VOUT CH2: IOUT, 100mA/Div, DC CH3: VOUT, 50mV/Div, AC Time: 0.1ms/Div CH1: VIN, 0.5V/Div, DC CH3: VOUT, 50mV/Div, AC Time: 0.1ms/Div Heavy Load Switching Waveform IOUT=100mA, VIN=1.5V ILX 2 3 VOUT VLX 4 CH2: ILX, 200mA/Div, DC CH3: VOUT, 50mV/Div, AC CH4: VLX, 2V/Div, DC Time: 5µs/Div C opyright © A NPEC Electronics Corp. Rev. A.3 - Oct., 2008 6 www.anpec.com.tw APW7079 Pin Description PIN NO. 1 2 3 NAME LX VOUT GND Junction of N-FET and P-FET Drains. Connect the inductor here and minimize the trace area for lowest EMI. Converter output and control circuitry bias supply pin. Ground. FUNCTION Block Diagram VOUT 2 Zero Crossing Comparator + 0.9µs Min. off-time Error Comparator + VREF Control Logic Gate Driver Main Switch Thermal Shutdown Synchronous Switch LX 3 4µs Max. on-time Current Limit Comparator + Soft start 1 RSENSE GND Typical Application Circuit VIN IIN L1 22µH C1 22µF APW7079 LX VOUT GND IOUT C opyright © A NPEC Electronics Corp. Rev. A.3 - Oct., 2008 7 www.anpec.com.tw APW7079 Function Description Control Scheme The converter monitors the output voltage. When the internal feedback voltage falls below the reference voltage, the main switch turns on and the inductor current ramps up. The main switch turns off when the current reaches the peak current limit of typical 600mA. The second criterion that turns off the switch is the maximum on-time of 4µs (typical). As the main switch is turned off, the synchronous switch is turned on and delivers the current to the output. The main switch remains off for a minimum of 900ns (typical), or until the internal feedback voltage drops below the reference voltage. By the control scheme with low quiescent current of 11µA (typical), the converter gets high efficiency over a wide load range. Start-Up A startup oscillator circuit is integrated in the APW7079. When the power is applied to the device, the circuit pumps the output voltage high. Once the output voltage reaches 1.4V (typ), the main DC-DC circuitry turns on and boosts the output voltage to the final regulation point. Synchronous Rectification The internal synchronous rectifier eliminates the need for an external Schottky diode, thus reducing cost and board space. During the cycle off-time, the P-channel MOSFET turns on and shunts the MOSFET body diode. As a rewsult, the synchronous rectifier significantly improves efficiency without the addition of an external component. Conversion efficiency can be as high as 92%. Over-Temperature Protection The over-temperature circuit limits the junction temperature of the APW7079. When the junction temperature exceeds 150 ° C, a thermal sensor turns off the power MOSFETs, allowing the devices to cool. The thermal sensor allows the converter to start a start-up process and regulate the output voltage again after the junction temperature cools by 40°C.The OTP is designed with a 40°C hysteresis to lower the average TJ during continuous thermal overload conditions, increasing lifetime of the device. C opyright © A NPEC Electronics Corp. Rev. A.3 - Oct., 2008 8 www.anpec.com.tw APW7079 Application Information Input Capacitor Selection The input capacitor is chosen based on the voltage rating and the RMS current rating. For reliable operation, it is recommended to select the capacitor voltage rating at least 1.3 times higher than the maximum input voltage. The maximum RMS current rating of the input capacitor is calculated as the following equation: IRMS = where 1 VIN ⋅ TON L 3 ⋅ Since the output ripple is the product of the peak inductor current and the output capacitor ESR, using low-ESR tantalum capacitors for the best performance or connecting two or more filter capacitors in parallel is recommended. Inductor Selection The inductor value determines the inductor ripple current and affects the load transient response. It is recommended to select the boost inductor in order to keep the maximum peak inductor current below the current limit threshold of the power switch. For example, the current limit threshold of the APW7079’ switch is 600mA. For s choosing an inductor which has peak current passed, firstly, it is necessary to consider the output load (IOUT), input (VIN), and output voltage (VOUT). Secondly, the desired current ripple in the inductor also needed to be taken into account. The current was calculated in “Output Capacitor Selection”. Since the output ripple is the product of the peak inductor current and the output capacitor ESR, the larger inductor value reduces the inductor current ripple and output voltage ripple but typically offers a larger physical size. The inductor value also slightly affects the maximum output current. The maximum output current can be calculated as below: VIN   VOUT − VIN ILIM − TOFF   VOUT  2×L    ⋅ η   TON = main switch max. on-time (4µs typical) VIN = input voltage L = inductor value in µ H The capacitors should be placed close to the inductor and the GND. Output Capacitor Selection An output capacitor is required to filter the output and supply the load transient current. The output ripple is the sum of the voltages across the ESR and the ideal output capacitor. The peak-to-peak voltage of the ESR is calculated as the following equations: ∆VESR = IPEAK x ESR IPEAK = VOUT ⋅ IOUT VIN ⋅ TON + ≤ ILIM VIN ⋅ η 2 ⋅L Where IPEAK = peak current of inductor in amp where IOUT (MAX ) = η = efficiency (0.85 typical) The peak-to-peak voltage of the ideal output capacitor is calculated as the following equation: ∆VCOUT = IOUT × TON COUT TOFF = main switch min. off-time (0.9µs typical) Therefore, to consider the balance of the efficiency and component size, an inductor value of 22µH to 47 µH is recommended in most applications. VIN IIN ILX LX ISWP CIN N-FET ISWN P-FET ESR COUT IOUT VOUT For the applications using tantalum capacitors, the ∆VCOUT is much smaller than the V ESR and can be ignored. Therefore, the AC peak-to-peak output voltage (∆VOUT) is shown as below: ∆VOUT = IPEAK x ESR C opyright © A NPEC Electronics Corp. Rev. A.3 - Oct., 2008 9 www.anpec.com.tw APW7079 Application Information (Cont.) ILX ILIM IPEAK IIN T J = TA + TR where TA = the ambient temperature. The power dissipation can be calculated as below: PD = POUT x (1-η)/η where POUT = Output power (VOUT x IOUT) η = Efficiency As an example, the APW7079-18 converts an input voltage 1.2V to provide a load current of 175mA at ambient temperature of 85°C. Assume the efficiency (η) is 0.75. Therefore, the power dissipated on the converter is: ISWN ISWP PD = 1.8 x 0.175 x (1-0.75)/0.75= 0.105 Watt IOUT VOUT VOUT IPEAK x ESR Since the power dissipation includes the loss of external components, the actual value is slightly lower. For the SOT-89 package, the θJA is 180°C/W. Thus, the junction temperature of the regulator is as below: TJ = 85°C + (PD)(180) = 104 °C The maximum junction temperature should be less than 125°C. Note that, the junction temperature is lower at higher output voltages due to reduced switch resistance. Layout Consideration For all switching power supplies especially with high peak currents and switching frequency, the layout is an important step in the design. If the layout is not carefully done, the regulator may show noise problems and duty cycle jitter. 1. The input capacitor should be placed close to the device, which can reduce copper trace resistance and effect input ripple of the IC. 2.The inductor should be placed as close as possible to the switch pin to minimize the switching noise. 3.The output capacitor should be place closed to the VOUT and the GND. Thermal Consideration In most applications, the APW7079 does not dissipate much heat due to its high efficiency. However, in applications where the APW7079 is running at high ambient temperature with low output voltage, the heat dissipated may exceed the maximum junction temperature of the part. If the junction temperature reaches approximately 150°C, both power switches will be turned off and the LX node will become high impedance. To avoid the APW7079 from exceeding the maximum junction temperature, the user will need to do some thermal analysis. The goal of the thermal analysis is to determine whether the power dissipated exceeds the maximum junction temperature of the part. The temperature rise is given by: TR = (PD)(θJA) where PD is the power dissipated by the regulator and θJA is the thermal resistance from the junction of the die to the ambient temperature. The junction temperature, TJ, is given by: C opyright © A NPEC Electronics Corp. Rev. A.3 - Oct., 2008 10 www.anpec.com.tw APW7079 Application Information (Cont.) Layout Consideration (Cont.) C opyright © A NPEC Electronics Corp. Rev. A.3 - Oct., 2008 11 www.anpec.com.tw APW7079 Package Information SOT-89 D D1 A C E e e1 B1 S Y M B O L A B B1 C D D1 E E1 e e1 H L 3.94 0.89 B SOT-89 MILLIMETERS INCHES MIN. 0.055 0.017 0.014 0.014 0.173 0.064 0.090 0.084 0.059 BSC 0.118 BSC 4.25 1.20 0.155 0.035 0.167 0.047 MAX. 0.063 0.022 0.019 0.017 0.181 0.072 0.102 0.090 MIN. 1.40 0.44 0.36 0.35 4.40 1.62 2.29 2.13 1.50 BSC 3.00 BSC MAX. 1.60 0.56 0.48 0.44 4.60 1.83 2.60 2.29 Note : Follow JEDEC TO-243 AA. C opyright © A NPEC Electronics Corp. Rev. A.3 - Oct., 2008 L 12 H E1 www.anpec.com.tw APW7079 Carrier Tape & Reel Dimensions OD0 P0 P2 P1 A E1 F K0 B SECTION A-A T B0 A0 OD1 B A SECTION B-B d Application A 178.0± 2.00 H 50 MIN. P1 8.0± 0.10 H A T1 T1 12.4+2.00 -0.00 P2 2.0± 0.05 C 13.0+0.50 -0.20 D0 1.5+0.10 -0.00 d 1.5 MIN. D1 1.5 MIN. D 20.2 MIN. T 0.6+0.00 -0.40 W 12.0± 0.30 A0 4.80± 0.20 W E1 1.75± 0.10 B0 4.50± 0.20 F 5.50± 0.05 K0 1.80± 0.20 SOT-89 P0 4.0± 0.10 (mm) Devices Per Unit Package Type SOT-89 Unit Tape & Reel Quantity 1000 C opyright © A NPEC Electronics Corp. Rev. A.3 - Oct., 2008 13 www.anpec.com.tw APW7079 Taping Direction Information SOT-89 USER DIRECTION OF FEED Reflow Condition TP (IR/Convection or VPR Reflow) tp Critical Zone TL to TP Ramp-up TL Temperature tL Tsmax Tsmin Ramp-down ts Preheat 25 t 25°C to Peak Time Reliability Test Program Test item SOLDERABILITY HOLT PCT TST ESD Latch-Up Method MIL-STD-883D-2003 MIL-STD-883D-1005.7 JESD-22-B, A102 MIL-STD-883D-1011.9 MIL-STD-883D-3015.7 JESD 78 14 Description 245°C, 5 sec 1000 Hrs Bias @125°C 168 Hrs, 100%RH, 121°C -65°C~150°C, 200 Cycles VHBM > 2KV, VMM > 200V 10ms, 1tr > 100mA www.anpec.com.tw C opyright © A NPEC Electronics Corp. Rev. A.3 - Oct., 2008 APW7079 Classification Reflow Profiles Profile Feature Average ramp-up rate (TL to TP) Preheat - Temperature Min (Tsmin) - Temperature Max (Tsmax) - Time (min to max) (ts) Time maintained above: - Temperature (TL) - Time (tL) Peak/Classification Temperature (Tp) Time within 5°C of actual Peak Temperature (tp) Ramp-down Rate Time 25°C to Peak Temperature Sn-Pb Eutectic Assembly 3°C/second max. 100°C 150°C 60-120 seconds 183°C 60-150 seconds See table 1 10-30 seconds 6°C/second max. 6 minutes max. Pb-Free Assembly 3°C/second max. 150°C 200°C 60-180 seconds 217°C 60-150 seconds See table 2 20-40 seconds 6°C/second max. 8 minutes max. Note: All temperatures refer to topside of the package. Measured on the body surface. Table 1. SnPb Eutectic Process – Package Peak Reflow Temperatures Package Thickness