DATA SHEET AAT1151 850kHz 700mA Synchronous Buck DC/DC Converter General Description Features The AAT1151 SwitchReg™ is a step-down switching converter ideal for applications where high efficiency is required over the full range of output load conditions. The 2.7V to 5.5V input voltage range makes the AAT1151 ideal for single-cell lithium-ion/polymer battery applications. Capable of more than 700mA with internal MOSFETs, the current-mode controlled IC provides high efficiency using synchronous rectification. Fully integrated compensation simplifies system design and lowers external parts count. • • • • • • • • • • • • • • • • • • The device operates at a fixed 850kHz switching frequency and enters Pulse Frequency Modulation (PFM) mode for light load current to maintain high efficiency across all load conditions. The AAT1151 is available in Pb-free MSOP-8 and QFN3316 packages and is rated over the -40°C to +85°C temperature range. VIN Range: 2.7V to 5.5V Up to 95% Efficiency High Initial Accuracy ±1% 110m RDS(ON) Internal Switches <1μA Shutdown Current 850kHz Switching Frequency Fixed VOUT or Adjustable VOUT ≥1.0V Integrated Power Switches Synchronous Rectification Current Mode Operation Internal Compensation Stable with Ceramic Capacitors PFM for Optimum Efficiency for All Load Conditions Internal Soft Start Over-Temperature Protection Current Limit Protection MSOP-8 and QFN33-16 Packages -40°C to +85°C Temperature Range Applications • • • • • • • Cellular Phones Digital Cameras MP3 Players Notebook Computers PDAs USB-Powered Equipment Wireless Notebook Adapters Typical Application INPUT VP 10μF FB AAT1151 3.0μH LX ENABLE 100Ω VCC OUTPUT SGND PGND 2x 22μF 0.1μF Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com 201991B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013 1 DATA SHEET AAT1151 850kHz 700mA Synchronous Buck DC/DC Converter Pin Descriptions Pin # MSOP-8 QFN33-16 Symbol 1 4 FB 2 5, 6 SGND 3 7 EN 4 9 VCC 5 10, 11, 12 VP 6, 7 13, 14, 15 LX 8 1, 2, 3 PGND 8, 16 EP NC Function Feedback input pin. This pin is connected to the converter output. It is used to set the output of the converter to regulate to the desired value via an internal resistive divider. For an adjustable output, an external resistive divider is connected to this pin on the 1V model. Signal ground. Connect the return of all small signal components to this pin. (See board layout rules.) Enable input pin. A logic high enables the converter; a logic low forces the AAT1151 into shutdown mode reducing the supply current to less than 1μA. The pin should not be left floating. Bias supply. Supplies power for the internal circuitry. Connect to input power via low pass filter with decoupling to SGND. Input supply voltage for the converter power stage. Must be closely decoupled to PGND. Connect inductor to these pins. Switching node internally connected to the drain of both highand low-side MOSFETs. Main power ground return pin. Connect to the output and input capacitor return. (See board layout rules.) Not internally connected. Exposed paddle (bottom); connect to PGND directly beneath package Pin Configuration MSOP-8 (Top View) QFN33-16 (Top View) LX LX LX NC 12 2 11 3 10 4 9 VP VP VP VCC 8 VP 1 7 5 13 4 LX 14 VCC 6 PGND PGND PGND FB 6 3 LX 5 EN 7 15 2 PGND 16 SGND 8 2 1 1 FB NC EN SGND SGND 2 Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com 201991B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013 DATA SHEET AAT1151 850kHz 700mA Synchronous Buck DC/DC Converter Absolute Maximum Ratings1 Symbol VCC, VP VLX VFB VEN TJ VESD Description VCC, VP to GND LX to GND FB to GND EN to GND Operating Junction Temperature Range ESD Rating2 - HBM Value Units 6 -0.3 to VP + 0.3 -0.3 to VCC + 0.3 -0.3 to 6 -40 to 150 3000 V V V V °C V Value Units Thermal Characteristics3 Symbol Description JA Thermal Resistance PD Maximum Power Dissipation (TA = 25°C) MSOP-8 QFN33-16 MSOP-84 QFN33-165 150 50 667 2.0 °C/W mW W Recommended Operating Conditions Symbol T Description Ambient Temperature Range Value Units -40 to 85 °C 1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at conditions other than the operating conditions specified is not implied. Only one Absolute Maximum Rating should be applied at any one time. 2. Human body model is a 100pF capacitor discharged through a 1.5k resistor into each pin. 3. Mounted on a demo board. 4. Derate 6.7mW/°C above 25°C. 5. Derate 20mW/°C above 25°C. Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com 201991B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013 3 DATA SHEET AAT1151 850kHz 700mA Synchronous Buck DC/DC Converter Electrical Characteristics1 VIN = VCC = VP = 5V, TA = -40°C to 85°C, unless otherwise noted. Typical values are at TA = 25°C. Symbol Description VIN VOUT Input Voltage Range Output Voltage Tolerance VUVLO Under-Voltage Lockout VUVLO(HYS) IIL IIH IQ ISHDN ILIM RDS(ON)H RDS(ON)L VOUT (VOUT*VIN) VOUT/VOUT FOSC VEN(L) VEN(H) TSD THYS Conditions VIN = VOUT + 0.2 to 5.5V, IOUT = 0 to 700mA VIN Rising VIN Falling Under-Voltage Lockout Hysteresis Input Low Current Input High Current Quiescent Supply Current Shutdown Current Current Limit High Side Switch On Resistance Low Side Switch On Resistance Efficiency VIN = VFB = 5.5V VIN = VFB = 0V No Load, VFB = 0V, VIN = 4.2V, TA = 25°C VEN = 0V, VIN = 5.5V TA = 25°C TA = 25°C TA = 25°C IOUT = 300mA, VIN = 3.5V Load Regulation VIN = 4.2V, ILOAD = 0 to 700mA Line Regulation Oscillator Frequency Enable Threshold Low Enable Threshold High Over-Temperature Shutdown Threshold Over-Temperature Shutdown Hysteresis VIN = 2.7V to 5.5V TA = 25°C Min Typ 2.7 -3.0 Max Units 5.5 +3.0 2.5 V % 1.2 250 210 1.0 1.0 300 1.0 1.2 110 100 92 150 150 0.9 600 0.1 850 V mV μA μA μA μA A m m % % 1200 0.6 1.4 140 15 %/V kHz V V °C °C 1. The AAT1151 is guaranteed to meet performance specifications over the -40°C to +85°C operating range and is assured by design, characterization, and correlation with statistical process controls. 4 Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com 201991B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013 DATA SHEET AAT1151 850kHz 700mA Synchronous Buck DC/DC Converter Typical Characteristics Efficiency vs. Load Current Efficiency vs. Load Current (VOUT = 2.5V; L = 4.2μ μH) (VOUT = 1.8V) 100 Efficiency (%) Efficiency (%) 100 90 80 70 80 3.6V 70 50 1 10 100 1 1000 10 No Load Supply Current vs. Input Voltage 1000 Frequency vs. Input Voltage 300 890 T = 85°C 250 Frequency (kHz) Supply Current (μ μA) 100 Load Current (mA) Output Current (mA) 200 150 T = -40°C T = 25°C 100 50 880 870 860 850 0 2.5 3 3.5 4 4.5 5 2.5 5.5 Output Voltage vs. Temperature 3.5 4 4.5 5 5.5 Load and Line Regulation 3.0 1.794 2.0 1.79 1.0 VOUT Error (%) 1.792 1.788 1.786 1.784 1.782 1.78 -40 3 Input Voltage (V) Input Voltage (V) Output Voltage (V) 4.2V 60 60 50 2.7V 90 VIN = 4.2V VIN = 3.6V 0.0 VIN = 2.7V -1.0 -2.0 -20 0 20 40 60 Temperature (°°C) 80 100 -3.0 1 10 100 1000 Load Current (mA) Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com 201991B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013 5 DATA SHEET AAT1151 850kHz 700mA Synchronous Buck DC/DC Converter Typical Characteristics Output Ripple 1.8V, 50mA, VIN = 3.6V Circuit of Figure 1 Switching Frequency vs. Temperature Frequency (kHz) 1000 800 600 400 200 0 -40 -20 0 20 40 60 80 100 20 1.4 10 1.2 0 0.8 -20 0.6 -30 0.4 -40 0.2 -50 0 -60 -0.2 Time (2μ μs/div) Temperature (°°C) 4 80 3.8 60 3.6 40 3.4 20 3.2 0 3 -20 2.8 -40 Output Voltage (AC coupled) (top) (mV) 100 20 3.5 10 3 -10 2 -20 1.5 -30 1 -40 0.5 -50 0 Time (2μ μs/div) 100 4 80 3.8 60 3.6 40 3.4 20 3.2 0 3 -20 2.8 -40 Output Voltage (top) (mV) (AC coupled) 120 4.2 40 3.5 20 3 2.5 0 -20 2 -40 1.5 -60 1 -80 0.5 -100 0 -120 -0.5 Time (200μs/div) Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com 201991B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013 Inductor Current (bottom) (A) 4.4 Load Transient Response 50mA to 0.7A VIN = 3.6V − Circuit of Figure 1 Output Voltage (bottom) (mV) Input Voltage (top) (V) Line Transient Response 1.8V, 0.7A Circuit of Figure 1 6 -0.5 -60 Time (20μ μs/div) Time (20μ μs/div) 2.5 0 Inductor Current (bottom) (A) 120 4.2 Output Ripple 1.8V, 0.7A, VIN = 3.6V Circuit of Figure 1 Output Voltage (bottom) (mV) Input Voltage (top) (V) Line Transient Response 1.8V, 50mA Circuit of Figure 1 4.4 1 -10 Inductor Current (bottom) (A) Output Voltage (AC coupled) (top) (mV) 1200 DATA SHEET AAT1151 850kHz 700mA Synchronous Buck DC/DC Converter Typical Characteristics Output Ripple Circuit of Figure 1 3.5 3 3 2 2.5 1 2 0 1.5 -1 1 -2 0.5 -3 0 -4 -0.5 Time (200μ μs/div) 20 15 Ripple (mV) 4 Inductor Current (bottom) (A) Enable (top) Output (middle) (V) Soft Start 1.8V, 0.7A, VIN = 3.6V Circuit of Figure 1 VIN = 2.7V VIN = 3.6V 10 5 VIN = 4.2V 0 1 10 100 1000 Output Current (mA) Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com 201991B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013 7 DATA SHEET AAT1151 850kHz 700mA Synchronous Buck DC/DC Converter Functional Block Diagram VCC VP = 2.7V to 5.5V 1.0V REF FB OP. AMP CMP DH LOGIC 1MΩ LX DL Temp. Sensing OSC SGND Operation Control Loop The AAT1151 is a peak current mode buck converter. The inner wide bandwidth loop controls the peak current of the output inductor. The output inductor current is sensed through the P-channel MOSFET (high side) and is also used for short-circuit and overload protection. A fixed slope compensation signal is added to the sensed current to maintain stability. The loop appears as a voltage programmed current source in parallel with the output capacitor. The voltage error amplifier output programs the current loop for the necessary inductor current to force a constant output voltage for all load and line conditions. The voltage feedback resistive divider is internal, dividing the output voltage to the error amplifier reference voltage of 1.0V. The voltage error amplifier does not have the large DC gain typical of most error amplifiers. This eliminates the need for external compensation components, while still providing sufficient DC loop gain for load regulation. 8 EN PGND The voltage loop crossover frequency and phase margin are set by the output capacitor value only. PFM/PWM Operation Light load efficiency is maintained by way of PFM control. The AAT1151 PFM control forces the peak inductor current to a minimum level regardless of load demand. At medium to high load demand, this has no effect on circuit operation and normal PWM controls take over. PFM reduces the switching frequency at light loads, thus reducing the associated switching losses. Soft Start/Enable Soft start increases the inductor current limit point in discrete steps when the input voltage or enable input is applied. It limits the current surge seen at the input and eliminates output voltage overshoot. When pulled low, the enable input forces the AAT1151 into a low-power, non-switching state. The total input current during shutdown is less than 1μA. Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com 201991B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013 DATA SHEET AAT1151 850kHz 700mA Synchronous Buck DC/DC Converter Power and Signal Source current in the inductor can meet or exceed the current limit point of the AAT1151. These conditions can tolerate greater saturation in the inductor without degradation in converter performance. Some inductors may meet the peak and average current ratings yet result in excessive losses due to a high DCR. Always consider the losses associated with the DCR and its effect on the total converter efficiency when selecting an inductor. Separate small signal ground and power supply pins isolate the internal control circuitry from the noise associated with the output MOSFET switching. The low pass filter R1 and C2 in schematic Figure 1 filters the noise associated with the power switching. Current Limit and Over-Temperature Protection For a 1.0A load and the ripple set to 40% at the maximum input voltage, the maximum peak-to-peak ripple current is 280mA. The inductance value required is 2.84μH. For overload conditions, the peak input current is limited. As load impedance decreases and the output voltage falls closer to zero, more power is dissipated internally, raising the device temperature. Thermal protection completely disables switching when internal dissipation becomes excessive, protecting the device from damage. The junction over-temperature threshold is 140°C with 10°C of hysteresis. VOUT ⎛ VOUT⎞ L=I •k•F • 1- V ⎝ O S IN ⎠ = 1.5V ⎞ ⎛ ⎞⎛ • 1 - 1.5V 4.2V ⎠ ⎝ 1A • 0.4 • 850kHz ⎠ ⎝ = 2.84μH Inductor The output inductor is selected to limit the ripple current to some predetermined value, typically 20% to 40% of the full load current at the maximum input voltage. Manufacturer’s specifications list both the inductor DC current rating, which is a thermal limitation, and the peak current rating, which is determined by the saturation characteristics. The inductor should not show any appreciable saturation under normal load conditions. During overload and transient conditions, the average Efficiency vs. Load Current U1 AAT1151-MSOP 2.7V-4.2V 5 VP FB The factor “k” is the fraction of full load selected for the ripple current at the maximum input voltage. For ripple current at 40% of the full load current, the peak current will be 120% of full load. Selecting a standard value of 3.0μH gives 38% ripple current. A 3.0μH inductor selected from the Sumida CDRH5D28 series has a 24m DCR and a 2.4A DC current rating. At full load, the inductor DC loss is 24mW, which amounts to a 1.6% loss in efficiency. (VOUT = 1.8V) 1.8V 1 100 R1 100 4 VCC LX 7 3 EN LX 6 C3, C4 2x22µF C2 0.1µF 2 C1 C3-C4 L1 L1 3.3µH SGND PGND 8 Murata 10µF 6.3V X5R GRM42-6X5R106K6.3 Murata 22µF 6.3V GRM21BR60J226ME39L X5R 0805 Sumida CDRH3D16-4R7NC or CDRH3D16-3R3NC Efficiency (%) C1 10µF R2 100k 2.7V 90 80 3.6V 4.2V 70 60 50 1 10 100 1000 Load Current (mA) Figure 1: AAT1151 Evaluation Board. Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com 201991B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013 9 DATA SHEET AAT1151 850kHz 700mA Synchronous Buck DC/DC Converter Input Capacitor The primary function of the input capacitor is to provide a low impedance loop for the edges of pulsed current drawn by the AAT1151. A low ESR/ESL ceramic capacitor is ideal for this function. To minimize stray inductance, the capacitor should be placed as close as possible to the IC. This keeps the high frequency content of the input current localized, minimizing radiated and conducted EMI while facilitating optimum performance of the AAT1151. Ceramic X5R or X7R capacitors are ideal for this function. The size required will vary depending on the load, output voltage, and input voltage source impedance characteristics. A typical value is around 10μF. The input capacitor RMS current varies with the input voltage and the output voltage. The equation for the RMS current in the input capacitor is: IRMS = IO • VO ⎛ V ⎞ • 1- O VIN ⎝ VIN ⎠ The input capacitor RMS ripple current reaches a maximum when VIN is two times the output voltage where it is approximately one half of the load current. Losses associated with the input ceramic capacitor are typically minimal and are not an issue. Proper placement of the input capacitor can be seen in the reference design layout in Figures 2 and 4. Output Capacitor Since there are no external compensation components, the output capacitor has a strong effect on loop stability. Lager output capacitance will reduce the crossover frequency with greater phase margin. For the 1.5V 1A design using the 4.1μH inductor, two 22μF capacitors provide a stable output. In addition to assisting stability, the output capacitor limits the output ripple and provides 10 holdup during large load transitions. The output capacitor RMS ripple current is given by: IRMS = 1 VOUT · (VIN - VOUT) L · FS · VIN 2· 3 · For a ceramic capacitor, the ESR is so low that dissipation due to the RMS current of the capacitor is not a concern. Tantalum capacitors with sufficiently low ESR to meet output voltage ripple requirements also have an RMS current rating well beyond that actually seen in this application. Layout Figures 2 through 5 display the suggested PCB layout for the AAT1151. The following guidelines should be used to help ensure a proper layout. • The input capacitor (C1) should connect as closely as possible to VP (Pin 5) and PGND (Pin 8). • C2 and L1 should be connected as closely as possible. The connection L1 to the LX node should be as short as possible. • The feedback trace (Pin 1) should be separate from any power trace and connect as closely as possible to the load point. Sensing along a high-current load trace will degrade DC load regulation. • The resistance of the trace from the load return to the PGND (Pin 8) should be kept to a minimum. This will help to minimize any error in DC regulation due to differences in the potential of the internal signal ground and the power ground. • Low pass filter R1 and C3 provide a cleaner bias source for the AAT1151 active circuitry. C3 should be placed as closely as possible to SGND (Pin 2) and VCC (Pin 4). See Figures 2 and 7. Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com 201991B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013 DATA SHEET AAT1151 850kHz 700mA Synchronous Buck DC/DC Converter Figure 2: MSOP Evaluation Board Top Layer. Figure 3: MSOP Evaluation Board Bottom Layer. Figure 4: QFN Evaluation Board Top Side. Figure 5: QFN Evaluation Board Bottom Side. 45 R4=10kΩ 40 2.7V - 5.5V AAT1151-1.0 10,11,12 35 R1 100 R3 (kΩ) 30 25 R2 20 100k C1 10μF 15 10 5 C3 0.1μF 9 7 5,6 VP FB VCC LX 4 13,14,15 L1 3.3μH EN SGND PGND VO+ 1.25V 0.7A R3 2.55k 1% 1,2,3 R4 10kΩ 1% C2, C4 2x 22μF GND 0 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 Output Voltage (V) Figure 6: R3 vs. VOUT for Adjustable Output C1 Murata 10μF 6.3V X5R GRM42-6X5R106K6.3 C2, C4 Murata 22μF 6.3V GRM21BR60J226ME39L X5R 0805 L1 Sumida CDRH3D16-3R3 NC Figure 7: Adjustable Output Schematic. Using the AAT1151-1.0V. Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com 201991B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013 11 DATA SHEET AAT1151 850kHz 700mA Synchronous Buck DC/DC Converter Thermal Calculations There are two types of losses associated with the AAT1151 output switching MOSFET: switching losses and conduction losses. Conduction losses are associated with the RDS(ON) characteristics of the output switching device. At the full load condition, assuming continuous conduction mode (CCM), a simplified form of the total losses is given by: P= IO2 · (RDS(ON)H · VO + RDS(ON)L · (VIN · VO)) V IN + (t SW · FS · I O · VIN + IQ) · VIN where Iq is the AAT1151 quiescent current. 12 Once the total losses have been determined, the junction temperature can be derived from the JA for the MSOP-8 package. TJ = P · θJA + TAMB Adjustable Output For applications requiring an output other than the fixed available, the 1V version can be programmed externally. Resistors R3 and R4 of Figure 7 force the output to regulate higher than 1V. R4 should be 100 times less than the 1M internal resistance of the FB pin (recommended 10k). Once R4 is selected, R3 can be calculated. For a 1.25 volt output with R4 set to 10.0k, R3 is 2.55k. R3 = (VO - 1) · R4 = 0.25 · 10kΩ = 2.55kΩ Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com 201991B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013 DATA SHEET AAT1151 850kHz 700mA Synchronous Buck DC/DC Converter Design Example Specifications IOUT = 0.7A IRIPPLE = 40% of Full Load at Max VIN VOUT = 1.5V VIN = 2.7V to 4.2V (3.6V nominal) FS = 850kHz TAM = 85°C Maximum Input Capacitor Ripple IRMS = I O · VO ⎛ V ⎞ · 1 - O = 0.35Arms, VIN = 2 · VO VIN ⎝ VIN ⎠ P = esr · IRMS2 = 5mΩ · 0.352 A = 0.6mW Inductor Selection L= ⎛ V ⎞ VOUT 1.5V ⎛ 1.5V⎞ ⋅ 1 - OUT = ⋅1= 4.05μH IO ⋅ k ⋅ FS ⎝ VIN ⎠ 0.7A ⋅ 0.4 ⋅ 850kHz ⎝ 4.2V⎠ Select Sumida inductor CDRH3D16, 3.3μH, 63m, 1.8mm height. ΔI = ⎛ 1.5V⎞ VO ⎛ V ⎞ 1.5V ⋅ 1- O = ⋅ 1= 340mA L ⋅ FS ⎝ VIN⎠ 3.3μH ⋅ 850kHz ⎝ 4.2V⎠ IPK = IOUT + ΔI = 0.7A + 0.17A = 0.87A 2 P = IO2 ⋅ DCR = (0.7)2 ⋅ 63mΩ = 31mW Output Capacitor Ripple Current IRMS = VOUT · (VIN - VOUT) 1 1.5V · (4.2V - 1.5V) · = 99mArms = L · FS · VIN 2 · 3 3.3μH · 850kHz · 4.2V 2· 3 1 · Pesr = esr · IRMS2 = 5mΩ · 992 mA = 50μW Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com 201991B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013 13 DATA SHEET AAT1151 850kHz 700mA Synchronous Buck DC/DC Converter AAT1151 Dissipation PTOTAL = = IO2 • (RDS(ON)H • VO + RDS(ON)L • (VIN -VO)) VIN + (tsw • FS • IO + IQ) • VIN (0.7A)2 • (0.2Ω • 1.5V + 0.187Ω • (4.2V - 1.5V)) 4.2V + (20nsec • 850kHz • 0.7A + 0.3mA) • 4.2V = 0.145W TJ(MAX) = TAMB + ΘJA • PLOSS = 85°C + 150°C/W • 0.145W = 107°C (MSOP-8) = 85°C + 50°C/W • 0.145W = 92°C (QFN33-16) Manufacturer Part Number Value Max DC Current DCR (Ω) Taiyo Yuden Toko Sumida Sumida Sumida Murata Murata Murata NPO5DB4R7M A914BYW-3R5M-D52LC CDRH5D28-3R0 CDRH5D28-4R2 CDRH5D18-4R1 LQH55DN4R7M03 LQH66SN4R7M03 CDRH3D16-3R3 4.7μH 3.5μH 3.0μH 4.2μH 4.1μH 4.7μH 4.7μH 3.3μH 1.4A 1.34A 2.4A 2.2A 1.95A 2.7A 2.2A 1.1A 0.038 0.073 0.024 0.031 0.057 0.041 0.025 0.063 Size (mm) LxWxH 5.9 5.0 5.7 5.7 5.7 5.0 6.3 3.8 x x x x x x x x 6.1 5.0 5.7 5.7 5.7 5.0 6.3 3.8 x x x x x x x x 2.8 2.0 3.0 3.0 2.0 4.7 4.7 1.8 Type Shielded Shielded Shielded Shielded Shielded Non-Shielded Shielded Shielded Table 1: Surface Mount Inductors. Manufacturer Part Number Value Voltage Temp. Co. Case Murata Murata Murata Murata GRM40 X5R 106K 6.3 GRM42-6 X5R 106K 6.3 GRM21BR60J226ME39L GRM21BR60J106ME39L 10μF 10μF 22μF 10μF 6.3V 6.3V 6.3V 6.3V X5R X5R X5R X5R 0805 1206 0805 0805 Table 2: Surface Mount Capacitors. 14 Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com 201991B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013 DATA SHEET AAT1151 850kHz 700mA Synchronous Buck DC/DC Converter Ordering Information Output Voltage1 Package Marking2 Part Number (Tape and Reel)3 1.0V (Adj. VOUT ≥ 1.0V) 1.8V 2.5V 3.3V QFN33-16 MSOP-8 QFN33-16 MSOP-8 JHXYY JIXYY JJXYY NKXYY AAT1151IVN-1.0-T1 AAT1151IKS-1.8-T1 AAT1151IVN-2.5-T1 AAT1151IKS-3.3-T1 Skyworks Green™ products are compliant with all applicable legislation and are halogen-free. For additional information, refer to Skyworks Definition of Green™, document number SQ04-0074. Package Information4 MSOP-8 4° ± 4° 4.90 ± 0.10 3.00 ± 0.10 1.95 BSC 0.95 REF 0.60 ± 0.20 PIN 1 3.00 ± 0.10 0.85 ± 0.10 0.95 ± 0.15 10° ± 5° GAUGE PLANE 0.254 BSC 0.155 ± 0.075 0.075 ± 0.075 0.65 BSC 0.30 ± 0.08 All dimensions in millimeters. 1. 2. 3. 4. Contact local sales office for custom options. XYY = assembly and date code. Sample stock is generally held on part numbers listed in BOLD. The leadless package family, which includes QFN, TQFN, DFN, TDFN and STDFN, has exposed copper (unplated) at the end of the lead terminals due to the manufacturing process. A solder fillet at the exposed copper edge cannot be guaranteed and is not required to ensure a proper bottom solder connection. Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com 201991B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013 15 DATA SHEET AAT1151 850kHz 700mA Synchronous Buck DC/DC Converter QFN33-16 Pin 1 Dot By Marking 0.230 ± 0.050 Pin 1 Identification 0.500 ± 0.050 1.250 ± 0.050 5 C0.3 13 9 1.250 ± 0.050 Top View 0.025 ± 0.025 Bottom View 0.214 ± 0.036 0.900 ± 0.100 3.000 ± 0.050 0.400 ± 0.100 3.000 ± 0.050 1 Side View All dimensions in millimeters. Copyright © 2012, 2013 Skyworks Solutions, Inc. All Rights Reserved. Information in this document is provided in connection with Skyworks Solutions, Inc. (“Skyworks”) products or services. These materials, including the information contained herein, are provided by Skyworks as a service to its customers and may be used for informational purposes only by the customer. Skyworks assumes no responsibility for errors or omissions in these materials or the information contained herein. Skyworks may change its documentation, products, services, specifications or product descriptions at any time, without notice. Skyworks makes no commitment to update the materials or information and shall have no responsibility whatsoever for conflicts, incompatibilities, or other difficulties arising from any future changes. No license, whether express, implied, by estoppel or otherwise, is granted to any intellectual property rights by this document. Skyworks assumes no liability for any materials, products or information provided hereunder, including the sale, distribution, reproduction or use of Skyworks products, information or materials, except as may be provided in Skyworks Terms and Conditions of Sale. THE MATERIALS, PRODUCTS AND INFORMATION ARE PROVIDED “AS IS” WITHOUT WARRANTY OF ANY KIND, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHERWISE, INCLUDING FITNESS FOR A PARTICULAR PURPOSE OR USE, MERCHANTABILITY, PERFORMANCE, QUALITY OR NON-INFRINGEMENT OF ANY INTELLECTUAL PROPERTY RIGHT; ALL SUCH WARRANTIES ARE HEREBY EXPRESSLY DISCLAIMED. SKYWORKS DOES NOT WARRANT THE ACCURACY OR COMPLETENESS OF THE INFORMATION, TEXT, GRAPHICS OR OTHER ITEMS CONTAINED WITHIN THESE MATERIALS. SKYWORKS SHALL NOT BE LIABLE FOR ANY DAMAGES, INCLUDING BUT NOT LIMITED TO ANY SPECIAL, INDIRECT, INCIDENTAL, STATUTORY, OR CONSEQUENTIAL DAMAGES, INCLUDING WITHOUT LIMITATION, LOST REVENUES OR LOST PROFITS THAT MAY RESULT FROM THE USE OF THE MATERIALS OR INFORMATION, WHETHER OR NOT THE RECIPIENT OF MATERIALS HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. Skyworks products are not intended for use in medical, lifesaving or life-sustaining applications, or other equipment in which the failure of the Skyworks products could lead to personal injury, death, physical or environmental damage. Skyworks customers using or selling Skyworks products for use in such applications do so at their own risk and agree to fully indemnify Skyworks for any damages resulting from such improper use or sale. Customers are responsible for their products and applications using Skyworks products, which may deviate from published specifications as a result of design defects, errors, or operation of products outside of published parameters or design specifications. Customers should include design and operating safeguards to minimize these and other risks. Skyworks assumes no liability for applications assistance, customer product design, or damage to any equipment resulting from the use of Skyworks products outside of stated published specifications or parameters. Skyworks, the Skyworks symbol, and “Breakthrough Simplicity” are trademarks or registered trademarks of Skyworks Solutions, Inc., in the United States and other countries. Third-party brands and names are for identification purposes only, and are the property of their respective owners. Additional information, including relevant terms and conditions, posted at www.skyworksinc.com, are incorporated by reference. 16 Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com 201991B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 18, 2013