Low Input Voltage and High Efficiency Synchronous Boost Converter with 1.3A Switch ISL9113A Features The ISL9113A provides a power supply solution for devices powered by three-cell alkaline, NiCd, NiMH, or one-cell Li-Ion/Li-Polymer batteries. It offers either a fixed 5V or an adjustable output option for USB-OTG or portable HDMI applications. The device is guaranteed to supply 500mA from a 3V input and 5V output, and has a typical 1.3A peak current limit. High 1.8MHz switching frequency allows for the use of tiny, low-profile inductors and ceramic capacitors to minimize the size of the overall solution. • Up to 95% efficiency at typical operating conditions • Input voltage range: 0.8V to 4.7V • Output current: Up to 500mA (VBAT = 3.0V, VOUT = 5.0V) • Low quiescent current: 20μA (typical) • Logic control shutdown (IQ < 1µA) • 1.2V EN high logic • Output disconnect during shutdown The ISL9113A is an internally compensated, fully integrated synchronous converter optimized for efficiency with minimal external components. At light load, the device enters skip mode and consumes only 20µA of quiescent current, resulting in higher efficiency at light loads and maximum battery life. • Skip mode under light load condition The device is available in an 8 Ld DFN package. Applications • Undervoltage lockout • Fault protection: OVP, OTP, short circuit • 8 Ld 2mmx2mm DFN Package • Products including portable HDMI and USB-OTG • Smartphones • Tablet and mobile internet devices Related Literature • See AN1816 “ISL9113AIRAZ-EVZ Evaluation Board User Guide” 2.2µH 100 VBAT = 4.2V VBAT = 3.6V 95 8 VOUT 7 2 R1 523k VBAT 4.7µF 5 FB EN GND 4 1 R2 100k 4.7µF VBAT = 3.0V 85 EFFICIENCY (%) SW VBAT = 0.8 TO 4.7V 90 VOUT = 5.0V/500mA 80 75 VBAT = 2.3V 70 VBAT = 1.2V 65 60 55 50 0.0001 FIGURE 1. TYPICAL APPLICATION December 19, 2013 FN8620.0 1 VOUT = 5.0V 0.001 0.01 LOAD CURRENT (A) 0.1 1 FIGURE 2. EFFICIENCY CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 1-888-468-3774 | Copyright Intersil Americas LLC 2013. All Rights Reserved Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries. All other trademarks mentioned are the property of their respective owners. ISL9113A Block Diagram C1 VOUT VBAT C2 7 UVLO VINT 2 VOLTAGE SELECTOR START-UP N-WELL SWITCH GATE DRIVER VOUT OVP SW L1 8 AND ANTI-CROSS CONDUCTION ZCD EN VOUT 5 ON CURRENT SENSE CONTROL LOGIC R1 AND DIGITAL SOFT-START CURRENT LIMIT SLOPE COMP FB FAULT MONITORING 4 gm R2 VOLTAGE CLAMP 1.8MHz OSCILLATOR REFERENCE GENERATOR THERMAL SHUTDOWN 1 2 VINT OFF SW 6 FN8620.0 December 19, 2013 ISL9113A Pin Configuration Pin Descriptions ISL9113A (8 LD DFN) TOP VIEW PGND 1 8 SW VOUT 2 7 VBAT NC 3 6 AGND FB 4 5 EN PIN NUMBER PIN NAME 1 PGND Power ground. 2 VOUT Device output. 3 NC No connection. 4 FB Feedback pin of the converter. Connect voltage divider resistors between VOUT, FB and GND for desired output. 5 EN The EN pin is an active-HIGH logic input for enabling the device. When asserted HIGH, the boost function begins. When asserted LOW, the device is completely disabled, and current is blocked from flowing from the SW pin to the output and vice versa. This pin should be tied either HIGH to enable the device, or LOW to disable the device. 6 AGND 7 VBAT Device input supply from a battery. Connect a 4.7µF ceramic capacitor to the power ground. 8 SW The SW pin is the switching node of the power converter. Connect one terminal of the inductor to the SW pin and the other to power input. EPAD The exposed pad (available only in the 8 Ld DFN package) must be connected to PGND pin for proper electrical performance. Place as many vias as possible under the pad connecting to the system GND plane for optimal thermal performance. PIN DESCRIPTION Analog ground. Ordering Information PART NUMBER (Notes 1, 3) PART MARKING VOUT (V) TEMP RANGE (°C) Adjustable -40 to +85 ISL9113AIRAZ-T (Note 2) 3AA ISL9113AIRAZ-EVZ Evaluation Board for ISL9113AIRAZ-T PACKAGE (Pb-free) 8 Ld DFN PKG. DWG. # L8.2x2D NOTES: 1. Please refer to Tech Brief TB347 for details on reel specifications. 2. These Intersil Pb-free plastic packaged products employ special Pb-free material sets, molding compounds/die attach materials, and 100% matte tin plate plus anneal (e3 termination finish, which is RoHS compliant and compatible with both SnPb and Pb-free soldering operations). Intersil Pbfree products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020. 3. For Moisture Sensitivity Level (MSL), please see device information page for ISL9113A. For more information on MSL please see Tech Brief TB363. 3 FN8620.0 December 19, 2013 ISL9113A Absolute Maximum Ratings Thermal Information VBAT, EN, VOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 6.5V SW Voltage DC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to 6.5V Pulse < 10ns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to 8.0V ESD Ratings Human Body Model (Tested per JESD22-A114F) . . . . . . . . . . . . . . . . 3kV *Other ESD Spec should meet Level 1 requirement Latch Up (Tested per JESD78; Class 2, Level A) . . . . . . . . . . . . . . . . 100mA Thermal Resistance (Typical) θJA (°C/W) θJC (°C/W) 8 Ld DFN Package (Notes 4, 5). . . . . . . . . . 80 15 Junction Temperature Range . . . . . . . . . . . . . . . . . . . . . . . -40°C to+125°C Operating Temperature Range . . . . . . . . . . . . . . . . . . . . . . . -40°C to+85°C Storage Temperature Range. . . . . . . . . . . . . . . . . . . . . . . .-65°C to +150°C Pb-Free Reflow Profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . see link below http://www.intersil.com/pbfree/Pb-FreeReflow.asp Recommended Operating Conditions VBAT (After Start-up) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.8V to 4.7V VOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (VBAT + 0.2V) to 5.2V Ambient Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . -40°C to +85°C CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product reliability and result in failures not covered by warranty. NOTES: 4. θJA is measured in free air with the component mounted on a high effective thermal conductivity test board with “direct attach” features. See Tech Brief TB379. 5. For θJC the “case temp” location is the center of the exposed metal pad on the package underside. Electrical Specifications -40°C to +85°C. PARAMETER VBAT = 3.0V, VOUT = 5.0V, TA = +25°C. Boldface limits apply over the operating temperature range, SYMBOL TEST CONDITIONS Start-up Voltage VMIN VEN = VBAT, RLOAD = 50Ω Input Undervoltage Lockout VUVLO VEN = VBAT, RLOAD = 50Ω Feedback Voltage VFB Output Voltage VOUT VBAT = 2.8V MIN (Note 6) TYP MAX (Note 6) UNITS 0.66 0.75 0.9 V 0.70 0.76 V 784 800 816 mV 5.2 V 3.0 VFB = 0.8V Feedback Pin Input Current Quiescent Current from VOUT IQ1 VBAT = VEN = 1.2V, No Load (Note 7) 20 Shutdown Current from VBAT ISD VEN = 0V, VBAT = 1.2V, VO = 0 0.5 VEN = 0V, VBAT = 4.7V, VO = 0 Leakage Current at SW Pin 100 nA 45 μA 2.8 μA 1.0 μA N-Channel MOSFET ON-resistance 0.20 Ω P-Channel MOSFET ON-resistance 0.35 Ω IPK 1.1 1.3 Maximum Duty Cycle DMAX 82 87.5 PWM Switching Frequency FOSC 1.5 1.8 N-Channel MOSFET Peak Current Limit 2.5V < VBAT < 4.7V EN Logic High VBAT < 2.5V 0.48*VBAT ΔVOUT/VOUT Load Regulation 0.2 V 0.14*VBAT V 1 ms ILOAD = 0 to 50mA -1.5 +1.5 % VBAT = 3.0V to 3.6V, ILOAD = 1mA -1.0 +1.0 % Output Overvoltage Protection Threshold Thermal Shutdown MHz V 0.35 COUT = 4.7μF, L = 2.2μH Line Regulation 2.0 V VBAT < 2.5V Soft-Start-Up Time A % 1.2 2.5V < VBAT < 4.7V EN Logic Low 1.5 TSD Thermal Shutdown Hysteresis 5.9 V 150 oC 25 oC NOTES: 6. Compliance to datasheet limits is assured by one or more methods: production test, characterization and/or design. 7. IQ1 is measured at VOUT and multiplied by VOUT/VBAT; thus, the equivalent input quiescent current is calculated. 4 FN8620.0 December 19, 2013 ISL9113A Detailed Description Current Mode PWM Operation The control scheme of the device is based on the peak current mode control and the control loop is compensated internally. The peak current of the N-channel MOSFET switch is sensed to limit the maximum current flowing through the switch and the inductor. The typical current limit is set to 1.3A. The control circuit includes a ramp generator, slope compensator, error amplifier and a PWM comparator (see “Block Diagram” on page 2). The ramp signal is derived from the inductor current. This ramp signal is then compared to the error amplifier output to generate the PWM gating signals for driving both N-channel and P-channel MOSFETs. The PWM operation is initialized by the clock from the internal oscillator (typical 1.8MHz). The N-channel MOSFET is turned ON at the beginning of a PWM cycle, the P-channel MOSFET remains OFF, and the current starts ramping up. When the sum of the ramp and the slope compensator output reaches the error amplifier output voltage, the PWM comparator outputs a signal to turn OFF the N-channel MOSFET. Here, both MOSFETs remain OFF during the dead-time interval. Next, the P-channel MOSFET is turned ON and remains ON until the end of this PWM cycle. During this time, the inductor current ramps down until the next clock. At this point, following a short dead time, the N-channel MOSFET is again turned ON, repeating as previously described. Skip Mode Operation The boost converter is capable of operating in two different modes. When the inductor current is sensed to cross zero for eight consecutive times, the converter enters skip mode. In skip mode, each pulse cycle is still synchronized by the PWM clock. The N-channel MOSFET is turned ON at the rising edge of the clock and turned OFF when the inductor peak current reaches typically 25% of the current limit. Then, the P-channel MOSFET is turned ON, and it stays ON until its current goes to zero. Subsequently, both N-channel and P-channel MOSFETs are turned OFF until the next clock cycle starts, at which time the N-channel MOSFET is turned ON again. When VOUT is 1.5% higher than the nominal output voltage, the N-channel MOSFET is immediately turned OFF and the P-channel MOSFET is turned ON until the inductor current goes to zero. The N-channel MOSFET resumes operation when VFB falls back to its nominal value, repeating the previous operation. The converter returns to 1.8MHz PWM mode operation when VFB drops 1.5% below its nominal voltage. Given the skip mode algorithm incorporated in the ISL9113A, the average value of the output voltage is approximately 0.75% higher than the nominal output voltage under PWM operation. This positive offset improves the load transient response when switching from skip mode to PWM mode operation. The ripple on the output voltage is typically 1.5%*VOUT (nominal) when input voltage is sufficiently lower than output voltage, and it increases as the input voltage approaches the output voltage. Because the commonly used discrete Schottky rectifier is replaced with the low rDS(ON) P-channel MOSFET, the power conversion efficiency reaches a value above 90%. Since a typical step-up converter has a conduction path from the input to the output via the body diode of the P-channel MOSFET, a special circuit (see “Block Diagram” on page 2) is used to reverse the polarity of the P-channel body diode when the device is shut down. Thus, this configuration completely disconnects the load from the input during shutdown of the converter. The benefit of this feature is that the battery will not be completely depleted during shutdown of the converter. No additional components are needed to disconnect the battery from the output of the converter. Soft-Start The soft start-up duration is the time between the device being enabled and VOUT rising to within 3% of target voltage. When the device is enabled, the start-up cycle starts with a linear phase. During the linear phase, the rectifying switch is turned ON in a current limited configuration, delivering about 350mA, until the output capacitor is charged to approximately 90% of the input voltage. At this point, PWM operation begins in boost mode. If the output voltage is below 2.3V, PWM switching is done at a fixed duty-cycle of 75% until the output voltage reaches 2.3V. When the output voltage exceeds 2.3V, the closed-loop current mode PWM loop overrides the duty cycle until the output voltage is regulated. Peak inductor current is ramped to the final value (typically 1.3A) during the soft-start period to limit in-rush current from the input source. Fault monitoring begins approximately 2ms after the device is enabled. Over-temperature Protection (OTP) The device offers over-temperature protection. A temperature sensor circuit is integrated and monitors the internal IC temperature. Once the temperature exceeds the preset threshold (typically +150°C), the IC shuts down immediately. The OTP has a typical hysteresis of +25°C. When the device temperature decreases by this, the device starts operating. Printed Circuit Board Layout Recommendations The ISL9113A is a high frequency switching boost converter. Accordingly, the converter has fast voltage change and high switching current that may cause EMI and stability issues if the layout is not done properly. Therefore, careful layout is critical to minimize the trace inductance and reduce the area of the power loop. Power components, such as input capacitor, inductor, and output capacitor, should be placed close to the device. Board traces that carry high switching current should be routed wide and short. A solid power ground plane is important for EMI suppression. Synchronous Rectifier The switching node (SW pin) of the converter and the traces connected to this pin are very noisy. Noise sensitive traces, such as the FB trace, should be kept away from SW node. The voltage divider should be placed close to the FB pin to prevent noise pickup. Figure 3 shows the recommended PCB layout. The ISL9113A integrates one N-channel MOSFET and one P-channel MOSFET to realize a synchronous boost converter. In the 8 Ld DFN package, the heat generated in the device is mainly dissipated through the thermal pad. Maximizing the 5 FN8620.0 December 19, 2013 ISL9113A copper area connected to the thermal pad is preferable. It is recommended to add at least 4 vias within the pad to the GND plane for the best thermal relief. TABLE 1. INDUCTOR VENDOR INFORMATION MANUFACTURER PART NUMBER DIMENSIONS- W x L x H (mm) Murata LQH32PN2R2NN0L 3.2 x 2.5 x 1.7(max) Toko 1239AS-H-2R2M 2.5 x 2.0 x 1.2(max) 1286AS-H-2R2M 2.0 x 1.6 x 1.2(max) TDK TFM201610A-2R2M 2.0 x 1.6 x 1.0(max) Cyntec PSE25201B-2R2MS 2.0 x 1.6 x 1.2(max) Capacitor Selection INPUT CAPACITOR A minimum of a 4.7µF ceramic capacitor is recommended to provide stable operation under typical operating conditions. For input voltage less than 1.0V application, an additional 4.7µF ceramic capacitor is recommended for better noise filtering and EMI suppression. The input capacitor should be placed close to the input pin, GND pin, and the non-switching terminal of the inductor. OUTPUT CAPACITOR FIGURE 3. RECOMMENDED PCB LAYOUT Output Voltage Setting Resistor Selection Resistors R1 and R2, shown in the “Block Diagram” on page 2, can be used to set the desired output voltage values using Equation 1: R 1⎞ ⎛ V OUT = V FB • ⎜ 1 + -------⎟ R 2⎠ ⎝ For the output capacitor, a ceramic capacitor with small ESR is recommended to minimize output voltage ripple. A typical 4.7µF should be used to provide stable operation at different typical operating conditions. The output capacitor should be placed close to the output pin and GND pin of the device. Table 2 shows the recommended capacitors. (EQ. 1) where VFB is the internal FB reference voltage (0.8V typical). The current flowing through the divider resistors is calculated as VOUT /(R1 + R2). Large resistance is recommended to minimize current into the divider and thus improve the total efficiency of the converter. R1 and R2 should be placed close to the FB pin of the device to prevent noise pickup. TABLE 2. CAPACITOR VENDOR INFORMATION MANUFACTURER SERIES WEBSITE AVX X5R www.avx.com Murata X5R www.murata.com Taiyo Yuden X5R www.t-yuden.com TDK X5R www.tdk.com Inductor Selection TABLE 3. FAULT DETECTION AND RESPONSE An inductor with core material suitable for high frequency applications (e.g., ferrite) is desirable to minimize core loss and improve efficiency. The inductor should have a low ESR to reduce copper loss. Moreover, the inductor saturation current should be higher than the maximum peak current of the device; i.e., 1.5A. The device is designed to operate with an inductor value of 2.2µH to provide stable operation across the range of load, input and output voltages. Stable mode switching between PWM and skip mode operation is guaranteed at this inductor value. Table 1 shows recommended inductors. 6 FAULT CONDITION Low Battery Voltage DETECTION DETAILS VBAT < 0.7V VOUT out of Regulation VOUT is 10% below the target output voltage ACTION Shut down until VEN or VBAT is cycled. Shut down only if VBAT and VOUT fall below 2.1V. Device automatically restarts after 200ms. Short Circuit VOUT falls below VBAT Shut down immediately. Device automatically restarts after 200ms. Over-temperature Protection Die temperature is > Switching stops. Device +150°C automatically restarts when temperature decreases to +125°C. Output Overvoltage Protection VOUT > 5.9V Switching stops until EN pin is toggled or power is cycled. FN8620.0 December 19, 2013 ISL9113A Typical Characteristics 1.2 5.16 5.14 1.0 VOUT = 5.0V 0.8 VOUT = 4.0V VOUT (V) IOUT (A) ILOAD = 1mA (PFM) 5.12 0.6 0.4 5.10 ILOAD = 100mA (PWM) 5.08 5.06 0.2 5.04 0 0.8 1.3 1.8 2.3 2.8 3.3 VBAT (V) 3.8 4.3 4.8 5.02 0 2 3 4 5 VBAT (V) FIGURE 5. LINE REGULATION, VOUT = 5V FIGURE 4. MAXIMUM OUTPUT CURRENT vs INPUT VOLTAGE L = 2.2µH, COUT = 4.7μF 1 VBAT = 3.0V, VOUT = 5.0V, ILOAD = 20mA L = 2.2µH, COUT = 4.7μF VBAT = 3.0V, VOUT = 5.0V, ILOAD = 250mA VOUT WITH 5.0V OFFSET (50mV/DIV) VOUT WITH 5.0V OFFSET (200mV/DIV) INDUCTOR CURRENT(500mA/DIV) INDUCTOR CURRENT(500mA/DIV) SW (2V/DIV) TIME 10µs/DIV SW (2V/DIV) FIGURE 6. PULSE SKIP MODE WAVEFORM VBAT = 3.0V, VOUT = 5.0V, ILOAD = 250mA TIME 1µs/DIV FIGURE 7. PWM WAVEFORM VBAT = 3.0V, VOUT = 5.0V, ILOAD = 50mA EN EN (5V/DIV) VOUT (2V/DIV) VOUT (2V/DIV) INDUCTOR CURRENT(500mA/DIV) INDUCTOR CURRENT(500mA/DIV) SW(5V/DIV) SW(5V/DIV) TIME 40ms/DIV FIGURE 8. START-UP AFTER ENABLE (ILOAD = 250mA) 7 TIME 40ms/DIV FIGURE 9. START-UP AFTER ENABLE (ILOAD = 50mA) FN8620.0 December 19, 2013 ISL9113A Typical Characteristics (Continued) VBAT = 3.6V, VOUT = 5.0V VBAT = 3.6V, VOUT = 5.0V VOUT (100mV/DIV) VOUT (200mV/DIV) TBD INDUCTOR CURRENT(500mA/DIV) INDUCTOR CURRENT(500mA/DIV) ILOAD @ 0.66Ω (200mV/DIV) ILOAD @ 0.66Ω (200mV/DIV) TIME 400µs/DIV TIME 400µs/DIV FIGURE 10. LOAD TRANSIENT RESPONSE (100mA TO 500mA) FIGURE 11. LOAD TRANSIENT RESPONSE (20mA TO 250mA) 5.20 VOUT (V) 5.15 5.10 4.2V 3.0V 5.05 5.00 0 0.2 0.4 0.6 3.6V 0.8 1.0 ILOAD (A) FIGURE 12. LOAD REGULATION 8 FN8620.0 December 19, 2013 ISL9113A Revision History The revision history provided is for informational purposes only and is believed to be accurate, but not warranted. Please go to web to make sure you have the latest revision. DATE REVISION December 19, 2013 FN8620.0 CHANGE Initial Release. About Intersil Intersil Corporation is a leader in the design and manufacture of high-performance analog, mixed-signal and power management semiconductors. The company's products address some of the largest markets within the industrial and infrastructure, personal computing and high-end consumer markets. For more information about Intersil, visit our website at www.intersil.com. For the most updated datasheet, application notes, related documentation and related parts, please see the respective product information page found at www.intersil.com. You may report errors or suggestions for improving this datasheet by visiting www.intersil.com/en/support/ask-an-expert.html. Reliability reports are also available from our website at http://www.intersil.com/en/support/qualandreliability.html#reliability For additional products, see www.intersil.com/en/products.html Intersil products are manufactured, assembled and tested utilizing ISO9001 quality systems as noted in the quality certifications found at www.intersil.com/en/support/qualandreliability.html Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries 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 Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 9 FN8620.0 December 19, 2013 ISL9113A Package Outline Drawing L8.2x2D 8 LEAD DUAL FLAT NO-LEAD PLASTIC PACKAGE (DFN) WITH EXPOSED PAD Rev 0, 3/11 2.00 6 PIN 1 INDEX AREA 6 PIN #1 INDEX AREA A B 8 1 2.00 6x 0.50 (4X) 1.55±0.10 0.15 0.10M C A B 0.22 4 TOP VIEW ( 8x0.30 ) 0.90±0.10 0±0.10 0±0.10 BOTTOM VIEW SEE DETAIL "X" C 0.10 C 0.90±0.10 BASE PLANE 0 . 00 MIN. 0 . 05 MAX. SEATING PLANE 0.08 C SIDE VIEW 0 . 2 REF C DETAIL "X" ( 8x0.20 ) PACKAGE OUTLINE ( 8x0.30 ) NOTES: 1. Dimensions are in millimeters. Dimensions in ( ) for Reference Only. 2. Dimensioning and tolerancing conform to AMSE Y14.5m-1994. 3. Unless otherwise specified, tolerance: Decimal ± 0.05 4. Dimension applies to the metallized terminal and is measured ( 6x0.50 ) 1.55 2.00 between 0.15mm and 0.30mm from the terminal tip. ( 8x0.22 ) 0.90 2.00 TYPICAL RECOMMENDED LAND PATTERN 10 5. Tiebar shown (if present) is a non-functional feature. 6. The configuration of the pin #1 identifier is optional, but must be located within the zone indicated. The pin #1 identifier may be either a mold or mark feature. FN8620.0 December 19, 2013