FAN5601 Regulated Step-Down Charge Pump DC/DC Converter Features Description ■ > 85% Peak Efficiency ■ Low EMI ■ Low Ripple The FAN5601 is an advanced third generation switched capacitor step down DC/DC converter utilizing Fairchild’s proprietary ScalarPump™ technology. This innovative architecture utilizes scalar switch re-configuration and fractional switching techniques to produce low output ripple, low ESR spikes and improve efficiency over a wide load range. ■ ■ ■ ■ ■ Output Voltage 1.3V/1.8V Input Voltage Range: 2.2V to 5.5V Output Current: Up to 250mA ±2.5% Output Voltage Accuracy 30µA Operating Current The FAN5601 produces a fixed regulated output from 2.2V to 5V input voltage. Customized output voltages are available in 100mV increments from 1V to 1.8V. Contact marketing for customized outputs. ■ ICC < 1µA in Shutdown Mode ■ 2MHz Operating Frequency ■ Shutdown Isolates Output from Input In order to maximize efficiency, the FAN5601 achieves regulation by skipping pulses. Depending upon load current, the size of the switches is scaled dynamically, consequently, current spikes and EMI are minimized. An internal soft start circuitry prevents excessive current drawn from the supply. The device is internally protected against short circuit and over temperature conditions. ■ Soft-Start Limits Inrush Current ■ Short Circuit and Over Temperature Protection ■ Minimum External Component Count ■ 6-Lead 3x3mm MLP Package The FAN5601 is available in 6-lead 3x3mm MLP. Applications ScalarPump™ is a registered trademark of Fairchild Semiconductor Corporation. ■ Cell Phones ■ Handheld Computers ■ Portable Electronic Equipment ■ Core Supply to Next Generation Processors ■ Low Voltage DC Bus ■ Digital Cameras ■ DSP Supplies Typical Application CB = 1µF C+ FAN5601 INPUT 2.2V to 5.5V VIN CIN = 10µF CVOUT ENABLE GND ©2005 Fairchild Semiconductor Corporation FAN5601 Rev. 1.0.5 1 OUTPUT 1.0V t o 1.8V COUT = 10µF www.fairchildsemi.com FAN5601 Regulated Step-Down Charge Pump DC/DC Converter July 2005 FAN5601 Regulated Step-Down Charge Pump DC/DC Converter Pin Assignment FAN5601 Top-View C+ 1 6 VIN C- 2 5 VOUT ENABLE 3 4 GND 6-Lead 3x3mm MLP Pin Description Pin Name Pin No. 6-Lead 3x3mm MLP 1 C+ Bucket Capacitor Positive Connection Pin Function Description 2 C- Bucket Capacitor Negative Connection 3 ENABLE 4 GND Ground 5 VOUT Regulated Output Voltage. Bypass this pin with 10µF ceramic low ESR capacitor. 6 VIN Enable Pin Supply Voltage Input 2 FAN5601 Rev. 1.0.5 www.fairchildsemi.com Parameter Min Max Unit VIN,VOUT, ENABLE to GND -0.3 6.0 V C+, C-, to GND -0.3 VIN + 0.3 V VOUT Short Circuit Duration INDEFINITE Lead Soldering Temperature (10 seconds) Operating Temperature Range -40 Junction Temperature Storage Temperature -55 Electrostatic Discharge (ESD) Protection (Note2) HBM 4 CDM 1 300 °C +85 °C 150 °C 150 °C kV Recommended Operating Conditions Parameter Package Input Voltage Min Typ 2.2 Output Current Operating Ambient Temperature Thermal Resistance Junction to Tab Thermal Resistance Junction to Ambient -40 Max Unit 5.5 V 250 mA 85 °C 6-lead 3x3mm MLP 8 °C/W 6-lead 3x3mm MLP (Note 3) 90 °C/W Notes: 1. Operation beyond the absolute maximum rating may cause permanent damage to device. 2. Using Mil Std. 883E, method 3015.7(Human Body Model) and EIA/JESD22C101-A (Charge Device Model). 3. One square inch, 1oz bottom side GND plane connected to top side GND plane by field of via. 3 FAN5601 Rev. 1.0.5 www.fairchildsemi.com FAN5601 Regulated Step-Down Charge Pump DC/DC Converter Absolute Maximum Ratings (Note1) VIN = 2.2V to 5.5V, IOUT = 1mA, CB = 1µF, CIN = 10µF, COUT = 10µF, TA = -40°C to +85°C, typical values measured at TA = 25°C, unless otherwise noted. Parameter Conditions Input Undervoltage Lockout Min. 1.9 Output Voltage Output Voltage Accuracy Output Voltage Temperature Coefficient No load Supply Current (Note 4) Shutdown Supply Current Output Short-circuit Current (Note 5) Efficiency VIN at Configuration Change Max. Units 2.0 2.17 V Vnom V TA = 25°C, VIN = 3.3V -2 +2 % VIN = 3.3V -2.5 +2.5 % VIN = 3.3V 25 Load Regulation Line Regulation Typ. ppm 0.133 mV/mA TA = 25°C 1.35 2 mV/V IOUT = 0mA, VIN = 2.2V 30 60 µA ENABLE =GND. VOUT = 0 0.1 1 µA VOUT = GND. 25 mA VIN = 2.35 × VOUT IOUT =150mA 85 % From 2:1 to 1:1 mode 2.22 x Vnom V Oscillator Frequency 2.0 MHz Thermal Shutdown Threshold 150 °C °C Thermal Shutdown Threshold Hysteresis 15 ENABLE Logic Input High Voltage, VIH VIN = 2.2V to 5.5V ENABLE Logic Input Low Voltage, VIL VIN = 2.2V to 5.5V ENABLE Logic Input Current ENABLE = VIN or GND VOUT Turn On Time VIN = 3.6V, IOUT = 0mA, 10% to 90% 1.3 V 0.4 -1 1 1 V µA mS Notes: 4. No load supply current is measured when the oscillator is off. 5. The short circuit protection is designed to protect against pre-existing short circuit conditions, i.e. assembly shorts that exist prior to device power-up. The short circuit current limit is 25mAAverage. Short circuit currents in normal operation are inherently limited by the ON-resistance of internal device. Since this resistance is in the range of 1Ω, in some cases thermal shutdown may occur. However, immediately following the first thermal shutdown event, the short circuit condition will be treated as pre-existing, and the load current will reduce to 25mAAverage. 4 FAN5601 Rev. 1.0.5 www.fairchildsemi.com FAN5601 Regulated Step-Down Charge Pump DC/DC Converter Electrical Characteristics FAN5601 Regulated Step-Down Charge Pump DC/DC Converter Typical Performance Characteristics TA = 25°C, CIN = COUT =10µF, CB = 1µF, VOUT = 1.3V, unless otherwise noted. Load Transient Response VIN = 3.3V IOUT = 100mA Load Current (100mA/div) V IN = 2 V to 4.4V IOUT = 10mA V IN = 2V (20mV/div) Output Voltage (50mV/div) V IN = 4.4V (1V/div) Input Voltage Output Voltage Line Transient Response IOUT = 1mA Time (10µs/div) Time (1ms/div) Shutdown Current vs Input Voltage Input Current vs Input Voltage 70 46 Shutdown Current (nA) Input Current (µA) VOUT = 0V IOUT = 0mA 44 42 40 38 36 34 32 60 50 40 30 20 30 10 28 2.0 2.5 2.5 3.0 3.5 4.0 4.5 5.0 3.0 3.5 5.5 4.0 4.5 5.0 5.5 Input Voltage (V) Input Voltage (V) Mode Change Threshold and Hysteresis vs Load Current Output Voltage vs Ambient Temperature Threshold and Hysteresis (V) 1.31 Output Voltage (V) 1.30 VIN = 4V IOUT = 10mA 1.29 1.28 1.27 1.26 -60 -40 -20 0 20 40 60 80 3.0 2.5 High Threshold Low Threshold 2.0 1.5 Hysteresis 1.0 0.5 0.0 0 100 120 140 20 40 60 80 100 120 140 160 Load Current (mA) Ambient Temperature (°C) 5 FAN5601 Rev. 1.0.5 3.5 www.fairchildsemi.com FAN5601 Regulated Step-Down Charge Pump DC/DC Converter Typical Performance Characteristics (cont.) TA = 25°C, CIN = COUT =10µF, CB = 1µF, VOUT = 1.3V, unless otherwise noted. Enable Delay Enable Threshold vs Input Voltage Output Voltage (500m V/div) 1.3 IOUT = 10mA TA = 25°C 1.1 IOUT = 10mA VIN = 2.2V 1.0 0.9 Enable Voltage (5V/div) V En able (V) 1.2 0.8 0.7 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 V IN (V) Time (400 s/div) Output Ripple IOUT = 1.3µA VIN = 2.7V VOUT = 1.3V VOUT = 1.3V Output Ripple (10mV/div) IOUT = 1.3µA VIN = 2.2V Time (40ms/div) Time (40ms/div) Output Ripple Output Ripple IOUT = 1.3µA IOUT = 1.3µA VIN = 3.6V VIN = 4.2V VOUT = 1.3V VOUT = 1.3V Output Ripple (10mV/div) Output Ripple (2mV/div) Output Ripple (10mV/div) Output Ripple Time (20ms/div) Time (20ms/div) 6 FAN5601 Rev. 1.0.5 www.fairchildsemi.com FAN5601 Regulated Step-Down Charge Pump DC/DC Converter Typical Performance Characteristics (cont.) TA = 25°C, CIN = COUT =10µF, CB = 1µF, VOUT = 1.3V, unless otherwise noted. Output Ripple VOUT = 1.3V VOUT = 1.3V (10mV/div) IOUT = 10mA VIN = 2.2V Output Ripple IOUT = 1.3µA VIN = 5.5V (10mV/div) Time (20ms/div) Time (100µs/div) Output Ripple Output Ripple IOUT = 10mA VIN = 3.6V Output Ripple VOUT = 1.3V (10mV/div) IOUT = 10mA VIN = 2.7V VOUT = 1.3V Time (100µs/div) Time (100µs/div) Output Ripple Output Ripple IOUT = 10mA VIN = 5.5V VOUT = 1.3V Time (100µs/div) VOUT = 1.3V Time (100µs/div) 7 FAN5601 Rev. 1.0.5 (10mV/div) IOUT = 10mA VIN = 4.2V Output Ripple (10mV/div) Output Ripple Output Ripple (10mV/div) Output Ripple Output Ripple www.fairchildsemi.com FAN5601 Regulated Step-Down Charge Pump DC/DC Converter Typical Performance Characteristics (cont.) TA = 25°C, CIN= COUT =10µF, CB = 1µF, VOUT = 1.3V, unless otherwise noted. Output Ripple IOUT = 150mA VIN = 2.7V VOUT = 1.3V VOUT = 1.3V Output Ripple (20mV/div) IOUT = 150mA VIN = 2.2V Time (10µs/div) Time (10µs/div) Output Ripple Output Ripple IOUT = 150mA IOUT = 150mA VIN = 3.6V VIN = 4.2V VOUT = 1.3V VOUT = 1.3V Output Ripple (20mV/div) Output Ripple (20mV/div) Output Ripple (20mV/div) Output Ripple Time (1µs/div) Time (10µs/div) Output Ripple IOUT = 150mA Output Ripple (20mV/div) VIN = 5.5V VOUT = 1.3V Time (1µs/div) 8 FAN5601 Rev. 1.0.5 www.fairchildsemi.com FAN5601 Regulated Step-Down Charge Pump DC/DC Converter Typical Performance Characteristics (cont.) TA = 25°C, CIN= COUT =10µF, CB = 1µF, VOUT = 1.3V, unless otherwise noted. Output Voltage vs Input Voltage Efficiency vs Input Voltage 100 1.35 90 1.30 VOUT = 1.3V Efficiency (%) Ouput Voltage (V) 80 1.25 1.20 1.15 Load Current = 1mA Load Current = 10mA Load Current = 50mA Load Current = 100mA Load Current = 150mA Load Current = 250mA 1.10 1.05 1.00 TA = 25°C 70 60 50 40 Load Load Load Load Load Load 30 20 10 Current Current Current Current Current Current = = = = = = 0 0.95 1 2 3 4 5 1 6 2 3 4 5 6 Input Voltage (V) Input Voltage (V) Output Voltage vs Load Current Peak Efficiency vs Load Current 88 1.32 VIN = 4.5V VIN = 2.95V Peak Efficiency (%) 1.30 Ouput Voltage (V) 1mA 10mA 50mA 100mA 150mA 250mA 1.28 1.26 TA TA TA TA 1.24 1.22 = = = = -40°C 0°C 80°C 125°C TA = 25°C 86 84 82 80 1.20 78 0 50 100 150 200 250 300 0 Load Current (mA) 100 150 200 250 300 Load Current (mA) 9 FAN5601 Rev. 1.0.5 50 www.fairchildsemi.com V IN 0.25SW1 0.25SW1 0.5SW1 OSCILLATOR (2MHz) IN VOLTAGE REF. SOFT START Vref RAMP OUT Vref RAMP FB OUTPUT 150mV 0.5* INPUT 1V C+ - CONFIGURATION 0.25SW2 0.25SW2 0.5SW2 + - CONTROL LOGIC + - D R I V E R S PULSE_SKIP SHORT_CKT. 0.25SW3 0.25SW3 0.5SW3 0.25SW4 0.25SW4 0.5SW4 C- + - VOUT UVLO SHUTDOWN + THERMAL SHUTDOWN FB GND. ENABLE Detailed Description Pulse-skipping PFM and Fractional Switch Operation The FAN5601 switched capacitor DC/DC converter automatically configures switches to achieve a high efficiency and provides a regulated output voltage by means of pulse skipping, pulse frequency modulation (PFM). An internal soft start circuit prevents excessive inrush current drawn from the supply. Each switch is split into three segments. Based on the values of VIN, VOUT and IOUT, an internal circuitry determines the number of segments to be used to reduce current spikes. When the regulated output voltage reaches its upper limit, the switches are turned off the output voltage reaches its lower limit. Considering a step-down 2:1 mode of operation, 1.6V output as an example, when the output reaches about 1.62V(upper limit), the control logic turns off all switches. Switching stops completely. This is pulse-skipping mode. Since the supply is isolated from the output, the output voltage will drop. Once the output is dropped to about 1.58V(lower limit), the device will return to regular switching mode with one quarter of each switch turning on first. Another quarter of each switch will be turned on if VOUT cannot reach regulation by the time of arrival of the third charge cycle. Full switch operation occurs only during startup or under heavy load condition, when half switch operation cannot achieve regulation within seven charge cycles. Step-Down Charge Pump Operation When VIN ≥ 2.22 × VOUT, a 2:1 configuration shown in Fig.1(A) is enabled. The factor 0.9 is used instead of 1 in order to account for the effect of resistive losses across the switches and to accommodate hysteresis in the voltage detector comparator. Two phase non-overlapping clock signals are generated to drive four switches. When switches 1 and 3 are ON, switches 2 and 4 are OFF and CB is charged. When switches 2 and 4 are ON, switches 1 and 3 are OFF, charge is transferred from CB to COUT. Soft Start The soft-start feature limits inrush current when the device is initially powered up and enabled. The reference voltage is used to control the rate of the output voltage ramp-up to its final value. Typical start-up time is 1ms. Since the rate of the output voltage ramp-up is controlled by an internally generated slow ramp, pulse-skipping occurs and inrush current is automatically limited. When VIN <2.22 × VOUT , a 1:1 configuration shown in Fig. 1(B) is enabled. In the 1:1 configuration switch 3 is always OFF and the switch 4 is always ON. At 1.6V output setting the configuration changes from 2:1 to 1:1 at VIN = 3.56V. At 1.3V output setting the change occurs at VIN = 3.06V. 10 FAN5601 Rev. 1.0.5 www.fairchildsemi.com FAN5601 Regulated Step-Down Charge Pump DC/DC Converter Block Diagram connected from the output. UVLO triggers when supply voltage drops below 2V. When the output voltage is lower than 150mV, a short circuit protection is triggered. In this mode 15 out of 16 pulses during the switching will be skipped and the supply current is limited. Thermal shutdown triggers at 150°C. The device has an active-low shutdown pin to decrease supply current to less than 1µA. In shutdown mode the supply is dis- Switch Configuration VIN VIN S1 S1 C+ C+ S2 S2 C B VOUT VOUT C B S3 S3 C- CC OUT C S4 OUT S4 GND GND Figure 2. (A) Figure 2. (B) 1:1 configuration Switch 3 is always off and Switch 4 is always on Switches 1 and 2 are in phase 1 Reverse the position of switches 1&2 for phase 2 2:1 configuration Switches in charging phase Reverse all switches for pumping phase Applications Information The value of the bucket capacitor is dependent on load current requirements. A 1µF bucket capacitor will work well in all applications at all load currents, while a 0.1µF capacitor will support most applications under 100mA of load current. The choice of bucket capacitor values should be verified in the actual application at the lowest input voltage and highest load current. A 30% margin of safety is recommended in order to account for the tolerance of the bucket capacitor and the variations in the on-resistance of the internal switches. Proper operation of the FAN5601 requires one ceramic bucket capacitor in the 0.1µF to 1µF range; one 10µF output bypass capacitor and one 10µF input bypass capacitor. In order to obtain optimum output ripple and noise performance, use of low ESR (<0.05Ω) ceramic input and output bypass capacitors is recommended. The X5R and X7R rated capacitors provide adequate performance over the -40°C to 85°C temperature range. 11 FAN5601 Rev. 1.0.5 www.fairchildsemi.com FAN5601 Regulated Step-Down Charge Pump DC/DC Converter Shutdown, UVLO, Short Circuit Current Limit and Thermal Shutdown In applications where conductive and radiated EMI/RFI interference has to be kept as low as possible, the user may consider the use of additional input and output filtering. For example, adding an L-C filter to the standard output bypass configuration is very effective in reducing both the output ripple and the voltage spikes. Figure 2 shows an L-C filter using a 100nH chip inductor and a 1µF capacitor. The channel 1 of Figure 3 shows the ripple voltage at the output of the device while Channel 2 shows the ripple voltage at the output of the filter at VIN = 3.3V, (10mV/div) Output Ripple VOUT = 1.3V and IOUT = 100mA. Similar filtering method will greatly reduce the current spikes at the input. The user should be mindful of considering resistive voltage drops in the inductors connected serially in the input and output leads. IOUT = 100mA VIN = 3.3V (10mV/div) Ripple at CF VOUT = 1.3V CB = 1µF Time (10µs/div) VIN CIN = 10µF C– FAN5601 INPUT 2.2V to 5.5V C+ LF = 100nH Output 1.0V to 1.8V Figure 2. Effect of L-C Filter on output ripple VOUT CF = 1µF While evaluating the FAN5601 (or any other switched capacitor DC-DC converter) the user should be careful to keep the power supply source impedance low; use of long wires causing high lead inductances and resistive losses should be avoided. A carefully laid out ground plane is essential because current spikes are generated as the bucket capacitor is charged and discharged. The input and output bypass capacitors should be placed as close to the device pins as possible. COUT = 10µF ENABLE GND Figure 1. Optional L-C Filter 12 FAN5601 Rev. 1.0.5 www.fairchildsemi.com FAN5601 Regulated Step-Down Charge Pump DC/DC Converter One of the key benefits of the ScalarPump™ architecture is that the dynamically scaled on-resistance of the switches effectively reduces the peak current in the bucket capacitor and therefore input and output ripple current is also reduced. Nevertheless, due to the ESR of the input and output bypass capacitors, these current spikes generate voltage spikes at the input and output pins. However, these ESR spikes can be easily filtered because their frequency lie at up to 12 times the clock frequency. 6-Lead 3x3mm MLP Package 2.45 0.15 3.0 C 2X 1.65 2.10 3.50 3.0 (0.70) 0.15 C 0.95 TYP 0.65 TYP 2X TOP VIEW RECOMMENDED LAND PATTERN 0.8 MAX 0.10 C (0.20) 0.08 C 0.05 0.00 SIDE VIEW SEATING PLANE 2.25 PIN #1 IDENT 3 1 0.45 0.20 1.65 0.2 MIN 4 6 0.95 1.90 0.30~0.45 0.10 0.05 C A B C BOTTOM VIEW NOTES: A. CONFORMS TO JEDEC REGISTRATION MO-229, VARIATION WEEA, DATED 11/2001 B. DIMENSIONS ARE IN MILLIMETERS. C. DIMENSIONS AND TOLERANCES PER ASME Y14.5M, 1994 13 FAN5601 Rev. 1.0.5 www.fairchildsemi.com FAN5601 Regulated Step-Down Charge Pump DC/DC Converter Mechanical Dimensions Product Number Package Type Voltage Option [Vnom] Order Code FAN5601 6-Lead 3x3mm MLP 1.3V FAN5601MP13X 6-Lead 3x3mm MLP 1.8V FAN5601MP18X 14 FAN5601 Rev. 1.0.5 www.fairchildsemi.com FAN5601 Regulated Step-Down Charge Pump DC/DC Converter Ordering Information The following are registered and unregistered trademarks Fairchild Semiconductor owns or is authorized to use and is not intended to be an exhaustive list of all such trademarks. ACEx™ FAST ActiveArray™ FASTr™ Bottomless™ FPS™ Build it Now™ FRFET™ CoolFET™ GlobalOptoisolator™ CROSSVOLT™ GTO™ DOME™ HiSeC™ EcoSPARK™ I2C™ E2CMOS™ i-Lo™ EnSigna™ ImpliedDisconnect™ FACT™ IntelliMAX™ FACT Quiet Series™ Across the board. Around the world.™ The Power Franchise Programmable Active Droop™ ISOPLANAR™ LittleFET™ MICROCOUPLER™ MicroFET™ MicroPak™ MICROWIRE™ MSX™ MSXPro™ OCX™ OCXPro™ OPTOLOGIC OPTOPLANAR™ PACMAN™ POP™ Power247™ PowerEdge™ PowerSaver™ PowerTrench QFET SuperSOT™-8 SyncFET™ TinyLogic QS™ QT Optoelectronics™ Quiet Series™ RapidConfigure™ RapidConnect™ µSerDes™ SILENT SWITCHER SMART START™ SPM™ Stealth™ SuperFET™ SuperSOT™-3 SuperSOT™-6 TINYOPTO™ TruTranslation™ UHC™ UltraFET UniFET™ VCX™ Wire™ DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. 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PRODUCT STATUS DEFINITIONS Definition of Terms Datasheet Identification Product Status Definition Advance Information Formative or In Design This datasheet contains the design specifications for product development. Specifications may change in any manner without notice. Preliminary First Production This datasheet contains preliminary data, and supplementary data will be published at a later date. Fairchild Semiconductor reserves the right to make changes at any time without notice in order to improve design. No Identification Needed Full Production This datasheet contains final specifications. Fairchild Semiconductor reserves the right to make changes at any time without notice in order to improve design. Obsolete Not In Production This datasheet contains specifications on a product that has been discontinued by Fairchild semiconductor. The datasheet is printed for reference information only. Rev. I16 15 FAN5601 Rev. 1.0.5 www.fairchildsemi.com FAN5601 Regulated Step-Down Charge Pump DC/DC Converter TRADEMARKS