AP6015 High Efficiency Step-Down Low Power DC-DC Converter General Description Features * * * * * * * * * * * * High efficiency synchronous step-down converter with greater than 94% Current Mode Operation for faster transient response and better loop stabilization 2.5V to 5.5V operating input voltage range Adjustable output voltage range from 0.8V to VIN Fixed output voltage options: 1.8V, 2.5V and 3.3V Up to 800mA output current High efficiency over a wide range of load currents PWM operation mode Internal soft-start function Typical quiescent current of 150A MSOP-10L: Available in "Green" Molding Compound (No Br, Sb) Lead Free Finish/ RoHS Compliant (Note 1) The AP6015 is the first device in a family of low-noise current mode synchronous step-down DC-DC converters. It is ideally suited for systems powered by either a 1-cell Li-ion battery or a 2to 3-cell NiCd/ NiMH/ Alkaline battery. The AP6015 is a synchronous PWM converter with integrated N- and P-channel power MOSFET switches. Compared to the asynchronous topology, synchronous rectification offers the benefits of higher efficiency and reduced component count. The high operating frequency of 1MHz allows small inductor and capacitor to be used. This results in small pcb area. During shut-down, the standby current drops to 1A or less. The AP6015 is available in the 10-pin MSOP package. It operates o o over a free-air temperature range of -40 C to 85 C. Applications * * * * * Mobile Handsets PDAs, Ultra Mobile PCs Portable Media Players, Digital Still/Video Cameras USB-based DSL Modems LAN/WLAN/WPAN/WWAN Modules Ordering Information AP 6015 - XX M10 G - 13 Voltage Package Green Packing Blank : Adj 18 : 1.8V 25 : 2.5V 33 : 3.3V M10 : MSOP-10L G : Green 13 : Tape & Reel Device AP6015-XXM10G-13 Notes: Package Code M10 Packaging (Note 2) MSOP-10L 13" Tape and Reel Quantity Part Number Suffix 2500/Tape & Reel -13 1. EU Directive 2002/95/EC (RoHS). All applicable RoHS exemptions applied, see EU Directive 2002/95/EC Annex Notes. 2. Pad layout as shown on Diodes Inc. suggested pad layout document AP02001, which can be found on our website at http://www.diodes.com/datasheets/ap02001.pdf. AP6015 Rev. 3 1 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter Pin Assignment ( Top View ) PVCC 1 10 PGND LX VCC 2 9 GND 3 8 EN PG 4 7 FB/Vout 5 NC 6 CC MSOP-10L Pin Descriptions Pin Name Pin NO. I/O PVCC 1 I Description Supply voltage input Supply bypass pin. A 1F coupling capacitor should be connected as close as possible to this pin. VCC 2 GND 3 Ground PG 4 O Power good comparator output. A pull-up resistor should be connected between PG and VO. FB 5 I Feedback pin for the fixed output voltage option. CC 6 I Compensation pin NC 7 NC EN 8 I LX 9 I/O PGND 10 AP6015 Rev. 3 No connect Enable.Pin, H: Enable. L:shutdown Connect the inductor to this pin. Power ground 2 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter Block Diagram CC CC VCC UVLO TS SS EN CE PG PG Bias Open drain Vref=0.8V ER-AMP + FB FB PG_COM Current Protection + PVCC PVCC + PWM-COM - BANDGAP Osc Vramp LX Buffer - GND PGND PGND Notes: 3. The adjustable output voltage version does not use the internal feedback resistor divider. The FB pin is directly connected to the error amplifier. Absolute Maximum Ratings Symbol ESD HBM ESD MM PVCC, VCC TJ(MAX) TST TOP Parameter Human Body Model ESD Protection Machine Model ESD Protection Supply Voltage Voltages on pins EN, CC, PG, FB, LX Maximum Junction Temperature Range Storage temperature range Operating Junction Temperature Range Rating 2.5 300 -0.3 to +5.5 -0.3 to VIN +0.3 +150 -65 to +150 -40 to +125 Unit KV V V V o C o C o C Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods ma affect device reliability. AP6015 Rev. 3 3 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter Recommended Operating Conditions Symbol TA VIN VO L Ci Co Notes: (TA :-40~85C) Parameter Operating Ambient Temperature Range Supply Voltage Output voltage range for adjustable output voltage version Inductor (see Note 4) Input capacitor (see Note 4) Output capacitor (see Note 4) VO 1.8V Rating -40 to +85 2.0 to 5.5 0.8 to VI 3.3 10 10 Unit o C V V H F F 4. Refer to application section for further information. Electrical Characteristics (TA =25C) Over recommended operating free-air temperature range, VI=3.6V, VO=2.5V, IO=300mA, EN=VIN. (unless otherwise noted) Symbol Parameter Conditions Min Typ. Max IO= 0mA to 800mA 2.5 - 5.5 IO= 0mA to 500mA 2 - 5.5 IO= 0mA to 600mA 2.5 IO= 0mA to 400mA 2 - - Unit Supply current o -20 to 85 C VIN Input Voltage range o -40 to 85 C 5.5 V Iccq Operating quiescent current IO= 0mA - 150 - A ISTBY Standby current EN= GND - 0.1 1 A VIN 3V 1.5 - - VIN> 3V 2.5 - - - - 0.7 V - 0.01 0.1 A 1.2 1.6 1.95 V Enable VIH EN high-level input voltage VIL EN low-level input voltage IL EN input leakage current V(UVLO) EN= GND or VIN Under-voltage-lockout-threshold AP6015 Rev. 3 4 of 18 www.diodes.com V FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter Electrical Characteristics (Continued) Over recommended operating free-air temperature range, VI=3.6V, VO=2.5V, IO=300 mA, EN=VIN. (unless otherwise noted) Symbol Parameter Power switch and current limit Conditions VI=VGS=3.6V; I=200mA VI=VGS=2V; I=200mA P-channel leakage current VDS=5.5V RDS(on) VI=VGS=3.6V; IO=200mA N-channel MOSFET on-resistance VI=VGS=2V; IO=200mA N-channel leakage current VDS=5.5V I(LIM) P-channel current limit 2.5VVI5.5V Power good output (see Note 5) P-channel MOSFET on-resistance V(PG) Power good threshold Feedback voltage falling Min Typ. Max 200 200 1200 280 480 280 500 - 410 1 410 1 1600 88% VO Power good hysteresis VOL PG output low voltage ILKG PG output leakage current Minimum supply voltage for valid power good signal Oscillator FS Oscillator frequency Output VO Adjustable output voltage range VREF Reference voltage AP6015-Adj AP6015-1.8V VO Fixed output voltage (see Note 6) AP6015-2.5V AP6015-3.3V Line regulation Load regulation Efficiency Start-up time JA JC Notes: Thermal Resistance Junction-to-Ambient Thermal Resistance Junction-to-Case V(FB)=0.8xVO nominal; I(sink)=10A V(FB)=VO nominal - Unit m A m A mA 92% 94% VO VO 2.5% VO V - 0.3 V 0.01 1 A 1.2 - - V 800 1000 1200 KHz 0.8 0.784 0.8 5.5 0.816 V V VI=2.5V to 5.5V; 0mA IO 800mA 3% - 4% 10mA IO 800mA VI=2.7V to 5.5V; 0mA IO 800mA 10mA IO 800mA VI=3.6V to 5.5V; 0mA IO 800mA 10mA IO 800mA VI= VO 0.5V (min.2V) to 6.0V; IO=10mA VI=5.0V; IO=10mA to 800mA VI=5V; VO=3.3V; IO=300mA VI=3.6V; VO=2.5V; IO=200mA IO=0mA, time from active EN to VO 3% - 3% 3% - 4% 3% - 3% 3% - 4% 3% - 3% 0.4 V 0.3 %/V 0.8 % 94 % 1 4 ms MSOP-10L (Note 7) 161 o C/W MSOP-10L (Note 7) 39 o C/W 5. Power good is not valid for the first 100s after EN goes high. Please refer to the application section for more information. 6. The output voltage accuracy includes line and load regulation over the full temperature range. 7. Test condition for MSOP-10L: Device mounted on 2oz copper, minimum recommended pad layout on top & bottom layer with thermal vias, double sided FR-4 PCB AP6015 Rev. 3 5 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter Typical Application Circuit For best transient response we suggest that RCC, CCC and L1 values as below. RCC CCC L1-WURTH VIN < 3.0V, VOUT < 2.5V 200K 33PF 1.8H 68K 100PF 1.8H VIN 3.0V, VOUT < 2.5V 82K 100PF 3.3H VIN 3.0V, VOUT 2.5V C1, C2 (MLCC) 10F 10F 10F (1) ADJ Output VI 3.0 V to 5.5 V 1 PVCC LX 9 VCC FB 5 PG 4 L1 VO 2.5 V/800 mA 100 Ohm 2 8 AP6015 EN C1 10F C3 1F R3 680K R1 Power Good PGND 10 CC 6 Rcc GND 3 C2 10F R2 C CC 100pF R2: Suggest to be 39K~100K because of stability reasons. VO = VREF x (1 + R1 ) R2 Typical Application Circuit for Adjustable Output Voltage Option (2) FIXED Output Typical Application 1 PVCC VI 5 V LX 9 L1 VO 1.8/ 2.5/ 3.3V/ 800mA 100 Ohm 2 C1 10uF 8 VCC FB AP6015 EN C3 1uF GND 3 PG 5 4 R3 680K Power Good C2 10uF PGND 10 CC 6 Rcc CCC 100pF Standard 5 V to 1.8/ 2.5/ 3.3V/ 800mA Conversion; High Efficiency AP6015 Rev. 3 6 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter Typical Operating Characteristics Supply Current vs. Tem perature (Vcc=3.6V Vout=2.5V) 250 250 200 200 Supply Current (uA) Supply Current (uA) Input Voltage vs. Supply Current 150 100 50 150 100 50 Vout=0.8V Vout=1.8V 0 2 2.5 3 3.6 4 4.5 5 0 -40 5.5 -25 Input Voltage (V) 50 Figure 1 Figure 2 Stand-by Current vs. Input Voltage Stand-by Current vs. Tem perature (Vcc=3.6V) 85 1.2 0.1 1 0.08 Stand-by Current (uA) Stand-by Current (uA) 0 25 Tem perature ( ) 0.06 0.04 0.02 0.8 0.6 0.4 0.2 0 0 2 2.5 3 3.6 4 4.5 5 5.5 Input Voltage (V) -25 0 25 50 85 Tem perature () Figure 3 AP6015 Rev. 3 -40 Figure 4 7 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter Typical Operating Characteristics (Continued) Load Regulation (Vcc=5.0V Vout=2.5V) 2.55 2.55 2.54 2.54 2.53 2.53 Output Voltage (V) Output Voltage (V) Line Regulation (Vout=2.5V Iout=10m A) 2.52 2.51 2.5 2.49 2.48 2.52 2.51 2.5 2.49 2.48 2.47 2.47 2.46 2.46 2.45 3.0V 2.45 3.6 4 4.5 5 10 5.5 100 Input Voltage (V) Figure 5 800 Figure 6 Frequency vs. Tem perature (Vcc=3.6V Vout=2.5V) UVLO vs. Tem perature 1050 1.8 1000 1.72 950 1.64 UVLO (V) Frequency (KHz) 200 400 600 Output Current (m A) 900 1.56 850 1.48 800 750 -40 -25 0 25 50 85 1.4 -40 Temperature () 0 25 50 85 Tem perature ( ) Figure 7 AP6015 Rev. 3 -25 Figure 8 8 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter Typical Operating Characteristics (Continued) Efficiency vs. Load Current (Vcc=3.6V Vout=2.5V) 100 100 90 90 80 80 70 70 Efficiency (%) Efficiency (%) Efficiency vs. Load Current (Vcc=3.6V Vout=1.8V) 60 50 40 30 60 50 40 30 20 20 10 10 0 0 0 100 200 300 400 500 600 700 800 Load Current (mA) 100 200 300 400 500 600 700 800 Load Current (m A) Figure 9 Figure 10 Efficiency vs. Load Current (Vcc=5.0V Vout=2.5V) Efficiency vs. Load Current (Vcc=5.0V Vout=3.3V) 100 100 90 90 80 80 70 70 Efficiency (%) Efficiency (%) 0 60 50 40 30 60 50 40 30 20 20 10 10 0 0 0 100 200 300 400 500 600 700 800 Figure 11 AP6015 Rev. 3 0 100 200 300 400 500 600 700 800 Load Current (mA) Load Current (m A) Figure 12 9 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter Typical Operating Characteristics (Continued) Dropout Voltage vs. Load Current (Vout=3.3V) 400 400 350 350 Dropout Voltage (mV) Dropout Voltage (mV) Dropout Voltage vs. Load Current (Vout=2.5V) 300 250 200 150 100 50 300 250 200 150 100 50 0 0 0 100 200 300 400 500 600 700 800 Load Current (mA) AP6015 Rev. 3 0 100 200 300 400 500 600 700 800 Load Current (mA) Figure 13 Figure 14 Output Ripple Output Ripple Figure 15 Figure 16 10 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter Typical Operating Characteristics (Continued) Load Transient Response Load Transient Response Figure 17 Figure 18 Load Transient Response Load Transient Response Figure 19 Figure 20 AP6015 Rev. 3 11 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter Application Information Enable (EN) When EN is on logic low, the AP6015 goes into shutdown mode. In shutdown, all other functions are turned off. The supply current is reduced to 1uA (Typ.). Soft Start As the enable pin goes high, the soft-start function generates an internal voltage ramp. This causes the start-up current to slowly raise preventing output voltage overshoot and high inrush currents. The soft-start duration is typical 1mSec. AP6015 START-UP TIME Under Voltage Lock Out (UVLO) The UVLO prevents the converter from turning on when the voltage on VCC is less than typically 1.6V. 3.6V Vcc 1.6V UVLO 0V 2.5V Vout 0V AP6015 Rev. 3 12 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter Application Information Power Good (Continued) (PG) The PG comparator has an open drain output capable of sinking typically 10mA. The PG is only active when the AP6015 is enable (EN=high). When the AP6015 is disable (EN=low), the PG pin is high impedance. If the PG pin is connected to the output of the AP6015 with a pull-up resistor, no initial spike occurs and precautions have to be taken during start-up. The PG pin becomes active high when the output voltage exceeds typically 92% of its nominal value. Leave the PG pin unconnected when not used. PG Sink Current vs. ExteranI Voltage PG Sink Current (mA) 25 20 15 10 5 0 2 2.5 3 3.6 4 4.5 5 5.5 External Voltage (V) AP6015 Rev. 3 13 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter Application Information (Continued) Inductor Selection In order to avoid saturation of the inductor, the inductor should be rated at least for the maximum output current plus the inductor ripple current which is calculated as: VO ) VCC I L = VO x Lx f 1- ( I L ( MAX ) = I O ( MAX ) + I L 2 Where: f= Switching frequency (1MHz typical) L = Inductor value IL = Peak-to-peak inductor ripple current IL(max) = Maximum inductor current Vcc=3.6V Vout=2.5V f=1MHz IIL230mA AP6015 Rev. 3 L=3.3uH Vcc=3.6V Vout=2.5V f=1MHz L=1.8uH IIL360mA 14 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter Application Information (Continued) Input Capacitor Selection Though there is no special requirement for the ESR (Equivalent Series Resistance) of the input capacitor, due attention should be paid to the tolerance and temperature coefficient of the capacitor used. A 10uF or larger capacitance is required between the PVCC and the GND pins. The input capacitor should be placed as close as possible to the PVCC pin in order to achieve good overall system performance. Output Capacitor Selection Ripple at the voltage output pin is caused by the charge-and-discharge of the output capacitor. For the best performance, a low ESR output capacitor should be used. The equation below demonstrates how the size of the ripple can be calculated. VO ) VCC 1 1 x( + ESR) = I L x ( + ESR) VO = VO x Lx f 8 x CO x f 8 x CO x f 1- ( Where: Vo= Output voltage ripple L = Inductor value f = Switching frequency (1MHz typical) IL = Peak-to-peak inductor ripple current AP6015 Rev. 3 15 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter Application Information (Continued) Layout Considerations A good board layout practice can significantly improve the stability of the application circuit and reduce the system noise. The feedback path must be as short as possible. The input capacitor and bypass capacitor must be placed close to the PVCC and the VCC pins for optimal performance. It is recommended that the ground planes for System Ground / Power Ground / Analog Ground are isolated from each others, while they should all be joined together at a common point. An example drawing of a circuit with good ground noise performance is shown below. 1 VI LX PVCC 9 L1 VO 100 Ohm 2 C1 10F C3 1F 8 EN 10 FB 5 VCC AP6015 R3 680K R1 PG 4 PGND GND CC 3 6 Power Good C2 10 uF R2 Rcc C CC 100 pF The external inductor must be placed as close as possible to the switching node, i.e. the LX pin. The copper traces on the pcb, where high peak switching current may flow through, should be kept `wide' and `short'. This results in low inductance and capacitance in the current path, hence ground shift problem is avoided and system stability stay within bound. AP6015 Rev. 3 16 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter Marking Information ( Top View ) 9 10 8 Logo 7 6 A~Z : Green Y : Year : 0~9 W : Week : A~Z : 1~26 week; a~z : 27~52 week; z represents 52 and 53 week YWX 6015XX Part Number XX : 18 for 1.8V 25 for 2.5V 33 for 3.3V Blank for ADJ 2 1 3 4 5 MSOP-10L Package Information (All Dimensions in mm) (1) Package type: MSOP-10L 10x-0.30 4.4 4.8/5.0 2.95/3.05 1 1 0.75/0.95 1.10Max. 0.5Typ. Seting plane C Gauge plane 0.4/0.7 AP6015 Rev. 3 "A" 0.25 C 1 Land Pattern Recommendation (Unit:mm) 0 / 8 0.10 2.95/3.05 0.05/0.15 0.1/0.2 0.17/0.27 10x-1.4 8x-0.50 DETAIL "A" 17 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated AP6015 High Efficiency Step-Down Low Power DC-DC Converter IMPORTANT NOTICE Diodes Incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or other changes without further notice to any product herein. Diodes Incorporated does not assume any liability arising out of the application or use of any product described herein; neither does it convey any license under its patent rights, nor the rights of others. The user of products in such applications shall assume all risks of such use and will agree to hold Diodes Incorporated and all the companies whose products are represented on our website, harmless against all damages. LIFE SUPPORT Diodes Incorporated products are not authorized for use as critical components in life support devices or systems without the expressed written approval of the President of Diodes Incorporated. AP6015 Rev. 3 18 of 18 www.diodes.com FEBRUARY 2009 (c) Diodes Incorporated