ACT4528 Rev 2, 06-Jan-2016 40V/3.0A CV/CC Buck Converter Featuring QC2.0 and USB Auto-Detect GENERAL DESCRIPTION FEATURES ACT4528 is a wide input voltage, high efficiency step-down DC/DC converter that operates in either CV (Constant Output Voltage) mode or CC (Constant Output Current) mode. ACT4528 has QC2.0 decoding built in to provide 5.1V/9.1V/12.1V outputs as requested by attached portable devices. It also supports Apple 2.4A, Samsung and BC1.2 devices to charge at full current rate. 40V Input Voltage Surge 4.5V-36V Operational Input Voltage 5.1V/9.1V/12.1V Output with +/-1% Accuracy Up to 3.0A Output current Constant Current Regulation Limit QC2.0 Decoding + USB Auto-Detect Support Apple 2.4A, Samsung and BC1.2 Hiccup Mode Protection at Output Short >90% Efficiency at Full Load 0.5mA Low Standby Input Current 5.7V/10.1V/13.5V Output Over-voltage Protection for 5.1V/9.1V/12.1V Outputs Cord Voltage Compensation Meet EN55022 Class B Radiated EMI Standard 8kV ESD HBM Protection on DP and DM SOP-8EP Package ACT4528 has accurate output current limits under constant current regulation to meet MFi specification. It can provide up to 3.0A output current at 125kHz switching frequency. ACT4528 utilizes adaptive drive technique to achieve good EMI performance while main >90% efficiency at full load for mini size CLA designs. ACT4528 also has output short circuit protection with hiccup mode. The average output current is reduced to below 6mA when output is shorted to ground. Other features include output over voltage protection and thermal shutdown. APPLICATIONS Car Charger Cigarette Lighter Adaptor (CLA) Rechargeable Portable Device CV/CC regulation DC/DC converter ACT4528 is available in a SOP-8EP package and require very few external components for operation. Typical Application Circuit CSN 4.5V to 40V C3 22nF HSB SW IN CSP C2 10ìF GND DP 5V/9V/12V L1 47ìH ACT4528 C1 47ìF Rcs 25mÙ Vout C4 C5 22ìF 220ìF DM D1 SK54L C6 2.2ìF DD+ GND Vout 12.1V V/I Profile 9.1V 5.1V 3.2V 2.65A Innovative PowerTM -1- Iout www.active-semi.com Copyright © 2015-2017 Active-Semi, Inc. ACT4528 Rev 2, 06-Jan-2016 ORDERING INFORMATION PART NUMBER OPERATION TEMPERATURE RANGE PACKAGE FREQUENCY PACKING ACT4528YH-T -40°C to 85°C SOP-8EP 125kHz TAPE & REEL PIN CONFIGURATION CSP 1 8 HSB CSN 2 7 SW 6 IN 5 DM ACT4528 NC 3 DP 4 GND EP SOP-8EP Top View Innovative PowerTM -2- www.active-semi.com Copyright © 2015-2017 Active-Semi, Inc. ACT4528 Rev 2, 06-Jan-2016 PIN DESCRIPTIONS PIN NAME DESCRIPTION 1 CSP Voltage Feedback Input. Connect to node of the inductor and output capacitor. CSP and CSN Kevin sense is recommended. 2 CSN Negative input terminal of output current sense. Connect to the negative terminal of current sense resistor. 3 NC Not connected. 4 DP Data Line Positive Input. Connected to D+ of attached portable device data line. This pin passes 8kV HBM ESD. 5 DM Data Line Negative Input. Connected to D- of attached portable device data line. This pin passes 8kV HBM ESD. 6 IN Power Supply Input. Bypass this pin with a 10ìF ceramic capacitor to GND, placed as close to the IC as possible. 7 SW Power Switching Output to External Inductor. 8 HSB High Side Bias Pin. This provides power to the internal high-side MOSFET gate driver. Connect a 22nF capacitor from HSB pin to SW pin. 9 GND Ground and Heat Dissipation Pad. Connect this exposed pad to large ground copper area with copper and vias. ABSOLUTE MAXIMUM RATINGS PARAMETER VALUE UNIT -0.3 to 40 V SW to GND -1 to VIN +1 V HSB to GND VSW - 0.3 to VSW + 7 V CSP, CSN to GND -0.3 to +15 V All other pins to GND -0.3 to +6 V 46 °C/W Operating Junction Temperature -40 to 150 °C Storage Junction Temperature -55 to 150 °C 300 °C IN to GND Junction to Ambient Thermal Resistance Lead Temperature (Soldering 10 sec.) : Do not exceed these limits to prevent damage to the device. Exposure to absolute maximum rating conditions for long periods may affect device reliability. Innovative PowerTM -3- www.active-semi.com Copyright © 2015-2017 Active-Semi, Inc. ACT4528 Rev 2, 06-Jan-2016 ELECTRICAL CHARACTERISTICS (VIN = 12V, TA = 25°C, unless otherwise specified.) Parameter Input Over Voltage Protection Symbol VIN_OVP Condition Rising Min Typ Max Units 40 42 44 V Input Over Voltage Hysteresis Input Over Voltage Response Time Input Under Voltage Lockout (UVLO) T_VIN_OVP VIN step from 30V to 45V VIN Rising Input UVLO Hysteresis 4 V 250 ns 4.5 V 200 mV Input Voltage Power Good Deglitch Time No OVP 40 ms Input Voltage Power Good Deglitch Time No UVP 10 us Input Standby Current Vin=12V, Vout=5.1V, Iload=0 500 uA Output Voltage Regulation CSP 5.05 5.1 5.15 9.0 9.1 9.2 11.95 12.1 12.25 V 5.7 Output Over Voltage Protection (OVP) Output rising 10.1 V 13.5 Output Over Voltage Deglitch Time 1.0 Output Voltage Cord Compensation Output current 2.4A -15% 200 +15% mV -10% 3.2 10% V Output Under Voltage Protection (UVP) VOUT VOUT falling UVP Hysteresis VOUT VOUT rising UVP Deglitch Time VOUT UVP Blanking Time at Startup Output Constant Current Limit us Rcs=25mÙ 2.50 Hiccup Waiting Time 0.2 V 10 us 3.5 ms 2.65 2.80 A 4.13 S 5.8 A Top FET Rdson 70 mΩ Bottom FET Rdson 4.7 Ω Top FET Cycle by Cycle Current Limit 4.5 Maximum Duty Cycle 99 Switching Frequency -10% Soft-start Time Innovative PowerTM % 125 2.0 -4- +10% kHz ms www.active-semi.com Copyright © 2015-2017 Active-Semi, Inc. ACT4528 Rev 2, 06-Jan-2016 ELECTRICAL CHARACTERISTICS (VIN = 12V, TA = 25°C, unless otherwise specified.) Parameter Symbol Condition Min Typ Max Units Out Voltage Ripples Cout=470uF/22uF ceramic 80 mV VOUT Discharge Current For high to lower voltage transitions 60 mA Voltage transition time for QC 2.0 transition 12V-5V 100 ms Voltage transition time for QC 2.0 transition 5V-12V 100 ms Line Transient Response Input 12V-40V-12V with 1V/us slew rate, Vout=5V, Iload=0A and 2.4A 4.75 5.25 V Vout=5V 80mA-1.0A-80mA load with 0.1A/us slew rate 4.9 5.15 5.4 V Vout=9V 80mA-1.0A-80mA load with 8.7 9.1 9.5 V Vout=12V 80mA-1.0A-80mA load with 11.6 12.1 12.6 V Load Transient Response Thermal Shut Down 160 °C Thermal Shut Down Hysteresis 30 °C 8 kV ESD of DP, DM Innovative PowerTM HBM -5- www.active-semi.com Copyright © 2015-2017 Active-Semi, Inc. ACT4528 Rev 2, 06-Jan-2016 FUNCTIONAL BLOCK DIAGRAM HSB VIN UVLO PWM Controller 70mΩ USB Auto Detect QC2.0 Detect Driver SW 4.7Ω DP OVP Current Sense and Control DM CSP CSN GND FUNCTIONAL DESCRIPTION Output Under-Voltage Protection / Hiccup Mode Output Current Sensing and Regulation Sense resistor is connected to CSP and CSN. The sensed differential voltage is compared with interval reference to regulate current. CC loop and CV loop are in parallel. The current loop response is allowed to have slower response compared to voltage loop. However, during current transient response, the inductor current overshoot/undershoot should be controlled within +/-25% to avoid inductor saturation. There is a under voltage protection (UVP) threshold. If the UVP threshold is hit for 10us, an over current or short circuit is assumed, and the converter goes into hiccup mode by disabling the converter and restarts after hiccup waiting period. Cord Compensation The conventional cycle-by-cycle peak current mode is implemented with high-side FET current sense. In some applications, the increased with output current potential voltage drop across compensation is based on the resistance. Input Over Voltage Protection The compensation voltage is derived as: The converter is disabled if the input voltage is above 42V (+/-2V). Device resumes operation automatically 40ms after OVP is cleared. ÄVout = (VCSP-VCSN)*K Cycle-by-Cycle Current Control Where K=3.03 This voltage difference could be added on the reference or turning the (VCSP-VCSN) voltage into a sink current at FB pin to pull Vout higher than programmed voltage. Output Over Voltage Protection Device stops switching when output over-voltage is sensed, and resumes operation automatically when output voltage drops to OVP- hysteresis. The cord compensation loop should be very slow to avoid potential disturbance to the voltage loop. The voltage loop should be sufficiently stable on various cord compensation setting. Output Over Voltage Discharge Discharge circuit starts to discharge output through CSP pins when output over voltage is detected. Discharge circuit brings 12V down to 5V in less than 100ms. Innovative PowerTM output voltage is to compensate the output cable. The high side feedback Thermal Shutdown If the TJ increases beyond 160°C, ACT4528 goes into HZ mode and the timer is preserved until TJ drops by 30°C. -6- www.active-semi.com Copyright © 2015-2017 Active-Semi, Inc. ACT4528 Rev 2, 06-Jan-2016 APPLICATIONS INFORMATION recommended to parallel with tantalum or electrolytic capacitor, which should be placed right next to the IC. Inductor Selection The inductor maintains a continuous current to the output load. This inductor current has a ripple that is dependent on the inductance value. Output Capacitor Higher inductance reduces the peak-to-peak ripple current. The trade off for high inductance value is the increase in inductor core size and series resistance, and the reduction in current handling capability. In general, select an inductance value L based on ripple current requirement: L= VOUT × (VIN _VOUT ) VIN fSW ILOADMAX K RIPPLE The output capacitor also needs to have low ESR to keep low output voltage ripple. The output ripple voltage is: VRIPPLE I OUTMAX K RIPPLE RESR (1) Where VIN is the input voltage, VOUT is the output voltage, fSW is the switching frequency, ILOADMAX is the maximum load current, and KRIPPLE is the ripple factor. Typically, choose KRIPPLE = 30% to correspond to the peak-to-peak ripple current being 30% of the maximum load current. With a selected inductor value the peak-to-peak inductor current is estimated as: ILPK _ PK = VOUT × (VIN _VOUT ) L × VIN × fSW The peak inductor current is estimated as: 1 ILPK = ILOADMAX + ILPK PK 2 _ (2) (3) The selected inductor should not saturate at ILPK. The maximum output current is calculated as: 1 IOUTMAX = ILIM _ ILPK PK (4) 2 _ (VIN VOUT ) VOUT (5) 2 8 f SW LCOUT VIN Where IOUTMAX is the maximum output current, KRIPPLE is the ripple factor, RESR is the ESR of the output capacitor, fSW is the switching frequency, L is the inductor value, and COUT is the output capacitance. In the case of ceramic output capacitors, RESR is very small and does not contribute to the ripple. Therefore, a lower capacitance value can be used for ceramic type. In the case of tantalum or electrolytic capacitors, the ripple is dominated by RESR multiplied by the ripple current. In that case, the output capacitor is chosen to have sufficiently low ESR. For ceramic output capacitor, typically choose a capacitance of about 22µF. For tantalum or electrolytic capacitors, choose a capacitor with less than 50mÙ ESR. If an 330µF or 470µF electrolytic capacitor is used, where ripple is dominantly caused ESR, an 2.2uF ceramic in parallel is recommended. Rectifier Schottky Diode Use a Schottky diode as the rectifier to conduct current when the High-Side Power Switch is off. The Schottky diode must have current rating higher than the maximum output current and a reverse voltage rating higher than the maximum input voltage. Further more, the low forward voltage Schottky is preferable for high efficiency and smoothly operation. LLIM is the internal current limit. Input Capacitor The input capacitor needs to be carefully selected to maintain sufficiently low ripple at the supply input of the converter. A low ESR capacitor is highly recommended. Since large current flows in and out of this capacitor during switching, its ESR also affects efficiency. The input capacitance needs to be higher than 10µF. The best choice is the ceramic type. However, low ESR tantalum or electrolytic types may also be used provided that the RMS ripple current rating is higher than 50% of the output current. The input capacitor should be placed close to the IN and GND pins of the IC, with the shortest traces possible. In the case of tantalum or electrolytic types, a ceramic capacitor is Innovative PowerTM -7- www.active-semi.com Copyright © 2015-2017 Active-Semi, Inc. ACT4528 Rev 2, 06-Jan-2016 APPLICATIONS INFORMATION Current Sense Resistor The traces leading to and from the sense resistor can be significant error sources. With small value sense resistors, trace resistance shared with the load can cause significant errors. It is recommended to connect the sense resistor pads directly to the CSP and CSN pins using “Kelvin” or “4-wire” connection techniques as shown below. PCB Load Trace Kevin Sense Traces Sense Resistor Current Limit Setting If output current hits current limit, output voltage drops to keep the current to a constant value. The following equation calculates the constant current limit. ILimit ( A ) 66 mV Rcs ( m ) (6) Where Rcs is current sense resistor. Innovative PowerTM -8- www.active-semi.com Copyright © 2015-2017 Active-Semi, Inc. ACT4528 Rev 2, 06-Jan-2016 APPLICATIONS INFORMATION 4) Schottky anode pad and IC exposed pad should be placed close to ground clips in CLA applications PCB Layout Guidance When laying out the printed circuit board, the following checklist should be used to ensure proper operation of the IC. 5) Use “Kelvin” or “4-wire” connection techniques from the sense resistor pads directly to the CSP and CSN pins. The CSP and CSN traces should be in parallel to avoid interference. 1) Arrange the power components to reduce the AC loop size consisting of CIN, VIN pin, SW pin and the Schottky diode. 6) Place multiple vias between top and bottom GND planes for best heat dissipation and noise immunity. 2) The high power loss components, e.g. the controller, Schottky diode, and the inductor should be placed carefully to make the thermal spread evenly on the board. 7) Use short traces connecting HSB-CHSB-SW loop. 3) Place input decoupling ceramic capacitor CIN as close to VIN pin as possible. CIN should be connected to power GND with several vias or short and wide copper trace. 8) SW pad is noise node switching from VIN to GND. It should be isolated away from the rest of circuit for good EMI and low noise operation. Example PCB Layout Innovative PowerTM -9- www.active-semi.com Copyright © 2015-2017 Active-Semi, Inc. ACT4528 Rev 2, 06-Jan-2016 Typical Application Circuit CSN 4.5V to 40V IN C1 47ìF C2 10ìF GND C3 22nF HSB U1 ACT4528 DP Rcs 25mÙ SW 5V/9V/12V L1 47ìH CSP Vout DM D1 SK54L C4 C5 22ìF 220ìF C6 2.2ìF DD+ GND BOM List for 2.4A Car Charger ITEM REFERENCE DESCRIPTION MANUFACTURER QTY 1 U1 IC, ACT4528 SOP-8EP Active-Semi 1 2 C1 Capacitor, Electrolytic, 47µF/35V Murata, TDK 1 3 C2 Capacitor, Ceramic, 10µF/25V, 1206, SMD Murata, TDK 1 4 C3 Capacitor, Ceramic, 22nF/25V, 0603, SMD Murata, TDK 1 5 C4 Capacitor, Ceramic, 22µF/16V, 1206, SMD Murata, TDK 1 6 C5 Capacitor, Electrolytic, 220µF/16V Murata, TDK 1 7 C6 Capacitor, Ceramic, 2.2µF/16V, 0805, SMD Murata, TDK 1 8 L1 Inductor, 47µH, 3.5A, 20% 9 D1 Diode, Schottky, 40V/5A, SK54L Panjit 1 10 Rcs Chip Resistor, 25mΩ, 1206, 1/2W, 1% SART 1 Innovative PowerTM 1 - 10 - www.active-semi.com Copyright © 2015-2017 Active-Semi, Inc. ACT4528 Rev 2, 06-Jan-2016 TYPICAL PERFORMANCE CHARACTERISTICS (Schematic as show in typical application circuit, Ta = 25°C, unless otherwise specified) Efficiency vs. Load current ( 9V Vout) Efficiency vs. Load current ( 5V Vout) 90 Efficiency (%) Efficiency (%) 90 95 85 VIN =24V 80 75 85 80 75 70 70 65 65 60 60 0 500 1500 1000 2000 0 2500 500 2000 2500 Output CC/CV Curve (5V Vout) Efficiency vs. Load current ( 12V Vout) VIN =12V VIN =24V 5.0 Output Voltage (V) 90 ACT4528-003 95 ACT4528-004 6.0 100 Efficiency (%) 1500 1000 Load Current (mA) Load Current (mA) 85 80 75 70 VIN =24V 4.0 VIN =12V 3.0 2.0 1.0 65 60 0 0 500 1500 1000 2000 0 2500 500 Output CC/CV Curve (9V Vout) 2000 2500 3000 ACT4528-006 14.0 ACT4528-005 12.0 Output Voltage (V) 8.0 6.0 4.0 VIN =24V 1500 Output CC/CV Curve (12V Vout) 10.0 2.0 1000 Output Current (mA) Load Current (mA) Output Voltage (V) VIN =12V VIN =24V ACT4528-002 VIN =12V 95 100 ACT4528-001 100 VIN =12V 10.0 8.0 6.0 4.0 2.0 VIN =12V VIN =24V 0 0 0 500 1000 1500 2000 2500 3000 0 Output Current (mA) Innovative PowerTM 500 1000 1500 2000 2500 3000 Output Current (mA) - 11 - www.active-semi.com Copyright © 2015-2017 Active-Semi, Inc. ACT4528 Rev 2, 06-Jan-2016 TYPICAL PERFORMANCE CHARACTERISTICS (Schematic as show in typical application circuit, Ta = 25°C, unless otherwise specified) Output Over Voltage (5V Vout) Start up into CC Mode ACT4528-008 ACT4528-007 CH1 CH1 VOUT = 5.1V RLORD = 1.5Ù IOUT = 2.65A VIN = 12V CH2 CH2 CH3 CH1: VIN, 10V/div CH2: VOUT, 2V/div CH3: IOUT, 2A/div TIME: 400µs/div CH1: VOUT, 1V/div CH2: SW, 10V/div TIME: 1ms/div Load Transient (80mA-1A-80mA) Vin=12V, Vout=5V Load Transient (1A-2.4A-1A) Vin=12V, Vout=5V ACT4528-010 ACT4528-009 CH1 CH1 CH2 CH2 CH1: VOUT, 100mV/div CH2: IOUT, 1A/div TIME: 400us//div CH1: VOUT, 200mV/div CH2: IOUT, 1A/div TIME: 400us//div Load Transient (80mA-1A-80mA) Vin=12.6V, Vout=12V Load Transient (1A-2.4A-1A) Vin=12.6V, Vout=12V ACT4528-012 ACT4528-011 CH1 CH1 CH2 CH2 CH1: VOUT, 200mV/div CH2: IOUT, 1A/div TIME: 400us//div Innovative PowerTM CH1: VOUT, 200mV/div CH2: IOUT, 1A/div TIME: 400us//div - 12 - www.active-semi.com Copyright © 2015-2017 Active-Semi, Inc. ACT4528 Rev 2, 06-Jan-2016 TYPICAL PERFORMANCE CHARACTERISTICS (Schematic as show in typical application circuit, Ta = 25°C, unless otherwise specified) Voltage Transient (5V-9V) Voltage Transient (9V-5V) ACT4528-014 ACT4528-013 CH1 CH1 CH1: VOUT, 2V/div TIME: 10ms//div CH1: VOUT, 2V/div TIME: 10ms//div Voltage Transient (5V-12V) Voltage Transient (12V-5V) ACT4528-016 ACT4528-015 CH1 CH1 CH1: VOUT, 2V/div TIME: 10ms//div Innovative PowerTM CH1: VOUT, 2V/div TIME: 10ms//div - 13 - www.active-semi.com Copyright © 2015-2017 Active-Semi, Inc. ACT4528 Rev 2, 06-Jan-2016 PACKAGE OUTLINE SOP-8EP PACKAGE OUTLINE AND DIMENSIONS SYMBOL DIMENSION IN MILLIMETERS DIMENSION IN INCHES MIN MAX MIN MAX A 1.350 1.727 0.053 0.068 A1 0.000 0.152 0.000 0.006 A2 1.245 1.550 0.049 0.061 b 0.330 0.510 0.013 0.020 c 0.170 0.250 0.007 0.010 D 4.700 5.100 0.185 0.200 D1 3.202 3.402 0.126 0.134 E 3.734 4.000 0.147 0.157 E1 5.800 6.200 0.228 0.244 E2 2.313 2.513 0.091 0.099 e 1.270 TYP 0.050 TYP L 0.400 1.270 0.016 0.050 è 0° 8° 0° 8° Active-Semi, Inc. reserves the right to modify the circuitry or specifications without notice. Users should evaluate each product to make sure that it is suitable for their applications. Active-Semi products are not intended or authorized for use as critical components in life-support devices or systems. Active-Semi, Inc. does not assume any liability arising out of the use of any product or circuit described in this datasheet, nor does it convey any patent license. Active-Semi and its logo are trademarks of Active-Semi, Inc. For more information on this and other products, contact [email protected] or visit http://www.active-semi.com. is a registered trademark of Active-Semi. Innovative PowerTM - 14 - www.active-semi.com Copyright © 2015-2017 Active-Semi, Inc.