DN06042/D Design Note – DN06042/D Self Protecting Cigarette Lighter Adapter (CLA) Device Application Input Voltage Output Power Topology I/O Isolation NCP3063 Consumer/Industrial 8-24 V 4W Buck None Characteristic Output Voltage Output Current Oscillator Frequency Output Voltage Ripple Calculated Inductor peak Current (390 uH) Calculated Duty Cycle Load Regulation Iout = 0.04-1A) Line regulation to 5V Iout = 1A) Iout = 0.25A) CLA Converter Dimensions in inches (mm) Min 4.98 0 Max 5.03 1 12 .83 24 Typ 5.01 0.8 53 32 .86 50 80 .89 78 Unit V A kHz mVpk-pk A % 2 13 27 mV/A -1.5 .2 1.4 % 0.7 1.8 2.66 .686(17.4) x 2.754 (70) Circuit Description The NCP3063 is a hysteretic regulator with pulse by pulse current limiting and frequency adjustment. The NCP3063 CLA (Cigarette Lighter Adapter) design is configured in a buck topology and the frequency has been set to 53 kHz to reduce switching losses. The DFN package was selected as the exposed pad on the bottom spreads heat to the ground plane and grounding clip. The CLA has several built in safety features the first of which is a fuse F1 shown in layout in Figure 1 and schematically in Figure 3. The fuse serves as a second layer of short circuit protection incase the main switch is shorted. The fuse also serves as reverse polarity protection in the event that positive and negative voltages are reversed on the input. If the opposite polarity is applied at the input the diode D2 starts to conduct and the fuse F1 is blown protecting the end users device and the rest of the CLA. The designer can choose to implement a user replaceable fuse or a one time protection device depending on the user case. The first layer of short circuit protection is the pulse by pulse current limiting provided by the NCP3063 which can be set by the sense resistor R5. The user interface indicator R9 and D3 give real time visual feedback to the customer as to the functionality of the adapter. If a short circuit was to occur at the output or the fuse was to blown the LED D3 will cease to illuminate. Existing Product MC34063 SOIC-8 FET DPAK New Product NCP3063 DFN (4x4mm) New Thermally Enhanced Package Eliminates Need for External FET Rev 0 - April, 2008 DN06042/D Board Details Figure 1 – NCP3063 CLA Top Layout and Silkscreen Figure 2 – NCP3063 Bottom Layout and Silkscreen Rev 0 - April, 2008 DN06042/D Schematic Figure 3 – NCP3063 Schematic Rev 0 - April, 2008 DN06042/D Table 1 – NCP3063 CLA Bill of Materials Designator Quantity Description Value Tolerance Footprint Manufacturer Part Number Manufacturer D1-2 C2 CT CR1-2 C3 CO2 CIN1 D3 U1 R4 R7-8 R5 R9 R2 F1 R1 R3 R10 L1 2 1 1 2 1 1 1 1 1 3 1 1 1 1 1 2 1 40 V Schottky Ceramic Capacitor 6.3V Ceramic Capacitor 6.3V Ceramic Capacitor 35V Ceramic Capacitor 35V AE Capacitors 16V AE Capacitors 10V Green LED 1.5 A Switching Regulator Jumper TH Resistor SMT Resistor SMT Resistor Fast Acting Fuse SMT Resistor SMT Resistor Inductor 0.4 Ohm 0.60 Vf 1μF 6.8n NI 1 μF 1000 μF 330 μF 2mA 1.9V 40 V 1.5A Jumper 0.1 1.62k 2.55k 2A 7.68k NI 430 μH 59-10 603 603 603 1206 Through Hole Through Hole Through Hole SOIC-8 .4in th Through Hole 0603 0603 0603 0603 0603 Through Hole 1N5819RLG 06036D106MAT2A VJ0603Y682KXACW1BC NI 1206DD105KAT2A ESMG100ELL102ME11D ESMG350ELL331MJC5S LG 3369-EJ-1-0-2-BULK NCP3063BDR2G 923345-04-C 13FR100E CRCW06031K62JNEA CRCW06032K55FKEA 0467002.NR CRCW06037K68FKEA NA IN08014 ON Semiconductor AVX Corporation Vishay NI AVX Corporation United Chemi-Con United Chemi-Con Osram ON Semiconductor 3M Ohmite Vishay / Dale Vishay / Dale Littelfuse Inc Vishay / Dale NA ICE L1 1 Inductor 0.62 Ohm NA 20% 10% NI 10% 20% 20% NA NA NA 1% ±5.0% ±1.0% a^2s – 0.1105 ±1.0% NA 10% 10 % Through Hole RFB1010-391L Coilcraft 390 μH Rev 0 - April, 2008 DN06042/D Block Diagram – NCP3063 Figure 4 – NCP3063 Block Diagram Table 2 – NCP3063 Pin Description Rev 0 - April, 2008 DN06042/D Performance Information The following Figures show typical performance of the NCP3063 CLA evaluation board. 85% Efficiency (%) 80% 8V 75% 70% 65% 12V 60% 55% 50% 24 V 45% 40% 0.04 0.24 0.44 0.64 0.84 Iout (A) Figure 5– NCP3063 Efficiency 8V-24V with at 5V output Voltage. 5.03 5.025 8 5.02 Vout (v) 5.015 12 5.01 5.005 16 5 4.995 20 4.99 4.985 24 4.98 0.25 0.35 0.45 0.55 0.65 0.75 0.85 Iout (A) Figure 6 – NCP3063 Load Regulation Rev 0 - April, 2008 0.95 DN06042/D 3.0% 8 2.5% 2.0% 12 Error (%) 1.5% 1.0% 16 0.5% 0.0% 0.25 -0.5% 0.35 0.45 0.55 0.65 0.75 0.85 0.95 20 -1.0% 24 -1.5% -2.0% Iout (A) Figure 7 - NCP3063 Load Regulation Error 5.03 Output Voltage (V) 5.025 0.25 5.02 5.015 0.5 5.01 5.005 5 0.75 4.995 4.99 1 4.985 4.98 8 10 12 14 16 18 20 VIN (V) Figure 8 - NCP3063 Line Regulation Rev 0 - April, 2008 22 24 DN06042/D 3.0% 2.5% 0.25 2.0% Error (%) 1.5% 0.5 1.0% 0.5% 0.0% -0.5% 8 10 12 14 16 18 20 22 24 0.75 -1.0% 1 -1.5% -2.0% VIN (V) Figure 9 - NCP3063 Line Regulation Error Rev 0 - April, 2008 DN06042/D Figure 10- NCP3063 Output Ripple at 24 V to 5 V at a 1 A Load Figure 11- NCP3063 Output Ripple at 24 V to 5 V at a no load Rev 0 - April, 2008 DN06042/D Figure 12- NCP3063 Output Ripple at 8 V to 5 V at a 1 A Load Figure 13- NCP3063 Output Ripple at 8 V to 5 V at a no load Rev 0 - April, 2008 DN06042/D © 2008 ON Semiconductor. Disclaimer: ON Semiconductor is providing this design note “AS IS” and does not assume any liability arising from its use; nor does ON Semiconductor convey any license to its or any third party’s intellectual property rights. This document is provided only to assist customers in evaluation of the referenced circuit implementation and the recipient assumes all liability and risk associated with its use, including, but not limited to, compliance with all regulatory standards. ON Semiconductor may change any of its products at any time, without notice. Design note created by Bryan McCoy and Tim Kaske, e-mail: [email protected]; [email protected] Rev 0 - April, 2008