PAM2400 3-Pin Synchronous Step-Up DC/DC Converter Features General Description n Schottky Diode Embedded, Saving Cost and Space n Low Start-up Voltage (0.9V) n High Efficiency up to 88% n Low Quiescent Current n Low Ripple and Noise n Available Output Voltage: 2.0V,2.7V,2.8V, 3.0V, 3.3V,3.8V and 5.0V n Space Saving Packages: SOT-89, SOT-23 n Pb-Free Package The PAM2400 is a high efficiency step-up DC/DC converter, delivering a fixed output voltage of 2.0V, 2.7V, 2.8V, 3.0V, 3.3V, 3.8V or 5.0V. The device starts up with an input voltage as low as 0.9V at 1mA load. The Pulse Frequency Modulation (PFM) scheme provides optimized performance for applications with light load and low input voltages. The PAM2400 employs a built-in synchronous rectifier, instead of requiring an external Schottky diode, so that to improve system efficiency and save system cost and PCB area. Applications n n n n n n Pagers Cameras Wireless Microphones Pocket Organizers Battery Backup Suppliers Portable Instruments The internal PFM control circuit operates at constant switching frequency of 100KHz. Only three external components are required. The space saving SOT-89 and SOT-23 packages make t h e PA M 2 4 0 0 i d e a l f o r s p a c e c o n s c i o u s applications. Block Diagram Typical Application V IN VO L1 100 μ H SW PAM2400 SW VOUT VOUT 1M GND + C IN 22 μ F + + 1.25V REF CO 47 μ F Enable GND OSC 100KHz Power Analog Microelectronics , Inc www.poweranalog.com 12/2007 Rev 1.0 1 PAM2400 3-Pin Synchronous Step-Up DC/DC Converter Pin Configuration & Marking Information SOT89-3 V: Voltage Code X: Internal Code Y: Year W: Week P2400V XXXYW 1 2 3 SOT23-3 3 CC: Product Code of PAM2400 V: Voltage Code Y: Year W: Week CCVYW 1 2 Pin Number Name Function 1 GND Ground 2 VOUT Output 3 SW Switch Pin Absolute Maximum Ratings These are stress ratings only and functional operation is not implied . Exposure to absolute maximum ratings for prolonged time periods may affect device reliability . All voltages are with respect to ground . Operating Temperature Range.........-40 ° C to 85 ° C Storage Temperature Range...........-65 ° C to 150 ° C Lead Temperature (Soldering 5 Sec.)...........300 ° C Supply Voltage............................................ 6.0V SW pin Voltage............................................. 6.0V SW pin Switch Current..................................0.4A Thermal Information Parameter Symbol Thermal Resistance (Junction to Case) θJC Thermal Resistance (Junction to Ambient) θJA Internal Power Dissipation PD Package Maximum SOT89-3 45 SOT-23 130 SOT89-3 160 SOT-23 250 SOT89-3 550 SOT-23 400 Unit °C/W °C/W mW Power Analog Microelectronics , Inc www.poweranalog.com 12/2007 Rev 1.0 2 PAM2400 3-Pin Synchronous Step-Up DC/DC Converter Electrical Characteristic C IN=22 μ F,C O=47 μ F,T A=25°C, unless otherwise noted. Parameter Symbol Output Voltage Accuracy Input Voltage Test Conditions VIN =1.5V, IO=1mA MIN TYP -3 VIN MAX UNIX +3 % 5.5 V Start-Up Voltage VSTA RT IO=1mA 0.9 1.0 V Hold-on Voltage VHOLD IO=0mA,V IN =2V to 0V 0.4 0.6 V Supply Current IDD1 VO =VO X 1.05 8.5 12 μA (Vo pin) IDD2 VO =VO X 0.95 33 No-Load Input Current IIN SW Leakage Current IO=0mA， VIN =1.5V Vo=2.0V 19 Vo=2.7V 23 Vo=2.8V 25 Vo=3.0V 26 Vo=3.3V 29 Vo=3.8V 34 Vo=5.0V 45 VSW =5V,V IN =V O+0.5V μA μA 1.0 SW Switch-On Resistance R ON Isw=50mA Oscillator Duty Cycle DC VIN =VO * 90% 70 80 90 % Oscillator Frequency fOS C Current Limit Appears 70 100 130 kHz Efficiency (Note 2) η 1.0 μA Peak value 85 Ω % Note 1: V O means the nominal output voltage Note 2: Refer to “Efficiency vs Output Current” curve Power Analog Microelectronics , Inc www.poweranalog.com 12/2007 Rev 1.0 3 PAM2400 3-Pin Synchronous Step-Up DC/DC Converter Typical Performance Characteristics 2.4 2.1 2.2 2.06 Output voltage(V) Output voltage(V) C IN=22 μ F,C O=47 μ F,T A=25°C, unless otherwise noted. Vo=2.0V 1.Output voltage vs Output current 2 1.8 Vin=0.9V 1.6 4. Output Voltage vs Temperature 2.02 1.98 1.94 Vin=1.2V Vin=1.5V 1.9 1.4 0 30 60 90 120 0 150 30 90 120 150 120 150 Temperature(℃) Output current(mA) 2.Efficiency vs Output Current 90 60 5. I DD1 vs Temperature 14 80 12 10 60 IDD1(uA) Efficiency(%) 70 50 40 30 6 4 20 Vin=0.9V 10 Vin=1.2V 2 Vin=1.5V 0 0 0 20 40 60 80 100 0 120 30 60 90 Temperature(℃) Output current(mA) 1.2 8 3.Start up Voltage and Hold on voltage vs Output Current Input voltage(V) 1 0.8 0.6 0.4 0.2 Start up Hold on 0 0 5 10 15 Output current(mA) 20 25 Power Analog Microelectronics , Inc www.poweranalog.com 12/2007 Rev 1.0 4 PAM2400 3-Pin Synchronous Step-Up DC/DC Converter Typical Performance Characteristics (continued) C IN=22 μ F,C O=47 μ F,T A=25°C, unless otherwise noted. Vo=2.7V 1.Output voltage vs Output current 3 Output voltage(V) Output voltage(V) 2.5 2 1.5 1 Vin=0.9V 0.5 4. Output Voltage vs Temperature 2.8 Vin=1.2V 2.76 2.72 2.68 2.64 Vin=1.5V 0 2.6 0 30 60 90 120 0 30 Output current(mA) 120 150 120 150 5. I DD1 vs Temperature 16 80% 14 70% 12 60% IDD1(uA) Efficiency 90 Temperature(℃) 2.Efficiency vs Output Current 90% 60 50% 40% 30% 20% 8 6 4 Vin=0.9V Vin=1.2V 10% 10 2 Vin=1.5V 0 0% 0 20 40 60 80 100 120 0 30 60 90 Temperature(℃) Output current(mA) 3.Start up Voltage and Hold on voltage vs Output Current 1.2 1 Vin(V) 0.8 0.6 0.4 0.2 Start up Hold on 0 0 5 10 15 Output current(mA) 20 25 Power Analog Microelectronics , Inc www.poweranalog.com 12/2007 Rev 1.0 5 PAM2400 3-Pin Synchronous Step-Up DC/DC Converter Typical Performance Characteristics (continued) C IN=22 μ F,C O=47 μ F,T A=25°C, unless otherwise noted. Vo=2.8V 1.Output voltage vs Output current 3 Output voltage(V) Output voltage(V) 2.5 2 1.5 1 Vin=0.9V 0.5 4. Output Voltage vs Temperature 2.9 2.86 2.82 2.78 2.74 Vin=1.2V Vin=1.5V 0 2.7 0 30 60 90 120 0 30 Output current(mA) 90 120 150 120 150 Temperature(℃） 2.Efficiency vs Output Current 90% 16 80% 14 70% 12 IDD1(uA) 60% Efficiency 60 50% 40% 30% 20% Vin=0.9V 10% Vin=1.2V 5. I DD1 vs Temperature 10 8 6 4 2 Vin=1.5V 0 0% 0 30 60 90 0 120 30 60 90 Temperature(℃) Output current(mA) 3.Start up Voltage and Hold on voltage vs Output Current 1.4 Input voltage(V) 1.2 1 0.8 0.6 0.4 0.2 Start up Hold on 0 0 5 10 15 20 25 Output current(mA) Power Analog Microelectronics , Inc www.poweranalog.com 12/2007 Rev 1.0 6 PAM2400 3-Pin Synchronous Step-Up DC/DC Converter Typical Performance Characteristics (continued) C IN=22 μ F,C O=47 μ F,T A=25°C, unless otherwise noted. Vo=3.0V 3.2 1.Output voltage vs Output current Output Voltage(V) Output voltage(V) 3 2.8 2.6 2.4 Vin=0.9V 2.2 4. Output Voltage vs Temperature 3.1 3.06 3.02 2.98 2.94 Vin=1.2V Vin=1.5V 2.9 2 0 30 60 90 120 0 30 Output current(mA) 120 150 120 150 5. I DD1 vs Temperature 16 90 14 80 12 70 IDD1(uA) Efficiency(%) 90 Temperature(℃) 2.Efficiency vs Output Current 100 60 60 50 40 10 8 6 30 20 Vin=0.9V 10 Vin=1.2V 4 2 Vin=1.5V 0 0 0 30 60 90 120 0 Output current(mA) 30 60 90 Temperature(℃) 3.Start up Voltage and Hold on voltage vs Output Current 1.2 Input voltage(V) 1 0.8 0.6 0.4 0.2 Start up Hold on 0 0 5 10 15 20 25 Output current(mA) Power Analog Microelectronics , Inc www.poweranalog.com 12/2007 Rev 1.0 7 PAM2400 3-Pin Synchronous Step-Up DC/DC Converter Typical Performance Characteristics (continued) C IN=22 μ F,C O=47 μ F,T A=25°C, unless otherwise noted. Vo=3.3V 1.Output voltage vs Output current 4 4. Output Voltage vs Temperature 3.4 3.36 3 Output Voltage(V) Output voltage(V) 3.5 2.5 2 1.5 Vin=0.9V 1 Vin=1.2V 0.5 Vin=1.8V 3.32 3.28 3.24 Vin=1.5V Vin=2.0V 0 3.2 0 30 60 90 120 Output current(mA) 0 150 2.Efficiency vs Output Current 16 85% 14 80% 12 IDD1(uA) 75% Efficiency 60 90 120 150 120 150 Temperature(℃) 90% 70% Vin=0.9V 65% 30 5. I DD1 vs Temperature 10 8 6 Vin=1.2V 60% 4 Vin=1.5V Vin=1.8V 55% 2 Vin=2V 50% 0 0 30 60 90 120 150 0 Output current(mA) 1.4 30 60 90 Temperature(℃) 3.Start up Voltage and Hold on voltage vs Output Current Input voltage(V) 1.2 1 0.8 0.6 0.4 0.2 Start up Hold on 0 0 5 10 15 20 25 Output current(mA) Power Analog Microelectronics , Inc www.poweranalog.com 12/2007 Rev 1.0 8 PAM2400 3-Pin Synchronous Step-Up DC/DC Converter Typical Performance Characteristics (continued) C IN=22 μ F,C O=47 μ F,T A=25°C, unless otherwise noted. Vo=3.8V 4 1.Output voltage vs Output current 4. Output Voltage vs Temperature 3.9 Output voltage(V) 3.5 3.86 Output voltage(V) 3 2.5 2 1.5 Vin=0.9V Vin=1.2V 1 Vin=1.5V 0.5 3.82 3.78 3.74 Vin=1.8V Vin=2V 0 3.7 0 30 60 90 Output current(mA) 0 120 60 90 120 150 120 150 Temperature(℃) 2.Efficiency vs Output Current 90% 5. I DD1 vs Temperature 18 16 80% 70% IDD1(uA) Efficiency 30 60% Vin=0.9V 50% Vin=1.2V Vin=1.5V 40% Vin=1.8 14 12 10 8 6 4 2 Vin=2V 0 30% 0 30 60 90 0 120 30 60 90 Temperature(℃) Output current(mA) 3.Start up Voltage and Hold on voltage vs Output Current 1.4 Input voltage(V) 1.2 1 0.8 0.6 0.4 0.2 Start up Hold on 0 0 5 10 15 20 25 Output current(mA) Power Analog Microelectronics , Inc www.poweranalog.com 12/2007 Rev 1.0 9 PAM2400 3-Pin Synchronous Step-Up DC/DC Converter Typical Performance Characteristics (continued) C IN=22 μ F,C O=47 μ F,T A=25°C, unless otherwise noted. Vo=5.0V 1.Output voltage vs Output current 6 Output Voltage(V) Output voltage(V) 5 4 3 Vin=0.9V 2 Vin=1.2V Vin=1.5V 1 4. Output Voltage vs Temperature 5.1 5.06 5.02 4.98 4.94 Vin=1.8V Vin=2V 0 0 30 60 90 4.9 120 0 30 Output current(mA) 60 90 120 150 120 150 Temperature(℃) 2.Efficiency vs Output Current 5. I DD1 vs Temperature 25 95% 90% 20 80% IDD1(uA) Efficiency 85% 75% 70% 15 10 Vin=0.9V 65% Vin=1.2V 60% 5 Vin=1.5V 55% Vin=1.8V Vin=2V 50% 0 20 0 40 60 80 100 0 120 30 60 90 Temperature(℃) Output current(mA) 3.Start up Voltage and Hold on voltage vs Output Current 1.4 Input voltage(V) 1.2 1 0.8 0.6 0.4 0.2 Start up Hold on 0 0 5 10 15 20 25 Output current(mA) Power Analog Microelectronics , Inc www.poweranalog.com 12/2007 Rev 1.0 10 PAM2400 3-Pin Synchronous Step-Up DC/DC Converter Application Information Inductor Selection V RIPPLE=V RIPPLE(C)+V RIPPLE(ESR) V RIPPLE(C) ≈1 / 2 *( L /( C ( OUT) *(( V OUT( MAX) - V IN( MIN) ) ) ) ) *( I 2PEAK- I 2OUT) To select an inductor for PAM2400 applications, it should be noted that the inductors current saturation rating should be larger than the possible peak inductor current to ensure proper operation, and it should have low DCR (DC resistance). Using an inductor with the saturation current lower than the possible peak indicator current can cause a dramatic drop in the inductance and severely decay the maximum output current levels. An inductor is chosen based on desired ripple current. Larger inductors result in lower ripple currents, and smaller ones higher ripple. A 100uH inductor will b e a s u i t a b l e c h o i c e f o r m o s t PA M 2 4 0 0 applications. The following equation can also help to get a good approximate value for the inductor. And V RIPPLE( ESR) = I PEAK* R ESR( COUT) Where Ipeak is the peak inductor current . Multilayer ceramic capacitors are a good choice as they have extremely low ESR and are available in small footprints. Capacitance and ESR variation vs temperature should be considered for best performance in applications with wide operating temperature ranges. Component Power Dissipation Operating in discontinuous mode, power loss in the winding resistance of the inductor is approximately equal to L=V IN*D /(△I L* f ) D ( Duty Cycle) = 1 - V IN/ V OUT PDL=2/3(T ON/L)*R D*((V OUT+V F)/V OUT)*P OUT The power dissipated in a switch loss is ΔI L (Ripple Current) in the Inductor, i.e., 20% to 40% of the maximum inductor current(Ip). PDsw=2/3(T ON/L)*R ON*((V OUT+V D-V IN)/V OUT)*(P OUT) F (Switching Frequency)=100K. The power disspated in rectifier diode(Internal Diode) is Output and Input Capacitor Selection PDd=V D*I OUT Input Capacitor Where POUT=VOUT*IOUT, RD=Inductor DCR, V D=Diode drop An input capacitor of minimum 22μF is recommended to reduce input ripple and switching noise for normal operating conditions. A larger capacitor with lower ESR (Equivalent Series Resistance) may be needed if the application requires very low input ripple. Usually ceramic capacitors are a good choice for applications. Note that the input capacitor should be located as close as possible to the IC. PC Board Layout considerations Careful PC board layout is important for minimizing ground bounce and noise. Keep the IC's GND pin and the ground leads of input and output capacitors as close as possible. In addition, connect L1 and SW with short and wide connections. Output Capacitor A minimum 47μF output capacitor is recommended and may-be a larger one is better. The total output voltage ripple has two components, the capacitive ripple caused by the charging and discharging on the output capacitor, and the ohmic ripple due to the capacitor's equivalent series resistance (ESR): Power Analog Microelectronics , Inc www.poweranalog.com 12/2007 Rev 1.0 11 PAM2400 3-Pin Synchronous Step-Up DC/DC Converter Ordering Information PAM2400 X X X XXX Output Voltage Number of Pins Package Type Pin Configuration Pin Configuration A Type 1. GND Package Type Number of Pins A: SOT-23-3 A: 3 C: SOT-89-3 Output Voltage 200: 2.0V 270: 2.7V 2. VOUT 280: 2.8V 3. SW 300: 3.0V 330: 3.3V 380: 3.8V 500: 5.0V Part Number Output Voltage Marking Package Type MOQ PAM2400AAA200 2.0V CCGYW SOT-23-3 3,000Unites/Tape&Reel PAM2400ACA200 2.0V SOT-89-3 1,000Unites/Tape&Reel PAM2400AAA270 2.7V SOT-23-3 3,000Unites/Tape&Reel PAM2400ACA270 2.7V SOT-89-3 1,000Unites/Tape&Reel PAM2400AAA280 2.8V SOT-23-3 3,000Unites/Tape&Reel PAM2400ACA280 2.8V SOT-89-3 1,000Unites/Tape&Reel PAM2400AAA300 3.0V SOT-23-3 3,000Unites/Tape&Reel PAM2400ACA300 3.0V SOT-89-3 1,000Unites/Tape&Reel PAM2400AAA330 3.3V SOT-23-3 3,000Unites/Tape&Reel PAM2400ACA330 3.3V SOT-89-3 1,000Unites/Tape&Reel PAM2400AAA380 3.8V SOT-23-3 3,000Unites/Tape&Reel PAM2400ACA380 3.8V SOT-89-3 1,000Unites/Tape&Reel PAM2400AAA500 5.0V SOT-23-3 3,000Unites/Tape&Reel PAM2400ACA500 5.0V SOT-89-3 1,000Unites/Tape&Reel P2400G XXXYW CCHYW P2400H XXXYW CCRYW P2400R XXXYW CCCYW P2400C XXXYW CCDYW P2400D XXXYW CCEYW P2400E XXXYW CCFYW P2400F XXXYW Power Analog Microelectronics , Inc www.poweranalog.com 12/2007 Rev 1.0 12 PAM2400 3-Pin Synchronous Step-Up DC/DC Converter Outline Dimension SOT89-3 4 . 5 0 . 05 1 . 650 REF 1 . 50 0 . 05 2 . 5 0 . 05 4 . 20 0 . 05 1 . 400 REF 6’ 1 . 00 0 . 07 1 . 50 1 . 50 3 . 00 0 . 025 0 . 46 0 . 025 0 . 38 0 . 01 6’-2X 6’-2X ( Unit : mm ) Power Analog Microelectronics , Inc www.poweranalog.com 12/2007 Rev 1.0 13 PAM2400 3-Pin Synchronous Step-Up DC/DC Converter Outline Dimension SOT23-3 D B A A1 E H Dim S e Millimeters Min. Typ. Max. A 1.00 1.15 1.30 A1 0.00 0.05 0.10 B 0.35 0.43 0.51 C 0.10 0.175 0.25 D 2.70 2.90 3.10 E 1.40 1.60 1.80 e L C 1.90BSC H 2.40 L 0.37 2.70 3.00 Power Analog Microelectronics , Inc www.poweranalog.com 12/2007 Rev 1.0 14