GS1662 High Efficiency, Step-up DC/DC Converter Features Description The GS1662 is a compact, high efficiency, and Output Voltage up to 24V Internal MOSFET with high switch current up to 3A 20µA Quiescent (Switch-off) Supply Current 90% Efficiency Up to 450KHz Switching Frequency an error amplifier, ramp generator, comparator, switch pass element and driver in which providing a stable and high efficient operation over a wide range of load currents. It operates in stable waveforms without external compensation. Using Internal Power Switches SOP-8L Package The low start-up input voltage below 1.6V. The high switching rate minimized the size of external Applications low voltage step-up DC/DC converter including PDA DSC LCD Panel components. Besides, the 20µA low quiescent (Switch-off) current together with high efficiency maintains long battery lifetime. The output voltage is set with two external resistors. RF-Tags MP3 Wireless Equipment Portable Instrument 1 TEL:0755-27668758/29469758 web:http://www.zgsemi.com www.086ic.cn GS1662 Typical Application Circuits GS1662 Figure 1 （2.6V Stat-up input Voltage) ＊RX can be a Zener Diodes or Resistor: The Ratio of RX/RVDD must to keep VDD voltage less than 5.5V. The resistor RM can be set to 50mΩ usually. GS1662 Figure 2 （1.1V Stat-up input Voltage） ＊ The resistor RM can be set to 50mΩ usually. TEL:0755-27668758/29469758 web:http://www.zgsemi.com www.086ic.cn 2 GS1662 Absolute Maximum Ratings (Note 1) Supply Voltage…………………………………………………………………….…−0.3V to 6V SW Pin Switch Voltage……………………………………………………………………−0.3V to 28V Other I/O Pin Voltages……………………………………………………………−0.3V to 6V SW Pin Switch Current ……………………………………………………………...………………..3A Operating Junction Temperature…………………………………………………….……………..125°C Storage Temperature Range ……………………………………………….−65°C ~ +150°C Note 1: Absolute Maximum ratings are threshold limit values that must not be exceeded even for an instant under any conditions. Moreover, such values for any two items must not be reached simultaneously. Operation above these absolute maximum ratings may cause degradation or permanent damage to the device. These are stress ratings only and do not necessarily imply functional operation below these limits. Pin Assignment 8 7 6 5 SW 1 2 3 4 PIN NUMBER PIN NAME FUNCTION 1 SW Switch Output 2 SW Switch Output 3 SOE Source of the MOSFET 4 SOE Source of the MOSFET 5 GND Ground 6 VDD Input 7 EN ON/OFF Control(High Enable) 8 FB Feedback SOP- 8L TEL:0755-27668758/29469758 web:http://www.zgsemi.com www.086ic.cn 3 GS1662 Electrical Characteristics (VIN = 1.5V, VDD set to 3.3V, Load Current = 0A, TA = 25°C, unless otherwise specified) Parameter Test Conditions Min Typ Max Units Start-UP Voltage IL = 1mA Operating VDD Range VDD pin voltage Switch-off Current I (VIN) VIN = 5V 20 No Load Current I (VIN) VIN = 1.5V, VOUT = 3.3V 40 Feedback Reference Voltage Close Loop, VDD = 3.3V Switching Frequency VDD = 3.3V SW ON Resistance VDD = 3.3V 0.07 Ω Current Limit Setting VDD = 3.3V 3 A Line Regulation VIN = 1.5 ~ 2.5V, IL = 100mA 55 mV/V Load Regulation VIN = 2.5V, IL = 1 ~ 300mA 0.1 mV/mA En Input High 1.00 V 2 1.182 5.5 1.212 TEL:0755-27668758/29469758 µA µA 1.242 V 450 KHz 1 V En Input Low Maximum VRM V 0.6 145 web:http://www.zgsemi.com V mV www.086ic.cn 4 GS1662 Typical Performance Characteristics ℃ TA=25 , CIN =10 µF, COUT =20 µF, L=4.7 µH, unless otherwise noted. Refer to Test Circuit Figure 1 Efficiency vs. Output Current (Vout=5V) Output Voltage vs. Load Current (Vout=5V) 100 6 VIN =2V 90 5.5 70 Output Voltage (V) Efficiency(%) 80 VIN=1.5V 60 VIN =1V 50 40 30 20 VIN=1.5V 5 V IN =1V 4.5 VIN =2V 4 3.5 10 3 0 10 100 Output Current (mA) 0 1000 Efficiency vs. Output Current (Vout=5V) 5.5 VIN=3V Output Voltage (V) 70 VIN =3.6V 60 600 700 6 V IN =4.2V 80 Efficiency(%) 200 300 400 500 Load Current (mA) Output Voltage vs. Load Current (Vout=5V) 100 90 100 50 40 30 20 VIN =4.2V 5 4.5 VIN =3V V IN =3.6V 4 3.5 10 3 0 10 100 1000 Output Current (mA) TEL:0755-27668758/29469758 10000 0 300 600 900 1200 1500 1800 Load Current (mA) web:http://www.zgsemi.com www.086ic.cn 5 GS1662 Output Voltage vs. Load Current (Vout=3.3V) Efficiency vs. Output Current (Vout=3.3V) 4 100 V IN =2V 90 3.5 70 Output Voltage (V) Efficiency(%) 80 V IN=1V 60 50 40 30 3 1.5 1 10 0.5 0 0 100 1000 Output Current (mA) 10000 0 300 600 900 1200 Load Current (mA) Output Voltage vs. Load Current (Vout=3.3V) Efficiency vs. Output Current (Vout=3.3V) 4 100 90 3.5 70 Output Voltage (V) V IN =3V 80 Efficiency(%) VIN =2V 2 20 10 VIN =1V 2.5 VIN =2.5V 60 50 40 30 20 3 VIN =2.5V 2.5 VIN =3V 2 1.5 1 0.5 10 0 0 10 100 1000 Output Current (mA) TEL:0755-27668758/29469758 10000 0 300 600 900 1200 1500 1800 2100 Load Current (mA) web:http://www.zgsemi.com www.086ic.cn 6 GS1662 ℃ TA=25 , CIN =10 µF, COUT =20 µF, L=10 µH (high saturated inductor current), unless otherwise noted. Output Voltage vs. Load Current (Vout=12V) Efficiency vs. Output Current (Vout=12V) 12 100 11.8 VIN =4.2V 90 70 Output Voltage (V) Efficiency(%) 80 VIN=3.6V VIN =2.5V 60 50 40 30 VIN =4.2V 11.6 VIN=2.5V 11.4 11.2 VIN =3.6V 11 10.8 10.6 10.4 20 10.2 10 10 0 0 10 100 Output Current (mA) 100 1000 300 400 500 Load Current (mA) Output Voltage vs. Load Current (Vout=12V) Efficiency vs. Output Current (Vout=12V) 12 100 VIN =7.2V 90 VIN=5V 70 V IN =6V 60 11.8 Output Voltage (V) 80 Efficiency(%) 200 50 40 30 VIN =7.2V 11.6 11.4 VIN=5V 11.2 11 VIN =6V 10.8 10.6 10.4 20 10.2 10 10 0 0 10 100 1000 Output Current (mA) TEL:0755-27668758/29469758 10000 300 600 900 1200 Load Current (mA) web:http://www.zgsemi.com www.086ic.cn 7 1500 GS1662 Pin Information SW (Pin 1/ Pin 2): Switch Pin. Connect inductor between SW and VIN. Keep these PCB trace lengths as short and wide as possible to reduce EMI and voltage overshoot. SOE (Pin 3/ Pin 4): Source of the MOSFET. Connect resistor to GND. GND (Pin 5): Signal and Power Ground. Provide a short direct PCB path between GND and the (–) side of the output capacitor(s). VDD (Pin 6): Input positive power pin. EN (Pin 7): En Control Input. Forcing this pin above 1V enables the part. Forcing this pin below 0.6V shuts down the device. In shutdown, all functions are disabled, drawing <1µA supply current. Do not leave EN floating. FB (Pin 8): Feedback Input to the gm Error Amplifier. Connect resistor divider tap to this pin. The output voltage can be adjusted from 3.3V to 20V by: VOUT = 1.212V • [1 + (R1/R2)]. Block Diagram TEL:0755-27668758/29469758 web:http://www.zgsemi.com www.086ic.cn 8 GS1662 Application Information Output Voltage Setting Referring to Typical Application Circuits, the output voltage of the switching regulator (VOUT) can be set with Equation (1). Current-limiting Resistance Setting Feedback Loop Design Referring to the Typical Application Circuits. The selection of R1 and R2 based on the trade-off between quiescent current consumption and interference immunity is stated below: Follow Equation (1) Higher R reduces the quiescent current (Path current = 1.212V/R2), however resistors beyond 5MW are not Recommended. Lower R gives better noise immunity, and is less sensitive to interference, layout parasitics, FB node leakage, and improper probing to FB pin. For applications without standby or suspend modes, lower values of R1 and R2 are preferred. For applications concerning the current consumption in standby or suspend modes, the higher values of R1 and R2 are needed. Such high impedance feedback loop is sensitive to any interference, which requires careful PCB layout and avoid any interference, especially to FB pin. To improve the system stability, a proper value capacitor between FB pin and GND pin is suggested. An empirical suggestion is around 22pF. PCB Layout Guide PCB Layout shall follow these guidelines for better system stability: A full GND plane without gap break. VDD to GND noise bypass - Short and wide connection for the 20uF MLCC capacitor between Pin 6 and Pin 5. VIN to GND noise bypass - Add a 10uF capacitor close to L1 inductor, when VIN is not an idea voltage source. Minimized FB node copper area and keep far away from noise sources. TEL:0755-27668758/29469758 web:http://www.zgsemi.com www.086ic.cn 9 GS1662 Packaging Information SOP-8L Package Outline Dimension Symbol Dimensions In Millimeters Dimensions In Inches Min Max Min Max A 1.350 1.750 0.053 0.069 A1 0.100 0.250 0.004 0.010 A2 1.350 1.550 0.053 0.061 b 0.330 0.510 0.013 0.020 c 0.170 0.250 0.006 0.010 D 4.700 5.100 0.185 0.200 E 3.800 4.000 0.150 0.157 E1 5.800 6.200 0.228 0.244 e L θ 1.270(BSC) 0.050(BSC) 0.400 1.270 0° 8° TEL:0755-27668758/29469758 0.016 0° web:http://www.zgsemi.com 0.050 8° www.086ic.cn 10