降压芯片 LP32031.5MHZ,600mA,High Efficiency Synchronous PWM Step-Down DC/DC ConvertGeneral DescriptionThe LP3203 is a constant frequency, current mode, PWM step-down converter. The device integrates a main switch and a synchronous rectifier for high efficiency. The 2.1V to 5.5V input voltage range makes the LP3203 is ideally suited for portable electronic devices that are powered from 1-cell Li-ion battery or from other power sources within the range such as cellular phones, PDAs and handy-terminals. Internal synchronous rectifier with low RDS(ON) dramatically reduces conduction loss at PWM mode. The internal synchronous switch increases efficiency while eliminate the need for an external Schottky diode.The switching ripple is easily smoothed-out by small package filtering elements due to a fixed operation frequency TSOT-23-5 of 1.5MHz. This along small with PCB small area package provide ◆ High Efficiency: 93% ◆ 1.5MHz Fixed-Frequency PWM Operation ◆ Adjustable Output From 0.6V to VIN ◆ 1.2V, 1.5V, 1.8V, 2.5V, 2.8V and 3.3V Fixed ◆ 600mA Output Current, 1.1A Peak Current ◆ No Schottky Diode Required ◆ 100% Duty Cycle Low Dropout Operation ◆ Available in TSOT23-5 Package ◆ Short Circuit and Thermal Protection ◆ Over Voltage Protection ◆ Low than 1µA Shutdown CurrentFeaturesApplicationsPortable Media Players/MP3 players Cellular and Smart mobile phone PDA DSC Wireless Cardapplication. Other features include soft start, lower internal reference voltage with 2% accuracy, over temperature protection, and over current protection。
Pin ConfigurationsOrdering InformationLP3203 □ □ □ □ □F: Pb-Free Package Type J5: TSOT23-5 Output Voltage Type A: Adjustable type 12: 1.2V 15: 1.5V 18: 1.8V 25: 2.5VMarking InformationPlease see website.
AMC3100降压芯片DESCRIPTION The AMC3100 is a high efficiency synchronous buck DC/DC converter using a constant frequency, current mode architecture. Adjustable version and fixed output voltages of 1.2V, 1.5V and 1.8V are available. 300uA low supply current at no load and <1µA supply current at shutdown. The 2.5V to 5.5V input voltage range makes the AMC3100 ideally suited for single Li-Ion battery-powered applications. 100% duty cycle provides low dropout operation, extending battery life in portable systems. PWM pulse skipping mode operation provides very low output ripple voltage for noise sensitive applications. Switching frequency is internally set at 1.5MHz, allowing using small surface mount inductors and capacitors. The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode. Low output voltages are easily supported with the 0.6V feedback reference voltage. The AMC3100 is available in a low profile (1mm) Thin SOT-23-5L package. TYPICAL APPLICATIONVOUT＝1.8V / 600mA L VIN＝2.5V to 5.5V VIN SW VOUT1.5MHz, 600mA SYNCHRONOUS STEP-DOWN CONVERTERFEATURES High Efficiency: Up to 96% 600mA Output Current at VIN=3V 2.5V to 5.5V Input Voltage Range 1.5MHz Constant Switching Frequency No Schottky Diode Required 100% Duty Cycle as Low Dropout Operation 0.6V Reference Voltage Allows 0.6V Minimum Output Voltage <1µA Shutdown Mode Supply Current Current Mode Operation for Excellent Line and Load Transient Response Over-temperature Protected 4KV HBM ESD Protection 5-Pin Thin SOT-23 package APPLICATIONS PDA, Personal Media Player Smart Phone Digital Still Camera, Video Camcorder Portable Instruments Bluetooth Headset PACKAGE PIN OUTAMC3100-1.8CIN4.7uFCOUT10uFRUNGNDRUN 1 GND 25VFB / VOUT*A64XSYMBOLIZATION Device Name Output VoltageAMC3100DBFT AMC3100-1.2DBFT AMC3100-1.5DBFT AMC3100-1.8DBFT Adjustable 1.2V Fixed 1.5V Fixed 1.8V FixedSW34 VINMarkingA64A A642 A645 A648TSOT-23-5L ( Top View )* Note: VFB pin for adjustable version. VOUT pin for fixed voltage version.
降压芯片 ETA3486Part Number ETA3486SWICHING FREQUENCY 1.55MHzTemp Range -40°C to +85°COUTPUT VOLTAGE (V) ADJOUTPUT CURRENT (A) 0.8PIN DESCRIPTIONPIN 1 2 3 4 5 NAME EN GND LX VIN FB FUNCTION Chip Enable Pin. Drive RUN above 1.5V to turn on the part. RUN below 0.3V to turn it off. Do not leave RUN floating. Ground Pin Power Switch Output. It is the switch node connection to Inductor. Power Supply Input. Must be closely decoupled to GND with a 4.7µF or greater ceramic capacitor. Output Voltage Feedback Pin. An internal resistive divider divides the output voltage down for comparison to the internal reference voltage. DriveNote 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: TJ is calculated from the ambient temperature TA and power dissipation PD according to the following formula: TJ = TA + (PD) x (250°C/W). Note 3: 100% production test at +25°C. Specifications over the temperature range are guaranteed by design and characterization. Note 4: Dynamic supply current is higher due to the gate charge being delivered at the switching frequency
降压芯片Pin FunctionsHX2772VIN (Pin 1): Main Supply Pin. A 10μF ceramic VIN capacitor recommended must be closely decoupled to GND. GND (Pin 2): Ground Pin. EN (Pin 3): EN Control Input. Forcing this pin above 1.3V enables the part. Forcing this pin below 0.7V can shuts down the device. In shutdown, all functions are disabled drawing <1μA supply current. Do not leave EN floating. VOUT/FB (Pin 4): Feedback Pin. In the nonadjustable version, the output voltage is fixed. In the adjustable version, the output voltage is set by a resistive divider according to the following formula: VOUT = 0.6V • [1 + (R1/R2)]. SW (Pin 5): Switch Node Connection to Inductor. This pin connects to the drains of the internal main and synchronous power MOSFET switches.FUNCTIONAL DESCRIPTIONThe HX2772 is a high performance, 800mA, 1.5MHz monolithic step-down converter. The HX2772 requires only three external power components (CIN, COUT and L). The adjustable version can be programmed with external feedback to any voltage, ranging from 0.6V to the input voltage. At dropout operation, the converter duty cycle increases to 100% and the output voltage tracks the input voltage minus the RDS(ON) drop of the high-side MOSFET. The internal error amplifier and compensation provides excellent transient response, load, and line regulation. Soft start function prevents input inrush current and output overshoot during start up.