LT1945Dual Micropower DC/DC Converter with Positive and Negative Outputs | PMIC | 4 | Active | The LT1945 is a dual micropower DC/DC converter in a 10-pin MSOP package. Each converter is designed with a 350mA current limit and an input voltage range of 1.2V to 15V, making the LT1945 ideal for a wide variety of applications. Both converters feature a quiescent current of only 20µA at no load, which further reduces to 0.5µA in shutdown. A current limited, fixed off-time control scheme conserves operating current, resulting in high efficiency over a broad range of load current. The 36V switch allows high voltage outputs up to ±34V to be easily generated without the use of costly transformers. The LT1945’s low off-time of 400ns permits the use of tiny, low profile inductors and capacitors to minimize footprint and cost in space-conscious portable applications.ApplicationsSmall TFT LCD PanelsHandheld ComputersBattery BackupDigital Cameras |
| PMIC | 4 | Active | |
LT1946A2.7MHz Boost DC/DC Converter with 1.5A Switch and Soft-Start | Power Management (PMIC) | 2 | Active | The LT1946A is a fixed frequency step-up DC/DC converter containing an internal 1.5A, 36V switch. Capable of generating 12V at 430mA from a 5V input, the LT1946A is ideal for powering large TFT-LCD panels. The LT1946A switches at 2.7MHz, allowing the use of tiny, low profile inductors and low value ceramic capacitors. Loop compensation can be either internal or external, giving the user flexibility in setting loop compensation and allowing optimized transient response with low ESR ceramic output capacitors. Soft-start is controlled with an external capacitor which determines the input current ramp rate during start up. The 8-lead MSOP package and high switching frequency ensure a low profile overall solution less than 1.1mm high.Switching FrequencyLT19461.2MHzLT1946A2.7MHzApplicationsTFT-LCD Bias SuppliesGPS ReceiversDSL ModemsLocal Power Supply |
| Integrated Circuits (ICs) | 4 | Active | |
LT1949600kHz, 1A Switch PWM DC/DC Converter | Voltage Regulators - DC DC Switching Regulators | 6 | Active | The LT1949 is a fixed frequency step-up DC/DC converter with a 1A, 0.5Ω internal switch. Capable of generating 10V at 175mA from a 3.3V input, the LT1949 is ideal for generating bias voltages for large screen LCD panels. Constant frequency 600kHz operation results in a low noise output that is easy to filter and the 30V switch rating allows output voltage up to 28V using a single inductor. An external compensation pin gives the user flexibility in optimizing loop compensation, allowing small low ESR ceramic capacitors to be used at the output. The 8-lead MSOP and SO packages ensure a low profile overall solution.The LT1949 includes a low-battery detector that stays alive when the device goes into shutdown. Quiescent current in shutdown is 25µA, while operating current is 4.5mA.ApplicationsLCD Bias SuppliesGPS ReceiversBattery BackupPortable Electronic EquipmentDiagnostic Medical Instrumentation |
| PMIC | 4 | Active | |
LT1952Single Switch Synchronous Forward Controller | Voltage Regulators - DC DC Switching Controllers | 13 | Active | The LT1952/LT1952-1 are current mode PWM controllers optimized to control the forward converter topology, using one primary MOSFET. The LT1952/LT1952-1 provide synchronous rectifier control, resulting in extremely high efficiency. A programmable Volt-Second clamp provides a safeguard for transformer reset that prevents saturation. This allows a single MOSFET on the primary side to reliably run at greater than 50% duty cycle for high MOSFET, transformer and rectifier utilization. The devices include soft-start for controlled exit from shutdown and undervoltage lockout. A precision 107mV current limit threshold, independent of duty cycle, combines with softstart to provide hiccup short circuit protection. The LT1952 is optimized for micropower bootstrap startup from high input voltages. The LT1952-1 allows startup from lower input voltages. Programmable slope compensation and leading edge blanking allow optimization of loop bandwidth with a wide range of inductors and MOSFETs. Each device can be programmed over a 100kHz to 500kHz frequency range and the part can be synchronized to an external clock. The error amplifier is a true op amp, allowing a wide range of compensation networks. The LT1952/LT1952-1 are available in a small 16-pin SSOP package.ApplicationsTelecommunications Power SuppliesIndustrial and Distributed PowerIsolated and Non-Isolated DC/DC Converters |
| PMIC | 16 | Active | |
| PMIC | 8 | Active | |
LT19611.5A, 1.25MHz Step-Up Switching Regulator | Power Management (PMIC) | 4 | Active | The LT1961 is a 1.25MHz monolithic boost switching regulator. A high efficiency 1.5A, 0.2Ω switch is included on the die together with all the control circuitry required to complete a high frequency, current-mode switching regulator. Current-mode control provides fast transient response and excellent loop stability.New design techniques achieve high efficiency at high switching frequencies over a wide operating voltage range. A low dropout internal regulator maintains consistent performance over a wide range of inputs from 24V systems to Li-Ion batteries. An operating supply current of 1mA maintains high efficiency, especially at lower output currents. Shutdown reduces quiescent current to 6µA. Maximum switch current remains constant at all duty cycles. Synchronization allows an external logic level signal to increase the internal oscillator from 1.5MHz to 2MHz.The LT1961 is available in an exposed pad, 8-pin MSOP package. Full cycle-by-cycle switch current limit protection and thermal shutdown are provided. High frequency operation allows the reduction of input and output filtering components and permits the use of chip inductors.ApplicationsDSL ModemsPortable ComputersBattery-Powered SystemsDistributed Power |
