LINEAR Manuals

1 LT1424-9 SN14249 14249FS 9V output isolated flyback switching regulator, no transformer "third winding" or opto-isolator required, application circuit meets PCMCIA Type II height requirement, fixed, application specific 9V output voltage, regulation maintained well into discontinuous mode (light load), load compensation provides excellent load regulation, available in 8-pin PDIP and SO packages, operating frequency: 285kHz. The LT ®1424-9 is a monolithic high power switching regulator specifically designed for the isolated flyback topology. No "third winding" or opto-isolator is required; the integrated circuit senses the isolated output voltage directly from the primary side flyback waveform. A high current, high efficiency switch is included on the die along with all oscillator, control and protection circuitry. The LT1424-9 operates with input supply voltages from 3V to 20V and draws only 7mA quiescent current. It can deliver up to 200mA at 9V with no external power devices. By utilizing current mode switching techniques, it pro- vides excellent AC and DC line regulation. The LT1424-9 has a number of features not found on other switching regulator ICs. Its unique control circuitry can maintain regulation well into discontinuous mode. Load compensation circuitry allows for improved load regula- tion. An externally activated shutdown mode reduces total supply current to 20µA typical for standby operation. -9V PCMCIA Type II Isolated LAN Supply (2.41mm Maximum Height).

The LT1461 is a family of low dropout micropower bandgap references that combine very high accuracy and low drift with low supply current and high output drive. These series references use advanced curvature compensation techniques to obtain low temperature coefficient and trimmed precision thin-film resistors to achieve high output accuracy. The LT1461 family draws only 35µA of supply current, making them ideal for low power and portable applications, however their high 50mA output drive makes them suitable for higher power requirements, such as precision regulators. In low power applications, a dropout voltage of less than 300mV ensures maximum battery life while maintaining full reference performance. Line regulation is nearly immeasur- able, while the exceedingly good load and thermal regulation will not add significantly to system error budgets. The shutdown feature can be used to switch full load currents and can be used for system power down. Thermal shutdown protects the part from overload conditions.

The LTC1698 is a precision secondary-side forward converter controller that synchronously drives external N-channel MOSFETs. It is designed for use with the LT3781 primary-side synchronous forward converter controller to create a completely isolated power supply. The LT3781 synchronizes the LTC1698 through a small pulse transformer and the LTC1698 drives a feedback optocoupler to close the feedback loop. Output accuracy of ±0.8% and high efficiency over a wide range of load currents are obtained. The LTC1698 provides accurate secondary-side current limit using an external current sense resistor. The input voltage at the MARGIN pin provides ±5% output voltage adjustment. A power good flag and overvoltage input are provided to ensure proper power supply conditions. An auxiliary 3.3V logic supply is included that supplies up to 10mA of output current.

LTC3448 3448f is a high efficiency synchronous step-down regulator with optional linear regulator mode. It has 1.5MHz or 2.25MHz switching frequency and 600mA output current. It supports low output voltage.

The LTC1564 is a new type of continuous time filter for antialiasing, reconstruction and other band-limiting applications. It has one analog input pin and one analog output pin. The cutoff frequency (fC) and gain are programmable while the shape of the lowpass response is fixed. A latching digital interface stores fC and gain settings or it can be bypassed for control directly from the pins. The LTC1564 operates from 2.7V to 10V total (single or split supplies) and comes in a 16-pin surface mount package.

The LTM4600HV is a high-efficiency 10A DC/DC µModule suitable for applications with an input voltage range of 4.5V to 28V and an output voltage range of 0.6V to 5V. This product adopts a high switching frequency and an adaptive on-time current mode architecture, enabling a very fast transient response to line and load changes. Fault protection features include integrated overvoltage and short circuit protection with a defeatable shutdown timer. The product also features a built-in soft-start timer that can be adjusted with a small capacitor. The LTM4600HV is packaged in a low-profile package, allowing for high-density point-to-point regulation using unused space on the bottom of the PCB.

The LT3011 is a high voltage, micropower, low dropout linear regulator. The device is capable of supplying 50mA of output current with a dropout voltage of 300mV. Designed for use in battery-powered high voltage systems, the low quiescent current (46μA operating and 1μA in shutdown) is well controlled in dropout, making the LT3011 an ideal choice. The LT3011 includes a PWRGD flag to indicate output regulation. The delay between regulated output level and flag indication is programmable with a single capacitor. The LT3011 also has the ability to operate with very small output capacitors; it is stable with only 1μF on the output. Small ceramic capacitors can be used without the addition of any series resistance (ESR) as is common with other products.

This document introduces LT1680, a high-power, current-mode switching power supply controller optimized for boost topologies. The IC drives an N-channel MOSFET switch for DC/DC converter applications up to 60V input. A high current gate drive output handles up to 10,000pF gate capacitance, enabling the construction of high power DC/DC convert- ers. Current sense common mode range up to 60V allows current sensing to be referenced to the input supply, eliminating the need for sense blanking circuits. The LT1680 incorporates programmable average current limiting allowing accurate limiting of DC current in the magnetics, independent of ripple current . User adjustable slope compensation provides stable operation at duty cycles up to 90%. The LT1680 operating frequency is programmable and can be synchronized up to 200kHz. Minimum off-time operation provides switch protection. The IC also incorpo- rates a soft start feature that is gated by both shutdown and undervoltage lockout conditions.

This is a 1.25MHz step-down switching regulator with high efficiency, low dropout voltage and low static current

The LTC1325 is a microprocessor-controlled battery management system that features fast charging, flexible current regulation, battery voltage, temperature, and charge time fault protection, etc.

The LT1158 is a half-bridge N-channel power MOSFET driver that drives the gate of the top MOSFET above V+. It operates at supply voltages from 5V to 30V, with 150ns transition times driving 3000pF. It has a peak driver current of over 500mA, adaptive non-overlap gate drives, continuous current limit protection, automatic shutdown and retry capability, a built-in charge pump for DC operation, built-in gate voltage protection, and is compatible with current-sensing MOSFETs. It has TTL/CMOS input levels and a fault output indication.

The LTC3736 is a 2-phase dual synchronous step-down switching regulator controller with tracking that drives external complementary power MOSFETs using few exter- nal components. The constant frequency current mode architecture with MOSFET VDS sensing eliminates the need for sense resistors and improves efficiency. Power loss and noise due to the ESR of the input capacitance are significantly reduced.

The LTC1745 is a low noise, 12-bit, 25Msps ADC with selectable input ranges, low power dissipation, and high performance. It is suitable for applications such as telecommunications, medical imaging, receivers, cellular base stations, spectrum analysis, and imaging systems.

The LT ®1316 is a micropower step-up DC/DC converter that operates from an input voltage as low as 1.5V. A programmable input current limiting function allows pre- cise control of peak switch current. Peak switch current can be set to any value between 30mA and 500mA by adjusting one resistor. This is particularly useful for DC/DC converters operating from high source impedance inputs such as lithium coin cells or telephone lines. The fixed off-time, variable on-time regulation scheme results in quiescent current of only 33µA in active mode. Quiescent current decreases to 3µA in shutdown with the low-battery detector still active. The LT1316 is available in 8-lead MSOP and SO packages.

The LT ®1635 is a new analog building block that includes a rail-to-rail output op amp, a precision reference and reference buffer. The device operates from supplies as low as a single 1.2V or up to ±5V, yet it consumes only 130µA of supply current. The input common mode range of the op amp includes ground and incorporates phase reversal protection to pre- vent false outputs from occurring when the input is below the negative supply. The rail-to-rail output stage can swing to within 15mV of each rail with no load and can swing to within 250mV of each rail while delivering 10mA of output current. The gain bandwidth of the op amp is 175kHz and it is unity- gain stable with up to 1000pF load capacitance. The 0.2V reference is referred to V– and includes a buffer amplifier to enhance flexibility. The reference and buffer combine to achieve a drift of 30ppm/°C, a line regulation of 20ppm/V and a load regulation of 150ppm/mA. The LT1635 is available in 8-pin PDIP and SO packages, and has the industry standard LM10 pinout.