LINEAR Manuals

The LTC4412 is a low-loss PowerPathTM controller that replaces traditional low-voltage OR’ing diodes, has minimal external components, automatic switching between DC sources, load sharing, low quiescent current, and is suitable for mobile phones, notebook computers, digital cameras, USB peripherals, UPS and other applications.

LTC1733 is a single-chip lithium-ion battery constant-current/constant-voltage linear charger with an on-chip power MOSFET. Internal thermal feedback regulates the charge current to limit die temperature during high power operation or high ambient temperature conditions. No external current sense resistor is needed and no blocking diode is required due to the internal MOSFET architecture. The charge current and charge time can be set externally with a single resistor and capacitor.

The LT3023 is a dual, micropower, low noise, low dropout regulator. It can provide 100mA of output current with a dropout voltage of 300mV. Its quiescent current is 20μA and its shutdown current is less than 0.1μA.

LT1078/LT1079 are micropower, dual and quad, single supply, precision op amps. They feature low supply current, low offset voltage, and low noise.

The LT4250L/LT4250H is a negative 48V hot swap controller that allows a board to be safely inserted and removed from a live backplane. By controlling the gate voltage of an external N-channel pass transistor, inrush current is limited to a programmable value. If the input voltage is less than the programmable undervoltage threshold or greater than the overvoltage threshold, the pass transistor is turned off. A programmable current limit protects the system against shorts. After a 500µs timeout, the current limit activates the electronic circuit breaker. The PWRGD (LT4250L) or PWRGD (LT4250H) signal can be used to directly enable a power module. The LT4250L is designed for modules with a low enable input and the LT4250H for modules with a high enable input. The LT4250L/LT4250H are available in 8-pin PDIP and SO packages.

The LTM4602 is a 6A high efficiency DC/DC step-down power supply, suitable for telecom and networking equipment, servers, industrial equipment, etc.

This document introduces the LTC3831, a high power, high efficiency DDR memory termination switching regulator controller. The device uses a synchronous switching architecture with N-channel MOSFETs, and the output voltage is equal to 1/2 of the external supply or reference voltage. The LTC3831 can sense output current and regulate it through the drain-source resistance of the upper N-channel MOSFET, thereby providing adjustable current limit without a current sense resistor. The device can operate with a supply voltage as low as 3V and with a maximum duty cycle of >91%. It includes a fixed frequency PWM oscillator for low output ripple operation.

LT3012 is a high voltage, micropower, low dropout linear regulator. The device is capable of supplying 250mA of output current with a dropout voltage of 400mV. Designed for use in battery-powered or high voltage systems, the low quiescent current (operating 40µA, shutdown 1µA) makes the LT3012 an ideal choice. Quiescent current is also well controlled in dropout. Other features of the LT3012 include the ability to operate with very small output capacitors. The regulator is stable with only 3.3µF on the output while most older devices require between 10µF and 100µF for stability. Small ceramic capacitors can be used without any need for series resistance (ESR) as is common with other regulators. Internal protection circuitry includes reverse-battery protection, current limiting, thermal limiting and reverse current protection. The device is available with an adjustable output with a 1.24V reference voltage. The LT3012 regulator is available in the 16-lead TSSOP and 12 pin low profile (0.75mm) (4mm × 3mm) DFN packages with an exposed pad for enhanced thermal handling capability.

The LTC1153 is an auto-reset electronic circuit breaker with programmable trip delay, trip current and auto-reset time, which can drive low RDS(ON) N-channel MOSFETs and achieve thermal action via PTC thermistor.

The LTC6240/6241/LTC6242 series are low noise, low offset, unity gain stable CMOS op amps featuring 1pA of input bias current. Input bias current is guaranteed to be 1pA max on the single LTC6240. The 0.1Hz to 10Hz noise of only 550nVP-P, along with an offset of just 125µV are significant improvements over traditional CMOS op amps. Additionally, noise is guaranteed to be less than 10nV/√Hz at 1kHz. An 18MHz gain bandwidth, and 10V/µs slew rate, along with the wide supply range and low input capacitance, make them perfect for use as fast signal processing amplifiers. These op amps have an output stage that swings within 30mV of either supply rail to maximize the signal dynamic range in low supply applications. The input common mode range extends to the negative supply. They are fully specified on 3V and 5V, and an HV version guarantees operation on supplies up to ±5V. The LTC6240 is available in the 8-pin SO and the 5-pin SOT-23 packages. The LTC6241 is available in the 8-pin SO, and for compact designs it is packaged in a tiny dual fine pitch leadless (DFN) package. The LTC6242 is available in the 16-Pin SSOP as well as the 5mm × 3mm DFN package.

The document introduces the LTC3713 low input voltage, high power, No RSENSE synchronous buck DC/DC controller. The controller adopts true current mode control, the input voltage can be as low as 1.5V, without 5V auxiliary power supply, using standard 5V logic level N-channel MOSFETs, adjustable current limit, frequency, switch time, duty cycle, reference voltage, output overvoltage protection, etc., suitable for telecom card 3.3V, 2.5V, 1.8V step-down, bus termination (DDR memory, SSTL), synchronous buck with general purpose boost, low VIN synchronous boost and other applications.

LT6700-1/LT6700-2/LT6700-3/LT6700HV-1/LT6700HV-2/LT6700HV-3 are low power, low voltage, dual comparators with a 400mV reference in a 6-lead SOT-23 or tiny DFN package. Operating with supplies from 1.4V up to 18V, these devices draw only 6.5μA, making them ideal for low voltage system monitoring. Hysteresis is included in the comparators, easing design requirements to insure stable output operation. The comparators each have one input available externally; the other inputs are connected internally to the reference. The comparator outputs are open collector and the output load can be referred to any voltage up to 18V (36V for LT6700HV), independent of supply voltage. The output stage sinking capability is guaranteed to be greater than 5mA over temperature. The three versions of this part differ by the polarity of the available comparator inputs. The LT6700-1/LT6700HV-1 has one inverting input and one noninverting input, making it suitable for use as a window comparator. The LT6700-2/LT6700HV-2 has two inverting inputs and the LT6700-3/LT6700HV-3 has two noninverting inputs. All versions are offered in commercial, industrial and automotive temperature ranges.

The LTC1487 is an ultra-low power differential line transceiver designed with high impedance inputs allowing up to 256 transceivers to share a single bus. It meets the requirements of RS485 and RS422. The LTC1487 features output drivers with controlled slew rate, decreasing the EMI radiated from the RS485 lines, and improving signal fidelity with misterminated lines. The CMOS design offers significant power savings without sacrificing ruggedness against overload or ESD damage. Typical quiescent cur- rent is only 80µA while operating and 1µA in shutdown. The driver and receiver feature three-state outputs, with the driver outputs maintaining high impedance over the entire common-mode range. Excessive power dissipation caused by bus contention or faults is prevented by a thermal shutdown circuit which forces the driver outputs into a high impedance state. The receiver has a fail-safe feature which guarantees a high output state when the inputs are left open. I/O pins are protected against multiple ESD strikes of over ±10kV using the Human Body Model. The LTC1487 is fully specified over the commercial tem- perature range and is available in 8-pin DIP and SO packages.

The LT6013/LT6014 is a single/dual 145µA, 9.5nV/√Hz, AV≥5, rail-to-rail output precision op amp. It features low noise, high precision input performance, low power consumption and rail-to-rail output swing. The amplifier is stable in a gain of 5 or more and features greatly improved CMRR and PSRR versus frequency compared to other precision op amps. Input offset voltage is factory-trimmed to less than 35µV. The low drift and excellent long-term stability ensure a high accuracy over temperature and time. The 250pA maximum input bias current and 145µA supply current make this amplifier very suitable for battery-powered precision systems and low-voltage precision systems. It can be used for thermocouple amplifiers, precision photodiode amplifiers, instrumentation amplifiers, micro-power sensor interfaces and other applications.

The LT1884/LT1885 op amps provide high accuracy input performance to amplifiers with rail-to-rail output swing and faster response compared to other precision amplifiers. The input offset voltage is trimmed to less than 50µV, and the low drift ensures accuracy over the operating temperature range. The maximum input bias currents are ultralow at 400pA. The amplifiers can operate on any total power supply voltage between 2.7V and 36V (fully specified from 5V to ±15V). The output voltage swings to within 40mV of the negative supply and 220mV of the positive supply, making them suitable for low voltage single supply operation. With a supply current of less than 1mA per amplifier, they offer superior response and settling time performance in a low power precision amplifier. The dual LT1884 is available in 8-pin SO and PDIP packages with standard pinouts. The quad LT1885 is also available in the standard pinout 14-pin SO package.