Analog Devices Ltd

The LT®8614 step-down regulator features Silent Switcher architecture designed to minimize EMI/EMC emissions while delivering high efficiency at frequencies up to 3MHz. Assembled in a 3mm × 4mm QFN, the monolithic construction with integrated power switches and inclusion of all necessary circuitry yields a solution with a minimal PCB footprint. An ultralow 2.5ΜA quiescent current-with the output in full regulation- enables applications requiring highest efficiency at very small load currents. Transient response remains excellent and output voltage ripple is below 10mVP-P at any load, from zero to full current. The LT8614 allows high VIN to low VOUT conversion at high frequency with a fast minimum top switch on-time of 30ns. Operation is safe in overload even with a saturated inductor. Essential features are included and easy to use: An opendrain PG pin signals when the output is in regulation. The SYNC pin allows clock synchronization and choice of Burst Mode operation or pulse-skipping mode. Soft-start and tracking functionality is accessed via the TR/SS pin. An accurate enable threshold can be set using the EN/UV pin and a resistor at the RT pin programs switch frequency.

The LT®8697 is a compact, high efficiency, high speed synchronous monolithic step-down switching regulator designed to power 5V USB applications. A precise output voltage and programmable cable drop compensation maintain accurate 5V regulation at the USB socket connected to the end of a long cable. Forced continuous operation allows the LT8697 to sink current, further enhancing accurate 5V regulation during load transients. Accurate and programmable output current limit, a power good indicator pin and an output current monitor pin improve system reliability and safety, allow the user to implement latch-off or auto-retry functionality and can eliminate the need for a USB switch IC. Dual feedback allows regulation on the output of a USB switch and limits cable drop compensation to a maximum of 5.8V output, protecting USB devices during fault conditions. Thermal shutdown provides additional protection by limiting power dissipation in the IC during an overtemperature fault. The LT8697 is available in a small 24-lead 3mm × 5mm package with an exposed pad for low thermal resistance.

The LT®8705 is a high performance buck-boost switching regulator controller that operates from input voltages above, below or equal to the output voltage. The part has integrated input current, input voltage, output current and output voltage feedback loops. With a wide 2.8V to 80V input and 1.3V to 80V output range, the LT8705 is compatible with most solar, automotive, telecom and battery-powered systems. The LT8705 includes servo pins to indicate which feedback loops are active. The MODE pin selects among Burst Mode® operation, discontinuous or continuous conduction mode at light loads. Additional features include a 3.3V/12mA LDO, a synchronizable fixed operating frequency, onboard gate drivers, adjustable UVLO, along with input and output current monitoring with programmable m aximum levels.

The LT®8710 is a synchronous PWM DC/DC controller with a rail-to-rail output current monitor and control. The LT8710 is ideal for many types of power supply topologies and can be easily configured for boost, SEPIC, inverting, or flyback configurations. The LT8710's rail-to-rail output current monitor and control allows the part to be configured in current limited applications such as battery charging. The FLAG pin can be used as a power good indication or C/10 indication allowing for accurate bulk and float battery voltages. The LT8710's switching frequency range can be set between 100kHz and 750kHz using an external resistor or synchronized to an external clock. The LT8710 also features innovative EN/FBIN pin circuitry that allows for slowly varying input signals and an adjustable undervoltage lockout function. The pin is also used for input voltage regulation to avoid collapsing a high impedance input supply. Additional features such as frequency foldback and soft-start are integrated. The LT8710 is available in a 20-lead TSSOP package.

The LTC™1040 is a monolithic CMOS dual comparator manufactured using Linear Technology's enhanced LTCMOS® silicon gate process. Extremely low operating power levels are achieved by internally switching the comparator ON for short periods of time. The CMOS output logic holds the output information continuously while not consuming any power. In addition to switching power ON, a switched output is provided to drive external loads during the comparator's active time. This allows not only low comparator power, but low total system power. Sampling is controlled by an external strobe input or an internal oscillator. The oscillator frequency is set by an external RC network. Each comparator has a unique input structure, giving two differential inputs. The output of the comparator will be high if the algebraic sum of the inputs is positive and low if the algebraic sum of the inputs is negative.

The LTC®1041 is a monolithic CMOS BANG-BANG controller manufactured using Linear Technology's enhanced LTCMOS™ silicon gate process. BANG-BANG loops are characterized by turning the control element fully ON or fully OFF to regulate the average value of the parameter to be controlled. The SET POINT input determines the average control value and the DELTA input sets the deadband. The deadband is always 2 x DELTA and is centered around the SET POINT. Independent control of the SET POINT and deadband, with no interaction, is made possible by the unique sampling input structure of the LTC1041.An external RC connected to the OSC pin sets the sampling rate. At the start of each sample, internal power to the analog section is switched on for approximately 80µs. During this time, the analog inputs are sampled and compared. After the comparison is complete, power is switched off. This achieves extremely low average power consumption at low sampling rates. CMOS logic holds the output continuously while consuming virtually no power.To keep system power at an absolute minimum, a switched power output (VP-P) is provided. External loads, such as bridge networks and resistive dividers, can be driven by this switched output.The output logic sense (i.e., ON = V+) can be reversed (i.e., ON = GND) by interchanging the VIN and SET POINT inputs. This has no other effect on the operation of the LTC1041.

The LTC1042 is a monolithic CMOS window comparator manufactured using Linear Technology's enhanced LTCMOS silicon gate process. Two high impedance voltage inputs, CENTER and WIDTH/2, define the middle and width of the comparison window. Whenever the input voltage, VIN, is inside the window the WITHIN WINDOW output is high. The ABOVE WINDOW output is high whenever VIN is above the window. By interchanging VIN and CENTER, the ABOVE WINDOW output becomes BELOW WINDOW and is high if VIN is below the window. Sampling techniques provide high impedance voltage inputs that can common mode to both supply rails(V+ and GND). An important feature of the inputs is their non-interaction. Also the device is effectively chopper stabilized, giving it extremely high accuracy over all conditions of temperature, power supply and input voltage range. Another benefit of the sampling techniques used to design the LTC1042 is the extremely low power consumption. When the device is strobed, it internally turns on the power to the comparators, samples the inputs, stores the outputs in CMOS latches and then turns off power to the comparators. This all happens in about 80us. Average power can be made small, almost arbitrarily, by lowering the strobe rate. The device can be self-strobed using an external RC network or strobed externally by driving the OSC pin witha CMOS gate.

The LTC™1043 is a monolithic, charge-balanced, dual switched capacitor instrumentation building block. A pair of switches alternately connects an external capacitor to an input voltage and then connects the charged capacitor across an output port. The internal switches have a break-before-make action. An internal clock is provided and its frequency can be adjusted with an external capacitor.The LTC1043 can also be driven with an external CMOS clock. The LTC1043, when used with low clock frequencies, provides ultra precision DC functions without requiring precise external components. Such functions are differential voltage to single-ended conversion, voltage inversion, voltage multiplication and division by 2, 3, 4, 5, etc. The LTC1043 can also be used for precise VµF and FµV circuits without trimming, and it is also a building block for switched capacitor filters, oscillators and modulators. The LTC1043 is manufactured using Linear Technology's enhanced LTCMOS® silicon gate process.

The LTC1044A is a monolithic CMOS switched-capacitor voltage converter. It plugs in for ICL7660/LTC1044 in applications where higher input voltage (up to 12V) is needed. The LTC1044A provides several conversion functions without using inductors. The input voltage can be inverted (VOUT = -VIN), doubled (VOUT = 2VIN), divided (VOUT = VIN/2) or multiplied (VOUT = ±nVIN). To optimize performance in specific applications, a boost function is available to raise the internal oscillator frequency by a factor of 7. Smaller external capacitors can be used in higher frequency operation to save board space. The internal oscillator can also be disabled to save power. The supply current drops to 1.5µA at 5V input when the OSC pin is tied to GND or V + .

The LTC1044 is a monolithic CMOS switched capacitor voltage converter which is manufactured using Linear Technology's enhanced LTCMOSTM silicon gate process. The LTC1044 provides several voltage conversion functions: the input voltage can be inverted (VOUT=-VIN), doubled (VOUT=2 VIN), divided (VOUT=VIN/2) or multiplied (VOUT=?nVIN). Designed to be pin-for-pin and functionally compatible with the popular 7660, the LTC1044 provides significant features and improvements over earlier 7660 designs. These improvements include: full 1.5V to 9V supply operation over the entire operating temperature range, without the need for external protection diodes; 21/2 times lower quiescent current for greater power conversion efficiency; and a "boost" function which is available to raise the internal oscillator frequency to optimize performance in specific applications. Although the LTC1044 provides significant design and performance advantages over the earlier 7660 device, it still maintains its still maintains its compatibility with existing 7660 designs.