Analog Devices

The LT1636 op amp operates on all single and split supplies with a total voltage of 2.7V to 44V drawing less than 50µA of quiescent current. The LT1636 can be shut down, making the output high impedance and reducing the quiescent current to 4µA. The LT1636 has a unique input stage that operates and remains high impedance when above the positive supply. The inputs take 44V both differential and common mode, even when operating on a 3V supply. The output swings to both supplies. Unlike most micropower op amps, the LT1636 can drive heavy loads; its rail-to-rail output drives 18mA. The LT1636 is unity-gain stable into all capacitive loads up to 10,000pF when a 0.22µF and 150Ω compensation network is used.The LT1636 is reverse supply protected: it draws no current for reverse supply up to 27V. Built-in resistors protect the inputs for faults below the negative supply up to 22V. There is no phase reversal of the output for inputs 5V below VEEor 44V above VEE, independent of VCC.The LT1636 op amp is available in the 8-pin MSOP, PDIP and SO packages. For space limited applications the LT1636 available in a 3mm × 3mm × 0.8mm dual fine pitch leadless package (DFN).ApplicationsBattery- or Solar-Powered SystemsPortable InstrumentationSensor ConditioningSupply Current SensingBattery MonitoringMUX Amplifiers4mA to 20mA Transmitters

The LT1637 is a rugged op amp that operates on all single and split supplies with a total voltage of 2.7V to 44V. The LT1637 has a gain-bandwidth product of 1.1MHz while drawing less than 250µA of quiescent current. The LT1637 can be shut down, making the output high impedance and reducing the quiescent current to only 3µA. The LT1637 is reverse supply protected: it draws virtually no current for reverse supply up to 25V. The input range of the LT1637 includes both supplies and the output swings to both supplies. Unlike most micropower op amps, the LT1637 can drive heavy loads; its rail-to-rail output drives 25mA. The LT1637 is unity-gain stable into all capacitive loads up to 4700pF when optional 0.22µF and 150Ω compensation is used.The LT1637 has a unique input stage that operates and remains high impedance when above the positive supply. The inputs take 44V both differential and common mode, even when operating on a 3V supply. Built-in resistors protect the inputs for faults below the negative supply up to 22V. There is no phase reversal of the output for inputs 5V below VEEor 44V above VEE, independent of VCC.The LT1637 op amp is available in the 8-pin MSOP, PDIP and SO packages. For space limited applications, the LT1637 is available in a 3mm × 3mm × 0.8mm dual fine pitch leadless package (DFN).ApplicationsBattery or Solar Powered Systems:Portable InstrumentationSensor ConditioningSupply Current SensingBattery MonitoringMUX Amplifiers4mA to 25mA Transmitters

The LT1638 is a low power dual rail-to-rail input and output operational amplifier available in the standard 8-pin PDIP and SO packages as well as the 8-lead MSOP package. The LT1639 is a low power quad rail-to-rail input and output operational amplifier offered in the standard 14-pin PDIP and surface mount packages. For space limited applications the LT1638 is available in a 3mm × 3mm × 0.8mm dual fine pitch leadless package (DFN).The LT1638/LT1639 op amps operate on all single and split supplies with a total voltage of 2.5V to 44V drawing only 170μA of quiescent current per amplifier. These amplifiers are reverse battery protected and draw no current for reverse supply up to 18V.The input range of the LT1638/LT1639 includes both supplies, and a unique feature of this device is its capability to operate over the top with either or both of its inputs above V+. The inputs handle 44V, both differential and common mode, independent of supply voltage. The input stage incorporates phase reversal protection to prevent false outputs from occurring when the inputs are below the negative supply. Protective resistors are included in the input leads so that current does not become excessive when the inputs are forced below the negative supply. The LT1638/LT1639 can drive loads up to 25mA and still maintain rail-to-rail capability. The op amps are unity-gain stable and drive all capacitive loads up to 1000pF when optional output compensation is used.ApplicationsBattery- or Solar-Powered SystemsPortable InstrumentationSensor ConditioningSupply Current SensingBattery MonitoringMicropower Active Filters4mA to 20mA Transmitters

The LT1638 is a low power dual rail-to-rail input and output operational amplifier available in the standard 8-pin PDIP and SO packages as well as the 8-lead MSOP package. The LT1639 is a low power quad rail-to-rail input and output operational amplifier offered in the standard 14-pin PDIP and surface mount packages. For space limited applications the LT1638 is available in a 3mm × 3mm × 0.8mm dual fine pitch leadless package (DFN).The LT1638/LT1639 op amps operate on all single and split supplies with a total voltage of 2.5V to 44V drawing only 170μA of quiescent current per amplifier. These amplifiers are reverse battery protected and draw no current for reverse supply up to 18V.The input range of the LT1638/LT1639 includes both supplies, and a unique feature of this device is its capability to operate over the top with either or both of its inputs above V+. The inputs handle 44V, both differential and common mode, independent of supply voltage. The input stage incorporates phase reversal protection to prevent false outputs from occurring when the inputs are below the negative supply. Protective resistors are included in the input leads so that current does not become excessive when the inputs are forced below the negative supply. The LT1638/LT1639 can drive loads up to 25mA and still maintain rail-to-rail capability. The op amps are unity-gain stable and drive all capacitive loads up to 1000pF when optional output compensation is used.ApplicationsBattery- or Solar-Powered SystemsPortable InstrumentationSensor ConditioningSupply Current SensingBattery MonitoringMicropower Active Filters4mA to 20mA Transmitters

The LT1640AL/LT1640AH are 8-pin, negative voltage Hot Swap™controllers that allow a board to be safely inserted and removed from a live backplane. Inrush current is limited to a programmable value by controlling the gate voltage of an external N-channel pass transistor. The pass transistor is turned off if the input voltage is less than the programmable undervoltage threshold or greater than the overvoltage threshold. A programmable electronic circuit breaker protects the system against shorts. ThePWRGD(LT1640AL) or PWRGD (LT1640AH) signal can be used to directly enable a power module. The LT1640AL is designed for modules with a low enable input and the LT1640AH for modules with a high enable input.The LT1640AL/LT1640AH are available in 8-pin PDIP and SO packages.ApplicationsCentral Office Switching-48V Distributed Power SystemsNegative Power Supply Control

The LT1641 is an 8-pin Hot Swap™controller that allows a board to be safely inserted and removed from a live backplane. Using an external N-channel pass transistor, the board supply voltage can be ramped up at a programmable rate. A high side switch driver controls an N-channel gate for supply voltages ranging from 9V to 80V.The chip features a programmable analog foldback current limit circuit. If the chip remains in current limit for more than a programmable time, the N-channel pass transistor turns off and is optionally set to automatically restart after a time-out delay.The PWRGD output indicates when the output voltage, sensed by the FB pin, is within tolerance. The ON pin provides programmable undervoltage lockout.The LT1641-1/LT1641-2 are recommended for new designs.The LT1641 is available in the 8-lead SO package.ApplicationsHot Board InsertionElectronic Circuit BreakerIndustrial High Side Switch/Circuit Breaker24V/48V Industrial/Alarm Systems

The LT1671 is a low power 60ns comparator with complementary outputs and latch. The input common mode range extends from 1.5V below the positive supply down to the negative supply rail. Like the LT1394, LT1016 and LT1116, this comparator has complementary outputs designed to interface directly to TTL or CMOS logic. The LT1671 may operate from either a single 5V supply or dual ±5V supplies. Low offset voltage specifications and high gain allow the LT1671 to be used in precision applications.The LT1671 is designed for improved speed and stability for a wide range of operating conditions. The output stage provides active drive in both directions for maximum speed into TTL, CMOS or passive loads with minimal cross-conduction current. Unlike other fast comparators, the LT1671 remains stable even for slow transitions through the active region, which eliminates the need to specify a minimum input slew rate.The LT1671 has an internal, TTL/CMOS compatible latch for retaining data at the outputs. The latch holds data as long as the LATCH pin is held high. Device parameters such as gain, offset and negative power supply current are not significantly affected by variations in negative supply voltage.ApplicationsHigh Speed A/D ConvertersZero-Crossing DetectorsCurrent Sense for Switching RegulatorsExtended Range V/F CovertersFast Pulse Height/Width DiscriminatorsHigh Speed TriggersLine ReceiversHigh Speed Sampling Circuits

The LT1672/LT1673/LT1674 are ultralow power (IS≤ 2µA) decompompensated (AV≥ 5) op amps with precision specifications. The extremely low supply current is combineed with excellent amplifier specifications: input offset voltage is 375µV maximum with atypicaal drift of only 0.4µV/°C, input offset current is 100pA maximum. A minimum open-loop gain (AVOL) of 100V/mV ensures that gain errors are small. The devices' characteristics change little over the supply range of 2.2V to ±15V. Supply rejection is 90dB and the common mode rejection ratio is 90dB. Operation is specified for 3V, 5V and ±15V supplies. Reverse battery protection (-18V min) and inputs that operate above the positive supply make the LT1672/LT1673/LT1674 easy to use in harsh environments.The low bias currents and offset current of the amplifier permit the use of megohm level source resistors without introducing significant errors. Voltage noise at 4µVP-Pis remarkably low considering the low supply current. For unity gain stable versions of these amplifiers, see the LT1494/LT1495/LT1496.The LT1672 is available in the 8-pin MSOP, PDIP and SO packages. The LT1673 is available in plastic 8-pin PDIP and SO-8 packages with the standard dual op amp pinout. The LT1674 is available in 14-pin PDIP and SO packages.ApplicationsBattery- or Solar-Powered SystemsPortable InstrumentationRemote Sensor AmplifierMicropower FilterPhotodiode AmplifierHigh Impedance Circuits