Microprocessor Supervisory Circuit

The LTM4652 is a source/sink dual ±25A or single ±50A output switching mode step-down DC/DC μModule® (micromodule) regulator with ±1.5% total DC output error. Included in the package are the switching controllers, power MOSFETs, inductors and all supporting components. Operating from an input voltage range of 4.5V to 18V, the LTM4652 supports two outputs with an output voltage range of 0.6V to 7.5V, each set by a single external resistor. Its high efficiency design delivers up to ±25A continuous current for each output. Only a few input and output capacitors are needed. Adjustable control loop compensation allows for fast transient response to minimize output capacitance when powering FPGAs, ASICs, and processors.Fault protection features include input and output overvoltage and bidirectional overcurrent protection. The LTM4652 is offered in a 16mm × 16mm × 4.92mm BGA package.APPLICATIONS Test and Measurement Instrumentation Telecom and Networking Equipment Industrial Equipment

The ADM1169 Super Sequencer® is a configurable supervisory/ sequencing device that offers a single-chip solution for supply monitoring and sequencing in multiple supply systems. In addition to these functions, the ADM1169 integrates a 12-bit ADC and four 8-bit voltage output DACs. These circuits can be used to implement a closed-loop margining system that enables supply adjustment by altering either the feedback node or reference of a dc-to-dc converter using the DAC outputs. Supply margining can be performed with a minimum of external components. The margining loop can be used for in-circuit testing of a board during production (for example, to verify board functionality at –5% of nominal supplies), or it can be used dynamically to accurately control the output voltage of a dc-to-dc converter. The device also provides up to eight programmable inputs for monitoring undervoltage faults, overvoltage faults, or out-of-window faults on up to eight supplies. In addition, there are eight programmable outputs that can be used as logic enables. Six of these programmable outputs can also provide up to a 12 V output for driving the gate of an N-FET that can be placed in the path of a supply. The logical core of the device is a sequencing engine (SE). This state machine-based construction provides up to 63 different states. This design enables very flexible sequencing of the outputs, based on the condition of the inputs. A block of nonvolatile EEPROM is available that can be used to store user-defined information and may also be used to hold a number of fault records that are written by the sequencing engine defined by the user when a particular fault or sequence occurs. The ADM1169 is controlled via configuration data that can be programmed into an EEPROM. The entire configuration can be programmed using an intuitive GUI-based software package provided by Analog Devices, Inc.

The ADM1275 is a hot-swap controller that allows a circuit board to be removed from or inserted into a live backplane. It also features current and voltage readback via an integrated 12-bit analog-to-digital converter (ADC), accessed using a PMBus™ interface. The load current is measured using an internal current sense amplifier that measures the voltage across a sense resistor in the power path via the SENSE+ and SENSE− pins. A default limit of 20 mV is set, but this limit can be adjusted, if required, using a resistor divider network from the internal reference voltage to the ISET pin.The ADM1275 limits the current through the sense resistor by controlling the gate voltage of an external N-channel FET in the power path, via the GATE pin. The sense voltage—and, therefore, the load current—is maintained below the preset maximum. The ADM1275 protects the external FET by limiting the time that the FET remains on while the current is at its maximum value. This current limit time is set by the choice of capacitor connected to the TIMER pin. In addition, a foldback resistor network can be used to actively lower the current limit as the voltage across the FET is increased. This helps to maintain constant power in the FET and allows the safe operating area (SOA) to be adhered to in an effective manner.In case of a short-circuit event, a fast internal overcurrent detector responds within 370 ns and signals the gate to shut down. A 1500 mA pull-down device ensures a fast FET response. The ADM1275 features overvoltage and undervoltage protection, programmed using external resistor dividers on the UV and OV pins. A PWRGD signal can be used to detect when the output supply is valid, using the FLB pin to monitor the output. GPO pins can be configured as various output signals that can be asserted when a programmed current or voltage level is reached.The 12-bit ADC can measure the current in the sense resistor, as well as the supply voltage on the SENSE+ pin or the output voltage. A PMBus interface allows a controller to read current and voltage data from the ADC. Measurements can be initiated by a PMBus command. Alternatively, the ADC can run continuously, and the user can read the latest conversion data whenever required. Up to four unique PMBus addresses can be selected, depending on the way that the ADR pin is connected. The ADM1275-1 and ADM1275-3 are available in a 20-lead QSOP and 20-lead LFCSP and have a LATCH pin that can be configured for automatic retry or latch-off when an overcurrent fault occurs. The ADM1275-2 is available in a 16-lead QSOP with latch-off mode only.Applications Power monitoring and control/power budgeting Central office equipment Telecommunication and data communication equipment PCs/servers

The ADM6326/ADM6328/ADM6346/ADM6348 devices provide low cost solutions for protecting sensitive circuitry, such as micro-processor and telecommunications circuitry.With built-in glitch immunity, ultralow supply currents, and 24 reset threshold voltage options, the ADM6326/ADM6328/ADM6346/ADM6348 not only ensure that systems are immune to fast transients on VCC, but also that the devices are suitable for monitoring a variety of supply voltages in low power, portable equipment.These devices provide a reset output during power-up, power-down, and brownout conditions. On power-up, an internal timer holds RESET asserted for at least 100 ms. This holds the microprocessor in a reset state until conditions have stabilized. The reset output remains operational with VCC as low as 1 V.The ADM6326 and ADM6346 have an active low push-pull reset output. The ADM6328 and ADM6348 have an active low open-drain reset output, which requires an external pull-up resistor. The ADM6326 and ADM6328 offer a choice of ten reset thresholds in increments between 2.2 V and 3.08 V, whereas the ADM6346 and ADM6348 offer a choice of 14 reset thresholds between 3.3 V and 4.63 V. Not all options are released for sale as standard models. See the Ordering Guide for details.These devices are available in a 3-lead SOT-23 package and operate over the extended temperature range of −40°C to +85°C.Applications Telecommunications Microprocessor systems Desktop and notebook computers Portable equipment

The ADM6326/ADM6328/ADM6346/ADM6348 devices provide low cost solutions for protecting sensitive circuitry, such as micro-processor and telecommunications circuitry.With built-in glitch immunity, ultralow supply currents, and 24 reset threshold voltage options, the ADM6326/ADM6328/ADM6346/ADM6348 not only ensure that systems are immune to fast transients on VCC, but also that the devices are suitable for monitoring a variety of supply voltages in low power, portable equipment.These devices provide a reset output during power-up, power-down, and brownout conditions. On power-up, an internal timer holds RESET asserted for at least 100 ms. This holds the microprocessor in a reset state until conditions have stabilized. The reset output remains operational with VCC as low as 1 V.The ADM6326 and ADM6346 have an active low push-pull reset output. The ADM6328 and ADM6348 have an active low open-drain reset output, which requires an external pull-up resistor. The ADM6326 and ADM6328 offer a choice of ten reset thresholds in increments between 2.2 V and 3.08 V, whereas the ADM6346 and ADM6348 offer a choice of 14 reset thresholds between 3.3 V and 4.63 V. Not all options are released for sale as standard models. See the Ordering Guide for details.These devices are available in a 3-lead SOT-23 package and operate over the extended temperature range of −40°C to +85°C.Applications Telecommunications Microprocessor systems Desktop and notebook computers Portable equipment

The ADM6326/ADM6328/ADM6346/ADM6348 devices provide low cost solutions for protecting sensitive circuitry, such as micro-processor and telecommunications circuitry.With built-in glitch immunity, ultralow supply currents, and 24 reset threshold voltage options, the ADM6326/ADM6328/ADM6346/ADM6348 not only ensure that systems are immune to fast transients on VCC, but also that the devices are suitable for monitoring a variety of supply voltages in low power, portable equipment.These devices provide a reset output during power-up, power-down, and brownout conditions. On power-up, an internal timer holds RESET asserted for at least 100 ms. This holds the microprocessor in a reset state until conditions have stabilized. The reset output remains operational with VCC as low as 1 V.The ADM6326 and ADM6346 have an active low push-pull reset output. The ADM6328 and ADM6348 have an active low open-drain reset output, which requires an external pull-up resistor. The ADM6326 and ADM6328 offer a choice of ten reset thresholds in increments between 2.2 V and 3.08 V, whereas the ADM6346 and ADM6348 offer a choice of 14 reset thresholds between 3.3 V and 4.63 V. Not all options are released for sale as standard models. See the Ordering Guide for details.These devices are available in a 3-lead SOT-23 package and operate over the extended temperature range of −40°C to +85°C.Applications Telecommunications Microprocessor systems Desktop and notebook computers Portable equipment

The ADM6326/ADM6328/ADM6346/ADM6348 devices provide low cost solutions for protecting sensitive circuitry, such as micro-processor and telecommunications circuitry.With built-in glitch immunity, ultralow supply currents, and 24 reset threshold voltage options, the ADM6326/ADM6328/ADM6346/ADM6348 not only ensure that systems are immune to fast transients on VCC, but also that the devices are suitable for monitoring a variety of supply voltages in low power, portable equipment.These devices provide a reset output during power-up, power-down, and brownout conditions. On power-up, an internal timer holds RESET asserted for at least 100 ms. This holds the microprocessor in a reset state until conditions have stabilized. The reset output remains operational with VCC as low as 1 V.The ADM6326 and ADM6346 have an active low push-pull reset output. The ADM6328 and ADM6348 have an active low open-drain reset output, which requires an external pull-up resistor. The ADM6326 and ADM6328 offer a choice of ten reset thresholds in increments between 2.2 V and 3.08 V, whereas the ADM6346 and ADM6348 offer a choice of 14 reset thresholds between 3.3 V and 4.63 V. Not all options are released for sale as standard models. See the Ordering Guide for details.These devices are available in a 3-lead SOT-23 package and operate over the extended temperature range of −40°C to +85°C.Applications Telecommunications Microprocessor systems Desktop and notebook computers Portable equipment

The ADP122 / ADP123 are low quiescent current, low dropoutlinear regulators. They are designed to operate from an inputvoltage between 2.3 V and 5.5 V and to provide up to 300 mA of output current. The low 85 mV dropout voltage at a 300 mA loadimproves efficiency and allows operation over a wide inputvoltage range.The low 170 μA of quiescent current at full load makes the ADP122ideal for battery-operated portable equipment.The ADP122 is capable of 31 fixed output voltages from 1.75 Vto 3.3 V. The ADP123 is the adjustable version of the device andallows the output voltage to be set between 0.8 V and 5.0 V by an external voltage divider.The ADP122 / ADP123 are specifically designed for stable operationwith tiny 1 μF ceramic input and output capacitors to meet therequirements of high performance, space constrained applications.The ADP122 / ADP123 have an internal soft start that gives aconstant start-up time of 350 μs. Short-circuit protection andthermal overload protection circuits prevent damage in adverse conditions. The ADP122 / ADP123 are available in a tiny, 5-leadTSOT package and 6-lead LFCSP package for the smallestfootprint solution to meet a variety of portable applications.APPLICATIONS Digital camera and audio devices Portable and battery-powered equipment Automatic meter reading (AMR) meters GPS and location management units Medical instrumentation Point-of-sale equipment

The ADP124 / ADP125 are low quiescent current, low dropout linear regulators. They are designed to operate from an input voltage between 2.3 V and 5.5 V and to provide up to 500 mA of output current. The low 130 mV dropout voltage at a 500 mA load improves efficiency and allows operation over a wide input voltage range.The low 210 μA of quiescent current with a 500 mA load makes the ADP124 / ADP125 ideal for battery-operated portable equipment.The ADP124 is capable of 31 fixed-output voltages from 1.75 V to 3.3 V. The ADP125 is the adjustable version of the device and allows the output voltage to be set between 0.8 V and 5.0 V by an external voltage divider.The ADP124/ADP125 are specifically designed for stable operation with tiny 1 μF ceramic input and output capacitors to meet the requirements of high performance, space constrained applications.The ADP124 / ADP125 have an internal soft start that gives a constant start-up time of 350 μs. Short-circuit protection and thermal overload protection circuits prevent damage in adverse conditions. The ADP124 / ADP125 are available in an 8-lead exposed paddle MSOP package. When compared with the standard MSOP package, the exposed paddle MSOP package has lower thermal resistance (θJA). The lower thermal resistance package allows the ADP124 / ADP125 to meet the needs of a variety of portable applications while minimizing the rise in junction temperature.APPLICATIONS Digital camera and audio devices Portable and battery-powered equipment Automatic meter reading (AMR) meters GPS and location management units Medical instrumentation Point of load power