The MAX690 family of supervisory circuits reduces the complexity and number of components required for power supply monitoring and battery control functions in microprocessor systems. These include µP reset and backup-battery switchover, watchdog timer, CMOS RAM write protection, and power-failure warning. The MAX690 family significantly improves system reliability and accu- racy compared to that obtainable with separate ICs or discrete components.The MAX690, MAX692, and MAX694 are supplied in 8-pin packages and provide four functions: A reset output during power-up, power-down, and brownout conditions.Battery backup switching for CMOS RAM, CMOS microprocessor or other low power logic.A Reset pulse if the optional watchdog timer has not been toggled within a specified time. A 1.3V threshold detector for power fail warning, low battery detection, or to monitor a power supply other than +5V.The MAX691, MAX693, and MAX695 are supplied in 16-pin packages and perform all MAX690, MAX692, MAX694 functions, plus: Write protection of CMOS RAM or EEPROM. Adjustable reset and watchdog timeout periods. Separate outputs for indicating a watchdog timeout, backup-battery switchover, and low VCC.ApplicationsAutomotive SystemsComputersControllersCritical µP Power MonitoringIntelligent Instruments

The ADM1062 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 ADM1062 integrates a 12-bit ADC and six 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 the reference of a dc-to-dc converter using the DAC outputs.For more information about the ADM1062 register map, refer to the AN-698 Application Note. APPLICATIONS Central office systems Servers/routers Multivoltage system line cards DSP/FPGA supply sequencing In-circuit testing of margined supplies

The ADM1064 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 ADM1064 integrates a 12-bit ADC that can be used to accurately read back up to 12 separate voltages. The device also provides up to 10 programmable inputs for moni-toring undervoltage faults, overvoltage faults, or out-of-window faults on up to 10 supplies. In addition, 10 programmable outputs can be used as logic enables. Six of these programmable outputs can 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. ApplicationsCentral office systemsServers/routersMultivoltage system line cardsDSP/FPGA supply sequencingIn-circuit testing of margined supplies

The ADM13305 is a dual voltage supervisor designed to monitor two supplies and provide a reset signal to DSP and microprocessor-based systems.There are five models available, all of which feature a combination of internally pretrimmed undervoltage threshold options for monitoring 1.8 V, 2.5 V, 3.3 V, and 5 V supplies. There is also an adjustable input option with an undervoltage threshold voltage of 0.6 V.The ADM13305-18, ADM13305-25, and ADM13305-33 models have two internally fixed thresholds. The ADM13305-4 and ADM13305-5 offer one internally fixed threshold and one externally programmable threshold via a resistor string. See the Ordering Guide for a list of all available options.During power-up, RESETis asserted when the supply voltage exceeds 1.1 V. The device then monitors the SENSEv input pins and holds the RESET output low as long as either of the SENSEv inputs remains below the rising threshold voltage, VIT+.Once the supplies monitored at the SENSEv inputs rise above their associated thresholds, the reset signal remains low for the reset timeout period before deasserting. Subsequently, if a voltage monitored by the SENSEv pins falls below its associated falling threshold, VIT−, RESET the output asserts. The ADM13305 features both an active high RESET and an active low RESET output.As well as providing power-on reset signals, an on-chip watchdog timer can reset the microprocessor if it fails to strobe within the preset timeout period. A reset signal can also be asserted by an external push button through the manual reset input pin.The ADM13305 is available in an 8-lead, narrow body SOIC package. The device operates over the extended industrial temperature range of −40°C to +85°C.APPLICATIONS Supervising DSPs/microcontrollers Industrial and portable equipment Wireless systems Notebook/desktop computers

The ADM6711/ADM6713 are reset generator circuits suitable for use in microprocessor-based systems. They provide a reset signal on power-up, power-down, and whenever the supply voltage falls below a preset threshold. In addition, both parts have a debounced manual reset input so that a reset signal can also be initiated with an external switch or logic signal.With six different reset threshold options available ranging from 2.32 V to 4.63 V, the ADM6711/ADM6713 are suitable for monitoring 2.5 V, 3 V, 3.3 V, and 5 V supplies. A reset timeout of at least 140 ms occurs when VCC rises above the threshold. This gives the supply voltage time to stabilize before the microprocessor starts up.The ADM6711 has a push-pull output, so no additional external components are needed. The ADM6713 open-drain output requires an external pull-up resistor that can be connected to a voltage higher than VCC, if desired.The parts are highly reliable with accurate voltage references and immunity to fast, negative-going transients on VCC. Low current consumption and space-efficient, 4-lead SC70 packaging make the ADM6711/ADM6713 ideal for use in low power portable applications.APPLICATIONS Microprocessor systems Computers Controllers Intelligent instruments Automotive systems

The ADM705 / ADM706 / ADM707 / ADM708 microprocessorsupervisory circuits are suitable for monitoring 5 V powersupplies/batteries and microprocessor activity.The ADM705 / ADM706 provide power-supply monitoringcircuitry that generate a reset output during power-up, powerdown,and brownout conditions. The reset output remainsoperational with VCC as low as 1 V. Independent watchdogmonitoring circuitry is also provided. This is activated if thewatchdog input has not been toggled within 1.60 sec.In addition, there is a 1.25 V threshold detector to warn ofpower failures, to detect low battery conditions, or to monitor anadditional power supply. An active low, debounced manual resetinput (MR) is also included.The ADM705 and ADM706 are identical except for the resetthreshold monitor levels, which are 4.65 V and 4.40 V, respectively.The ADM707 and ADM708 provide a similar functionality tothe ADM705 and ADM706 and only differ in that a watchdogtimer function is not available. Instead, an active high resetoutput (RESET) is available as well as the active low reset output(RESET). The ADM707 and ADM708 are identical except forthe reset threshold monitor levels, which are 4.65 V and 4.40 V,respectively.All devices are available in narrow 8-lead PDIP and 8-lead SOICpackages.APPLICATIONS Microprocessor systems Computers Controllers Intelligent instruments Critical microprocessor supply monitoring

Designed for space-critical applications, the ADR5040 / ADR5041 / ADR5043 / ADR5044 / ADR5045 are high precisionshunt voltage references, housed in ultrasmall SC70 and SOT-23 packages. These voltage references are multipurpose, easy-to-usereferences that can be used in a vast array of applications. They feature low temperature drift, an initial accuracy of better than0.1%, and fast settling time.Available in output voltages of 2.048 V, 2.5 V, 3.0 V, 4.096 V, and 5.0 V, the advanced design of the ADR5040 / ADR5041 / ADR5043 / ADR5044 / ADR5045 eliminates the need for compensation by an external capacitor, yet the references are stable with any capacitiveload. The minimum operating current increases from 50 µA to a maximum of 15 mA. This low operating current and ease of usemake these references ideally suited for handheld, battery-powered applications. This family of references has been characterizedover the extended temperature range of −40°C to +125°C. The ADR5041W and the ADR5044W are qualified for automotiveapplications and are available in a 3-lead SOT-23 package.Applications Portable, battery-powered equipment Automotives Power supplies Data acquisition systems Instrumentation and process control Energy management

The ADP3336 is a member of the ADP333x family of precision low dropout anyCAP® voltage regulators. The ADP3336 operates with an input voltage range of +2.6 V to +12 V and delivers a continuous load current up to 500 mA. The ADP3336 stands out from the conventional LDOs with the lowest thermal resistance of any MSOP-8 package and an enhanced process that enables it to offer performance advantages beyond its competition. Its patented design requires only a 1.0 µF output capacitor for stability. This device is insensitive to output capacitor Equivalent Series Resistance (ESR), and is stable with any good quality capacitor, including ceramic (MLCC) types for space-restricted applications. The ADP3336 achieves exceptional accuracy of ±0.9% at room temperature and ±1.8% over temperature, line and load variations. The dropout voltage of the ADP3336 is only 200 mV (typical) at 500 mA. This device also includes a safety current limit, thermal overload protection and a shutdown feature. In shutdown mode, the ground current is reduced to less than 1 µA. The ADP3336 has ultralow quiescent current 80 µA (typ) in light load situations.APPLICATIONS PCMCIA Card Cellular Phones Camcorders, Cameras Networking Systems, DSL/Cable Modems Cable Set-Top Box MP3/CD Players DSP Supply

The LTC4221 is a 2-channel Hot Swap™ controller that allows a board to be safely inserted and removed from a live backplane. Using two independent high side gate drivers to control two external N-channel pass transistors, the output voltages can be ramped up with current foldback to limit the inrush current during the start-up period. No external compensation capacitors are required at the GATE pins. The two channels can be configured to ramp up and down separately or simultaneously for supply voltages ranging from 2.7V to 13.5V and 1V to 13.5V for channels 1 and 2 respectively.Each channel has two current limit comparators that provide dual level and dual speed overcurrent circuit breaker protection after the start-up period. If any current sense voltage exceeds 100mV for 1µs or 25mV for the timeout delay (set by the CFILTER at the FILTER pin), then the FAULT latch is set and both GATE pins are pulled low.The FB pins monitor the respective channel output voltages and provide the inputs for the PWRGD comparators as well as overvoltage protection.Applications Electronic Circuit Breaker Power Supply Sequencing Live Board Insertion and Removal Industrial High Side Switch/Circuit Breaker

The LTC4057 is a constant-current/constant-voltage linearcharger for single-cell lithium-ion batteries. ItsThinSOT™ package and low external component countmake the LTC4057 especially well suited for portableapplications. Furthermore, the LTC4057 is specificallydesigned to work within USB power specifications.No external sense resistor is needed and no blocking diodeis required due to the internal MOSFET architecture.Thermal feedback prevents overheating by regulating thecharge current to limit the die temperature during highpower operation or high ambient temperature conditions.The charge voltage is preset at 4.2V and the charge currentcan be programmed externally with a single resistor.When the input supply (wall adapter or USB supply) isremoved, the LTC4057 automatically enters a low currentstate, dropping the battery drain current to less than 2µA.With power applied, the LTC4057 can be put into shutdownmode, reducing the supply current to 25µA.For the standalone version (on-board charge termination)of the LTC4057, refer to the LTC4054.Applications Wireless PDAs Cellular Phones Portable Electronics