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

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

The ADM823/ADM824/ADM825 are supervisory circuits that monitor power supply voltage levels and code execution integrity in microprocessor-based systems. In addition to providing power-on reset signals, an on-chip watchdog timer can reset the microprocessor if it fails to strobe within a preset timeout period. A reset signal can also be asserted by an external push-button, through a manual reset input. The three parts feature different combinations of watchdog input, manual reset input, and output stage configuration, as shown in Table 1.These parts are available in a choice of seven reset threshold options ranging from 2.19 V to 4.63 V. The reset and watchdog timeout periods are fixed at 140 ms (minimum) and 1.6 sec (typical), respectively.The ADM823/ADM824/ADM825 are available in 5-lead SC70 and SOT-23 packages and typically consume only 5 μA, making them suitable for use in low power, portable applications.Applications Microprocessor systems Computers Controllers Intelligent instruments Portable equipment

The ADP3309 is a member of the ADP330x family of precision low dropout anyCAP voltage regulators. It is pin-for-pin and functionally compatible with National’s LP2981, but offers performance advantages. The ADP3309 stands out from conventional LDOs with a novel architecture and an enhanced process. Its patented design requires only a 0.47 μF output capacitor for stability. This device is stable with any type of capacitor regardless of its equivalent series resistance (ESR) value, including ceramic types for space restricted applications. The ADP3309 achieves ±1.2% accuracy at room temperature and ±2.2% overall accuracy over temperature, line, and load regulations. The dropout voltage of the ADP3309 is only 120 mV (typical) at 100 mA. This device also includes a current limit and a shutdown feature. In shutdown mode, the ground current is reduced to ~1 μA. The ADP3309 operates with a wide input voltage range from 2.8 V to 12 V and delivers a load current in excess of 100 mA. The ADP3309 anyCAP LDO offers a wide range of output voltages. ApplicationsCellular telephones Notebook, palmtop computers Battery-powered systems PCMCIA regulator Bar code scanners Camcorders, cameras

The ADR360/ADR361/ADR363/ADR364/ADR365/ADR366 are precision 2.048 V, 2.500 V, 3.000 V, 4.096 V, 5.000 V, and 3.300 V band gap voltage references that offer low power and high precision in a compact TSOT package. Using proprietary temperature drift curvature correction techniques from Analog Devices, Inc., the ADR360/ADR361/ADR363/ADR364/ ADR365/ADR366 references achieve a low temperature drift of 9 ppm/°C in a TSOT package.The ADR360/ADR361/ADR363/ADR364/ADR365/ADR366 family of micropower, low dropout voltage references provide a stable output voltage from a minimum supply of 300 mV greater than the output. The advanced design of the devices eliminates the need for external capacitors, which further reduces board space and system cost. The combination of low power operation, small size, and ease of use makes the ADR360/ADR361/ADR363/ ADR364/ADR365/ADR366 precision voltage references ideally suited for battery-operated applications.See the Ordering Guide for automotive grades.Applications Battery-powered instruments Portable medical instruments Data acquisition systems Industrial process controls Automotive

Designed for space-critical applications, the ADR525 / ADR530 / ADR550 are high precision shunt voltage references, housed in ultrasmall SC70 and SOT-23-3 packages. These references feature low temperature drift of 40 ppm/°C, an initial accuracy of better than ±0.2%, and ultralow output noise of 18 μVP-P.Available in output voltages of 2.5 V, 3.0 V, and 5.0 V, the advanced design of the ADR525 / ADR530 / ADR550 eliminates the need for compensation by an external capacitor, yet the references are stable with any capacitive load. The minimum operating current increases from a mere 50 μA to a maximum of 15 mA. This low operating current and ease of use make these references ideally suited for handheld, battery-powered applications.A trim terminal is available on the ADR525 / ADR530 / ADR550 to allow adjustment of the output voltage over a ±0.5% range, without affecting the temperature coefficient of the device. This feature provides users with the flexibility to trim out small system errors.For better initial accuracy and wider temperature range, see the ADR5040 / ADR5041 / ADR5043 / ADR5044 / ADR5045 family at www.analog.com.APPLICATIONS Portable, battery-powered equipment Automotive Power supplies Data acquisition systems Instrumentation and process control Energy measurement

The ADP3300 is a member of the ADP330x family of precisionlow dropout anyCAP® voltage regulators. The ADP3300stands out from conventional LDOs with a novel architectureand an enhanced process. Its patented design requires only a0.47 µF output capacitor for stability. This device is stable withany capacitor, regardless of its ESR (Equivalent Series Resistance)value, including ceramic types (MLCC) for space restricted applications.The ADP3300 achieves exceptional accuracy of ±0.8%at room temperature and ±1.4% overall accuracy over temperature, line and load regulations. The dropout voltage of theADP3300 is only 80 mV (typical) at 50 mA.The ADP3300 operates with a wide input voltage range from3.0 V to 12 V and delivers a load current in excess of 50 mA. Itfeatures an error flag that signals when the device is about tolose regulation or when the short circuit or thermal overloadprotection is activated. Other features include shutdown andoptional noise reduction capabilities. The ADP330x anyCAP®LDO family offers a wide range of output voltages and outputcurrent levels from 50 mA to 200 mA: ADP3301 (100 mA) ADP3303 (200 mA)APPLICATIONS Cellular Telephones Notebook, Palmtop Computers Battery Powered Systems PCMCIA Regulators Bar Code Scanners Camcorders, Cameras

The LTC4257-1 provides complete signature and power interface functions for a device operating in an IEEE 802.3af Power over Ethernet (PoE) system. The LTC4257-1 simplifies Powered Device (PD) design by incorporating the 25k signature resistor, classification current source, input current limit, undervoltage lockout, thermal overload protection, signature disable and power good signalling, all in a single 8-pin package. The LTC4257-1 includes a precision, dual level current limit circuit. This allows it to charge large load capacitors and interface with legacy Power over Ethernet systems while maintaining compatibility with the current IEEE 802.3af specification. By incorporating a high voltage power MOSFET onboard, the LTC4257-1 provides the system designer with reduced cost while also saving board space.The LTC4257-1 can interface directly with a variety of ADI DC/DC converter products to provide a cost effective power solution for IP phones, wireless access points and other PDs. Analog Devices also provides network power controllers for Power Sourcing Equipment (PSE) applications.The LTC4257-1 is available in the 8-pin SO and low profile (3mm x 3mm) DFN packages.Applications IP Phone Power Management Wireless Access Points Telecom Power Control

The LTC2921 and LTC2922 monitor up to five supplies and force them to track on power-up in multiple supply systems. Using external N-channel pass transistors, the supplies can be ramped up at an adjustable rate. Automatic remote sense switching allows the DC/DC converters to compensate for series voltage drops in the wiring. An incorrect level on one or more of the supplies triggers disconnect of all supplies. Tight 1% accuracy and glitch immunity on the low 0.5V monitoring level ensure no false error disconnects.The LTC2921 and LTC2922 each feature an adjustable electronic circuit breaker to protect the VCC supply against short circuits. Capacitance at the TIMER pin programs the delays in the monitoring sequence.The LTC2921 includes three remote sense switches in a 16-pin narrow SSOP package, while the LTC2922 includes five remote sense switches in a 20-pin TSSOP package. Both parts are available for VCC supply voltages of 5V, 3.3V, and 2.5V.Applications Desktop Computers Plug-In Cards Telecom Infrastructure Supply Sequencing Instruments