Overview
Features and Benefits
- Guaranteed Reset Assertion at VCC = 1V
- 1.5mA Maximum Supply Current
- Fast (35ns Max) Onboard Gating of RAM Chip Enable Signals
- SO-8 and S16 Packaging
- 4.65V Precision Voltage Monitor
- Power OK/Reset Time Delay: 50ms, 200ms or Adjustable
- Minimum External Component Count
- 1μA Maximum Standby Current
- Voltage Monitor for Power-Fail or Low Battery Warning
- Thermal Limiting
- Performance Specified Over Temperature
- Superior Upgrade for MAX690 Family
Product Details
The LTC690 family provides complete power supply monitoring and battery control functions for microprocessor reset, battery backup, CMOS RAM write protection, power failure warning and watchdog timing. A precise internal voltage reference and comparator circuit monitor the power supply line. When an out-of-tolerance condition occurs, the reset outputs are forced to active states and the chip enable output unconditionally write-protects external memory. In addition, the RESET output is guaranteed to remain logic low even with VCC as low as 1V.
The LTC690 family powers the active CMOS RAMs with a charge pumped NMOS power switch to achieve low dropout and low supply current. When primary power is lost, auxiliary power, connected to the battery input pin, powers the RAMs in standby through an efficient PMOS switch.
For an early warning of impending power failure, the LTC690 family provides an internal comparator with a user-defined threshold. An internal watchdog timer is also available, which forces the reset pins to active states when the watchdog input is not toggled prior to a preset timeout period.
Applications
- Critical μP Power Monitoring
- Intelligent Instruments
- Battery-Powered Computers and Controllers
- Automotive Systems
Product Lifecycle
Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Documentation & Resources
Tools & Simulations
LTspice
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
Models for the following parts are available in LTspice:
LTC691
Design Resources
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.View our quality and reliability program and certifications for more information.
| Part Number | Material Declaration | Reliability Data | Pin/Package Drawing | CAD Symbols, Footprints & 3D Models |
|---|---|---|---|---|
| LTC691CN#PBF | Material Declaration | Reliability Data | 16-Lead PDIP (Narrow 0.30 Inch) | |
| LTC691CSW#PBF | Material Declaration | Reliability Data | 16-Lead SOIC (Wide 0.3 Inch) | |
| LTC691CSW#TRPBF | Material Declaration | Reliability Data | 16-Lead SOIC (Wide 0.3 Inch) | |
| LTC691IN#PBF | Material Declaration | Reliability Data | 16-Lead PDIP (Narrow 0.30 Inch) | |
| LTC691ISW#PBF | Material Declaration | Reliability Data | 16-Lead SOIC (Wide 0.3 Inch) | |
| LTC691ISW#TRPBF | Material Declaration | Reliability Data | 16-Lead SOIC (Wide 0.3 Inch) | |
| Wafer Fabrication Data | R163 Reliability Data |
PCN-PDN Information
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Support & Discussions
Sample & Buy
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Buy Now Pricing
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List Pricing
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Lead Times
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