LTC6991 Datasheet | Linear Technology

Data Sheet.in Electrical Specifications Subject to Change LTC6991 Timer Blox: Resettable Low Frequency Oscillator Features n n n n n n n n n n Description The LTC®6991 is a silicon oscillator with a programmable period range of 1.024ms to 9.54 hours (29.1µHz to 977Hz), specifically intended for long duration timing events. The LTC6991 is part of the Timer Blox™ family of versatile silicon timing devices. A single resistor, RSET , programs the LTC6991’s internal master oscillator frequency. The output clock period is determined by this master oscillator and an internal frequency divider, NDIV , programmable to eight settings from 1 to 221. t OUT = NDIV - RSET - 1.024ms, NDIV = 18 , , 64,..., 221 50kΩ Period Range: 1ms to 9.5 Hours Configured with 1 to 3 Resistors <1.5% Maximum Frequency Error Output Reset Function 2.25V to 5.5V Single Supply Operation 55µA to 80µA Supply Current (2ms to 9.5hr Clock Period) 500µs Start-Up Time CMOS Output Driver Sources/Sinks 20m A - 40°C to 125°C Operating Temperature Range Available in Low Profile (1mm) SOT-23 (Thin SOT™) and 2mm × 3mm DFN Packages Applications n n n n n n “Heartbeat” Timers Watchdog Timers Intervalometers Periodic “Wake-Up” Call High Vibration, High Acceleration Environments Portable and Battery-Powered Equipment In normal operation, the LTC6991 oscillates with a 50% duty cycle. A reset function is provided to truncate the pulse (reducing the duty cycle). The reset pin can also be used to prevent the output from oscillating. The RST and OUT pins can be configured for active-low or active-high operation using a polarity function. POL BIT 0 0 1 1 RST PIN 0 1 0 1 OUTPUT STATE Oscillating 0 (reset) 1 (reset) Oscillating L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and Thin SOT and Timer Blox are trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. The LTC6991 is available in the 6-lead SOT-23 (Thin...