LOW COST PIR SENSOR INTERFACE ICs LSI/CSI announces the addition of three new devices to its family of PIR Sensor Interface ICs. Designated LS6511N, LS6512 and LS6513, these devices are intended for any application which requires a pulse output that will light an LED and trip open a Relay when motion is detected by a PIR Sensor. The LED and Relay coil can be returned to voltages higher than the positive rail of the chip power supply. According to Pete Visconti, LSI/CSI’s VP of Sales and Marketing, each IC contains a two-stage amplifier for direct interface with a PIR Sensor, a window comparator, digital filters, complementary pulse output drivers, a shunt regulator output for powering the PIR Sensor and a three-state Mode pin to select between Single-Pulse (single input), Dual-Pulse (two pulses within a specific time) or Concurrent-Pulse Detection (complementary inputs within a specific time). Other available features are P/N specific. They include Output Enable control (selectable with LS6513) and Undervoltage Detection circuitry (LS6511N, selectable with LS6513). The LS6511N is ideal for security systems. Its outputs can be used to generate an interrupt to a local microcontroller which could then send location information to a central station. The outputs of LS6512 can be used to remotely control motion-triggered events such as opening an automatic door or activating a camera to photograph an intruder or wildlife. Because of low current drain, the LS6512 is also ideal for remote, small area, battery-powered lighting (think closets) and responds well when batteries age because of its wide operating voltage range. For power supply systems the LS6511N includes Undervoltage Detection producing an output pulse when the power supply drops below 3.7V (to detect tampering). The LS6513 has the flexibility to be used in any application suited for either LS6511N or LS6512 because it allows the user to select Undervoltage Detection. The other LS6513 user selectable function, Output Enable, makes it easy to control whether or not to activate the Motion Sensor. Other features include: • Wide operating voltage range: 2.5V to 6.5 V (LS6512 and LS6513) • Amplifier gain and bandwidth externally controlled enabling user-tailored performance optimization • Open-Drain outputs for direct drive of a Relay coil and LED indicator. • External RC control of: Filter time Maximum separation time for detection of two pulses Output pulse width LS6511N and LS6512 are available in 14-Pin DIP and SOIC packages and LS6513 is available in 16-Pin DIP and SOICNB packages.