FEATURES
s s DESCRIPTIO s s s s s s s s s Allows Dynamic Control of Output Frequency, Cadence, Amplitude and DC Offset Active Tracking Supply Configuration Allows Linear Generation of Ring Tone Signal No High Voltage Post-Filtering Required Capacitive Isolation Eliminates Optocouplers Low Distortion Output Meets International PTT Requirements Differential Input Signal for Noise Immunity User Adjustable Active Output Current Limit Powered Directly From High Voltage Ringer Supply—No Additional Supplies Necessary Supply Current: < 1mA 2% Signal Amplitude Reference Available in 14-Pin SO and DIP Packages The LT®1684 is a telecommunication ring tone generator. The IC takes a user-generated pulse width modulated (PWM) input and converts it to a high voltage sine wave suitable for telephone ringing applications. The LT1684 uses its own ring tone output as a reference for generating local supply rails using complementary high voltage external MOSFETs as dynamic level-shifting devices. This “ac...
Linear Technology
