DS21349Q

DS21349Q application field and working principle

The DS21349 Quad Timer is part of the innovative DS213 family of devices from Dallas Semiconductor. It is used in the interface and Telecom market for providing a true four-channel time synchronous timing solution.

The four channels of the DS21349 can be configured individually as pulse or pulse width modulated (PWM) outputs, and as either true TTL logic outputs or open-collector logic output. This features a wide range of applications, including control of relays, switching times, ramp-up/down fields, and other similar requirements.

The major benefit of the DS21349 is the ability to integrate a true four-channel lead-lag timing solution in a single device. This feature makes the device particularly useful in applications where the timing of multiple events may need to be synchronized, such as when coordinating the activities of separate electronic systems.

Technical Specifications

The DS21349 includes four independent channels. Each channel includes an 8-bit programmable counter and a 4-bit programmable prescaler. The prescaler uses an internal clock source and provides an adjustable frequency divider.

The DS21349 also has a programmable polarity register, which can be used to select the active polarity of the output pins. This allows the output pins to be configured as either active-high or active-low logic levels.

The device features a very low standby power consumption and an ultra-light weight package, making it ideal for battery-powered and portable applications. Other features of the DS21349 include a fully integrated real time clock and an on-chip temperature compensation module.

How it works?

The DS21349 uses a clock source to count an internally generated time period. Once this time period has elapsed, the source clock is disabled and the device begins counting an externally applied control signal. Depending on the configuration of the control signal and the polarity register, the device will either count up or down.

The output of the count sequence will determine the activation of the four independent outputs of the device. Depending on the chosen configuration, the outputs may be enabled at any time during the count sequence or they may remain inactive until the end of the count sequence. This means that the outputs can be used to activate events at any arbitrary instant during the count sequence.

Applications

The DS21349 is designed specifically for use in the interface and Telecom market, offering a true four-channel timing solution that is infinitely scalable. The device is ideal for applications such as control of relay switching times, ramp-up/down fields, and other similar duties.

The device can also be used in the management of time-critical data, such as for the synchronization of remote sensing data between multiple sites. This makes the device perfect for use with GPS-based timekeeping systems and for synchronizing operations between different portions of a system.