New HT45R35 Addition to Holtek C/R-F Microcontroller Product Range

02/27/2008

To further expand the range of options in the Holtek Semiconductor Sensor type MCU range, a new addition, the HT45R35, has been added to the C/R-F family. The C/R-F function is implemented using the MCU internal oscillator circuit and its internal timers. When the external effective resistance or capacitance of the oscillator changes, the oscillator output frequency will also change leading to a change in the internal timer value. With the accompanying channel decoder to scan the multi-channels, the HT45R35 can then sense which channel condition has changed.

The HT45R35 contains 2K x 14 of Program Memory and 120 bytes of Data Memory and up to 16 I/O lines. Additionally, among the 12 C/R-F function lines, are 8 lines which can also be used as I/O lines as well as 2 lines which can be setup as external interrupt pins.

The device can be used in security applications such as for door and window detection, intruder detection etc. as well as being suitable for keyboard detection application in appliances such as fruit blenders, extractor fans etc. If it is required to drive external components such as LEDs, LED matrices or 7-segment displays, keypads etc. then the I/O port can be used for this purpose.

Similar to other devices in the Holtek microcontroller range the device has the benefits of high noise immunity as well as internal watchdog timer and LVR functions giving it excellent protection against malfunction in adverse environments. The HT45R35 is supplied in 8 package types, namely 16-pin DIP, 16-pin NSOP, 20-pin DIP, 20-pin SOP, 24-pin SKDIP, 24-pin SOP, 28-pin SKDIP and 28-pin SOP. Among these the 16-pin packages have 8 C/R-F channels while the 20-pin packages have 8 C/R-F channels and 4 I/O lines. The 24-pin packages have 8 C/R-F channels and 8 I/O lines while the 28-pin packages have 12 C/R-F channels and 8 I/O lines.