Holtek New Product Release - HT95R23/HT95R33 Telephone Microcontroller

June 9, 2008

The HT95R23 and HT95R33 are two new additions to Holtek’s range of telephone microcontrollers. Common features to the devices are 4K x 16 of Program Memory, 1152 bytes of Data Memory, 36 or 28 I/O lines, an 8-level stack, two 16-bit timers, an RTC Timer and four external interrupts etc. With regard to packaging the devices come in 48-pin SSOP package types. The internal Programmable Frequency Divider function can generate precise frequencies and which if used in conjunction with appropriate external audio generator components can produce attractive musical sounds or can be used to generate infrared carrier signals.

Both the HT95R23 and HT95R33 posses an internal DTMF Generator function, which can be used in various communication products, such as multi-function telephones, cordless phones, answering machines, home security products etc. With home security receiving increasing present day importance, by using microcontrollers from this device range, and together with accompanying software and hardware control, provides the means for alarm and auto dial home security systems to be easily implemented. The HT95R33 also includes a DTMF Receiver which can decode incoming DTMF signals, allowing it to be used in products which need to display incoming telephone numbers. An additional function available with this internal DTMF decode function, is to allow an external telephone to act like a remote access terminal which can be used to setup various household electrical products. This series of devices gives users a high performance/price ration device solution for use in a wide range of related telephone communication products.

Other special features within the HT95R23 and HT95R33 include a high level of integration, low cost and low power consumption. Like other devices in the Holtek microcontroller range, these two devices have high noise immunity characteristics and include a watchdog function to ensure a high level of resistance to malfunction in poor operating environments. The devices are of course fully supported by Holtek’s HT-IDE3000 hardware and software tools which include all the features one would expect of a high performance development system such as real-time hardware emulation, register and memory read/write functions, breakpoints with logical setups and trace analysis etc. All these features are provided to ensure that designers are fully equipped with the right tools to ensure their new product application code is debugged and designed as efficiently and rapidly as possible.