Holtek announced its new digital servo MCUs, the HT45F4840 and HT45F4842. These devices are specifically designed for use in the brushed DC motor digital servo application area and in having an internal DC motor 10-bit PWM module and a high-speed UART, they are extremely suitable for use in UART servo and PWM servo products.
Regarding the main MCU resources, these devices have 4K×16 of Flash Program Memory, 256 bytes of RAM Data Memory and a system frequency of 16MHz. For different system voltages, an internal LDO is included to provide a 3.3V or 5V voltage source. The integrated DC motor 10-bit PWM module provides complementary PWM outputs with dead time control and mistake-proofing functions. Also included is a high-speed UART interface with a speed of up to 1M bit/s. By using the In Application Programming function, users can update program memory data via the single wire half-duplex UART interface.
For higher torque servo motor applications, the HT45F4840 device can be used together with external MOSFETs with different driving capacity according to user’s requirements. This device is available in 10-pin SOP, 16-pin NSOP and 16-pin QFN (3×3) package types.
The HT45F4842 device includes an internal H-Bridge driver as well as over current and over temperature protection functions and only requires a few passive components thus greatly reducing the required PCB area and component costs. The device is available in 10-pin SOP-EP and 24-pin QFN (4×4) package types.
To complement the device series, Holtek also provides a Servo Motor Wizard where the MCU internal parameters and IAP programming can be adjusted to allow for rapid development for various types of servo motor solutions. An additional benefit of the IAP function is that it can execute the updated program procedure without removing the servo motor module. These new devices offer a much higher level of functional integration and greater flexibility over previous traditional solutions.
