HT46R064D/065D/066D
Enhanced A/D Type 8-Bit OTP MCU with LED Driver
For applications that operate within an environment where more noise is present the Enhanced Reset
Circuit shown is recommended.
Note:
²*² It is recommended that this component is added for added ESD protection
²**² It is recommended that this component is added in environments where power line noise
is significant
External RES Circuit
More information regarding external reset circuits is located in Application Note HA0075E on the
Holtek website.
RES Pin Reset
This type of reset occurs when the microcontroller is already running and the RES pin is forcefully
pulled low by external hardware such as an external switch. In this case as in the case of other reset, the
Program Counter will reset to zero and program execution initiated from this point.
Note: tRSTD is power-on delay, typical time=50ms
RES Reset Timing Chart
Low Voltage Reset - LVR
The microcontroller contains a low voltage reset circuit in order to monitor the supply voltage of the
device. The LVR function is selected via a configuration option. If the supply voltage of the device
drops to within a range of 0.9V~VLVR such as might occur when changing the battery, the LVR will
automatically reset the device internally. For a valid LVR signal, a low supply voltage, i.e., a voltage in
the range between 0.9V~VLVR must exist for a time greater than that specified by tLVR in the A.C.
characteristics. If the low supply voltage state does not exceed this value, the LVR will ignore the low
supply voltage and will not perform a reset function. The actual VLVR value can be selected via
configuration options.
Note: tRSTD is power-on delay, typical time=50ms
Low Voltage Reset Timing Chart
Rev. 1.00
36
January 12, 2011
HOLTEK [ HOLTEK SEMICONDUCTOR INC ]
