2.40

HT49R50A-1/HT49C50-1/HT49C50L
Revision # 2.40

Modifications made on July 30, 2012
In the Oscillator Configuration section, the Crystal Specifications table was added.
Revision # 2.30

LCD Type 8-Bit MCU
Modifications made on May 3, 2011
In the Features section and other related sections, the 100-pin QFP package was
changed to 100-pin LQFP.
Revision # 2.20
Modifications made on December 16, 2009

In the Features and other related sections, the 64LQFP new package type was added.

In the Absolute Maximum Ratings section, the IOL, IOH Total and Total Power
Dissipation were added.

The Instruction Set section was modified.

The Instruction Definition section was modified.

The Package Information section was modified.

The Product Tape and Reel Specifications section was modified.
Revision # 2.10

Modifications made on April 24, 2006
In the oscillator configuration and application circuit section the value of the external
oscillator resistor range was changed.
Revision # 2.00
Modifications made on November 29, 2005

The D.C. Characteristics table was modified.

At the A.C. Characteristics table, the tLVR entries was added.

The registers status in the table, the PB entries was added.

The TMR0C & TMR1C Register table, the T0E/T1E function were modified.
Revision # 1.90
Modifications made on June 10, 2005

Technical Document section was added.

Pad Assignment section was deleted.
Revision # 1.80

Modifications made on September 21, 2004
At the D.C. Characteristics table, the IDD3 Parameter, as well as Typ. and Max.
Conditions were modified.

At the table below the Application Circuits section, the entries of the column for
Crystal or Resonator were modified. A brief functional description for R1 was added at
the bottom portion of the table.
Revision # 1.70
Modifications made on May 3, 2004

The Product Title was modified from 8-Bit LCD Type MCU to LCD Type 8-Bit MCU.

At the Block Diagram section, the TMR0, TMR0C, TMR1 and TMR1C portion of the
diagram were modified.

At the Pin Description table, the OSC1 to OSC4 entries for the I/O column were
modified.

At the D.C. Characteristics table, the Min. value for the RPH 3V was changed from
40k to 20k and the Max. value from 80k to 100k.

At the A.C. Characteristics table, the 1.2V~2.2V Conditions for fSYS1, fSYS2 and fTIMER
were specified for HT49C50L.

At the Timer/Event Counter section, some of the text contents were modified,
including the Timer/Event Counter 0 and Timer/Event Counter 1 diagrams. The
Labels for the TMR0C and TMR1C Register tables were also modified.
Revision # 1.60

Modifications made on December 16, 2003
At the Instruction Set Summary and Instruction Definition sections, the missing
TABRDL [m] instructions were added back.
Revision # 1.50

Modifications made on August 27, 2003
The Application Circuits diagram was modified and the RC system oscillator range
was changed from 24k<ROSC<1M to 30k<ROSC<750k.
Revision # 1.40
Modifications made on August 18, 2003

The PD flag label was changed to PDF flag.

The Application Circuits were modified.
o
The recommended RESET circuitry was modified.
For reasons of stability and noise immunity, the 2-resistor/2-capacitor or
2-resistor/1-capacitor recommended circuits are an improvement over the
1-resistor/1-capacitor circuit. The choice of which circuit is used depends
upon the user application. For example, for battery powered applications the
single resistor and single capacitor circuit may be adequate whereas for
applications such as home appliances, industrial control applications or for
circuits which are close to electrical noise sources, the 2-resistor/2-capacitor
circuit may be the better choice.
o
The Crystal OSC application circuitry was also modified
The recommended additional resistor has been added to ensure that the
oscillator will cease to function when the supply voltage falls below 2.2V to
prevent microcontroller malfunctions. This is because of instabilities in the
oscillator at supply voltages of less than 2.2V.
o
The RC system oscillator range was changed from 24k<ROSC<1M to
30k<ROSC<750k.

The Instruction Definition section was modified, with the first two columns deleted.
Revision # 1.30
Modifications made on July 24, 2003

The General Description was modified.

The Pad Description table was modified.

The D.C. Characteristics table was modified, particularly IDD4 and ISTB2.

The register status table was modified, particularly TMR0, TMR1 and PC.

The Reset circuit was modified.

The RES pin in the Application Circuits diagram for HT49R50A-1/HT49C50-1 were
modified.
Revision # 1.20

Modifications made on January 13, 2003
At the Features section and other related sections, the Operating voltage was
modified.

Pad Assignment for HT49R50A-1 was added.

At the Absolute Maximum Ratings section, the values for the Supply Voltage range
were modified.

The D.C. Characteristics table was modified.

The A.C. Characteristics table was modified.

The LCD Driver Output section was modified.
Revision # 1.10

Modifications made on October 21, 2002
HT49C50L was added to the HT49R50A-1/HT49C50-1 series.