HT1621/HT1621G Revision # 3.20 RAM Mapping 32x4 LCD Controller for I/O MCU Modifications made on November 25, 2014 In the Application Circuits section, the Note description was modified. The Package Information section was modified. Revision # 3.10 Modifications made on November 5, 2012 In the Selection Table and other related sections, the 44-pin QFP package type was changed to a 44-pin LQFP package type. Revision # 3.00 Modifications made on April 29, 2011 The A.C. Characteristics section was modified. The Package Information section was modified. Revision # 2.90 Modifications made on November 9, 2010 In the A.C. Characteristics table, the tRSTD entry was added and Figure 4 was modified. The note below the Internal Resistor Type Bias Generator Configurations diagram was modified. Revision # 2.80 Modifications made on September 8, 2010 The Gold Bump part number has been added to the datasheet header. Revision # 2.70 Modifications made on May 18, 2010 In the Features, Pin Assignment and other related sections, a new HT1621 44-pin LQFP package type was added and the HT1621D 28-pin SKDIP package type was removed. The Package Information section was modified. Revision # 2.60 In the Pad Coordinates section was modified. Revision # 2.50 Modifications made on October 28, 2009 Modifications made on June 12, 2009 In the A.C. Characteristics section, the tOFF and tSR entries and other related Note description & Figure were added. Revision # 2.40 The Pin Assignment section, the 48-pin LQFP package was modified. Revision # 2.30 Modifications made on September 25, 2008 A Patent Notice has been added to the datasheet. Revision # 2.20 Modifications made on December 3, 2008 In the D.C. Characteristics section, the IOH1, IOH2 and IOH3 entries were modified. Revision # 2.21 Modifications made on February 23, 2009 Modifications made on July 24, 2008 At the Pin Assignment section, the caption 44 QFP-A was modified to 44 QFP-B package. Revision # 2.10 Modifications made on June 10, 2008 The D.C. Characteristics table was modified. Revision # 2.00 Modifications made on April 17, 2008 In the Pin Assignment section, the 44-pin QFP package was modified. Revision # 1.90 Modifications made on January 30, 2008 In the Features and other related sections a new 44-pin QFP package was added. The Pad Assignment section was modified. The Pad Coordinates section was modified. Revision # 1.80 The A.C. Characteristics section was modified. Revision # 1.70 Modifications made on December 6, 2007 Modifications made on June 29, 2005 HT1621 48-pin SSOP package and HT1621B 48-pin DIP package were deleted from the Features, Pin Assignment and other related sections. Revision # 1.60 At the A.C. Characteristics table, the following changes were made: o A 4kHz each for the 3V and 5V Min. values for fCLK1 were added. o A 125µ s each for the 3V and 5V, Write mode Max. values for tCLK were added. Revision # 1.50 Modifications made on November 26, 2004 Modifications made on October 13, 2004 At the D.C. Characteristics table, the 3V Min., Typ. and Max. values for RPH were changed from 40k, 80k, 150k to 60k, 120k, 200k respectively. Revision # 1.40 Modifications made on May 4, 2004 At the Absolute Maximum Ratings section, the Operating Temperature range was modified from (-25°C to 75°C) to (-40°C to 85°C). At the Functional Description section, Crystal Selection section was added. At the Application Circuits section, the Host controller diagram was modified by adding C1 and C2 capacitors which were connected to the ground. Then more text contents were added to the note, including a table for Crystal Error and Capacity Value. Revision # 1.30 Modifications made on August 6, 2003 At the Features section, HT1621B 48-pin LQFP package and HT1621G for Gold bumped chip package were added. At the Pin Assignment section, HT1621B 48-pin LQFP package was added. At the Pad Assignment section, Bump height, spacing and size were added. Package Information section was added. Product Tape and Reel Specifications section was added. Revision # 1.20 Two columns for HT1627 and HT16270 were deleted from the Selection Table. Revision # 1.10 Modifications made on January 10, 2001 This was posted on May 4, 2000 Some items and/or labels on the Application Circuits were updated.