BU1851GUW-E2 ROHM

GPIO ICs Series Key Encoder IC No.09098EAT03 BU1851GUW Description Key Encoder IC can monitor up to 8x8 matrix (64 keys), which means to be adaptable to Qwerty keyboard. We adopt the architecture that the information of the only key which status is changed, like push or release, is encoded into the 8 bits data. This can greatly reduce the CPU load which tends to become heavier as the number of keys increase. (Previously, all key s status is stored in the registers.) Furthermore, auto sleep function contribute to low power consumption, when no keys are pressed. It is also equipped with the various functions such as ghost key rejection, N-key Rollover, Built-in power on reset and oscillator. Features 1) Monitor up to 64-matrix keys 2) Under 5A Stand-by Current 3) Built-in Power On Reset 4) Ghost key rejection Absolute maximum ratings (Ta=25) Item Symbol Value Unit comment *1 Supply Voltage VDD -0.3 ~ +4.5 V *1 Input voltage VI -0.3 ~ VDD +0.3 V Storage temperature range Tstg -55 ~ +125 *2 Package power PD 272 mW This IC is not designed to be X-ray proof. *1 It is prohibited to exceed the absolute maximum ratings even including +0.3 V. *2 o o Package dissipation will be reduced each 2.72mW/ C when the ambient temperature increases beyond 25 C. Operating Conditions Limit Item Symbol Unit Condition Min Typ Max Supply voltage rangeVDD VDD 2.20 3.30 3.60 V Input voltage range V -0.2 - VDD+0.2 V IN Operating temperature range Topr -30 25 +85 External clock Fclk 0.8 1.0 1.2 MHz CLKSEL=VDD External resistor Rxi 118.8 120 121.2 k To Xi pin, when CLKSEL=VSS www.rohm.com 2009.09 - Rev.A 1/12 2009 ROHM Co., Ltd. All rights reserved. Not Recommended for New DesignsTechnical Note BU1851GUW Package Specification U1851 Lot No. Fig.1 Package SpecificationVBGA035W040 www.rohm.com 2009.09 - Rev.A 2/12 2009 ROHM Co., Ltd. All rights reserved. Not Recommended for New Designs