BU1851GUW Datasheet, PDF (1/13 Pages) Rohm – GPIO ICs Series Key Encoder IC

GPIO ICs Series
Key Encoder IC
BU1851GUW
No.09098EAT03
●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 5A Stand-by Current
3) Built-in Power On Reset
4) Ghost key rejection
●Absolute maximum ratings
(Ta=25℃)
Item
Symbol
Value
Unit
Supply Voltage^*1
VDD
-0.3 ~ +4.5
V
Input voltage
VI
-0.3 ~ VDD +0.3^*1
V
Storage temperature range Tstg
Package power
PD
-55 ~ +125
℃
272^*2
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 _{Package dissipation will be reduced each 2.72mW/} o_{C when the ambient temperature increases beyond 25} o_C.
comment
●Operating Conditions
Item
Symbol
Supply voltage range（VDD） VDD
Input voltage range
V_IN
Operating temperature range Topr
External clock
Fclk
External resistor
Rxi
Min
2.20
-0.2
-30
0.8
118.8
Limit
Typ
3.30
-
25
1.0
120
Max
3.60
VDD+0.2
+85
1.2
121.2
Unit
V
V
℃
MHz
kΩ
Condition
CLKSEL=VDD
To Xi pin, when CLKSEL=VSS
www.rohm.com
© 2009 ROHM Co., Ltd. All rights reserved.
1/12
2009.09 - Rev.A