IS31IO7326 Datasheet, PDF (1/14 Pages) Integrated Silicon Solution, Inc – DEBOUNCED 8×8 KEY-SCAN CONTROLLER

IS31IO7326
DEBOUNCED 8×8 KEY-SCAN CONTROLLER
January 2012
GENERAL DESCRIPTION
The IS31IO7326 is a 64 key, key-scan controller. It
offloads the burden of keyboard scanning from the host
processor. The IS31IO7326 supports keypad matrix of
up to 8×8. Key press and release events are encoded
into a byte format and loaded into a key event register
for retrieval by the host processor.
The IS31IO7326 integrates a debounce function which
rejects false or transient key switch activities. The
_______
interrupt output (INT) is used to signify if there are any
keypad activities.
To minimize power, the IS31IO7326 automatically
enters a low power standby mode when there is no
keypad, I/O, or host activity.
The IS31IO7326 is available in a Pb-free 4mm × 4mm
QFN-24 package.
FEATURES
 2.4V to 5.5V operation
 400kHz I²C serial interface
 Available for multi-key press detect
 Low 0.3μA (typ.) standby current
 Operate in -40°C to +125°C
 Pb-free 4mm × 4mm QFN-24 package
APPLICATIONS
 Keypad of QWERTY type phones
 PDAs, games, and other handheld applications
TYPICAL APPLICATION CIRCUIT
VBattery
100k
Micro
Controller
VBattery
21
1
PP0
VCC
2
PP1
1F
0.1 F
3
PP2
4
PP3
V_DD
14
PP4
15
4.7k 4.7k 4.7k
PP5
16
19
PP6
SCL
17
20
PP7
22 ^{SDA IS31IO7326}
5
INT
OD0
23
6
RST
OD1
7
100k
OD2
8
OD3
10
18
OD4
AD0
11
24
OD5
AD1
12
9
OD6
GND
13
OD7
Figure 1 Typical Application Circuit
Integrated Silicon Solution, Inc. – www.issi.com
1
Rev.A, 12/19/2011