MK712_10 Datasheet, PDF (1/21 Pages) Integrated Device Technology – TOUCH SCREEN CONTROLLER

TOUCH SCREEN CONTROLLER
DATASHEET
MK712
Description
The MK712 Touch Screen Controller IC provides all the
screen drive, A to D converter and control circuits to easily
interface to 4-wire analog resistive touch screens.
The IC continually monitors the screen waiting for a touch.
In this mode, the supply current is typically 0.5µA. When
the screen is touched, the IC performs analog to digital
conversions to determine the location of the touch, stores
the X and Y locations in the registers, and issues an
interrupt. This process is repeated up to 197 times per
second until no further screen touches are detected, at
which time the low current mode is resumed.
Block Diagram
Features
• Packaged in 28-pin SSOP (150 mil) or 28-pin SOIC (300
mil)
• Industrial (-30°C to +70°C) and commercial (0 to +70°C)
and automotive (-35°C to +85°C) temperature ranges
• Pb (lead) free
• Fully integrated, lowest power solution
• Low standby current of 0.5µA (typical) at 5.0 V
• Active current while converting less than 10 mA
• Resolves 350 dots/inch on 10.5” display
• Maximum speed of 197 points/second
• Ratio metric conversion may eliminate screen calibration
• Automatically wakes up and goes back to standby
• 3.3 V or 5 V supply
• 12 bit A/D converter
• Simplifies the writing of software for touch screens
• Extended temperature range available
• Capacitors are the only external components required
• Touch screen is directly driven - no external transistors
are required
• Programmable conversion rate
• A to D Converter is monotonic
• Parallel interface
Pin Assignment
NC
1
INT
2
TOUCH
3
VDD
4
VDD
5
XH
6
XL
7
YH
8
YL
9
GND
10
GND
11
WR
12
RD
13
CS
14
28
D0
27
D1
26
D2
25
D3
24
D4
23
D5
22
VDD
21
GND
20
D6
19
D7
18
CLKIN
17
A0
16
A1
15
A2
IDT™ TOUCH SCREEN CONTROLLER
1
MK712
REV N 051310