semiconductor solutions
LDS6005
PureTouch™ Capacitance Touch IC
The LDS6005 PureTouch™ controller empowers system designers to create streamlined, attractive,
and reliable product designs, enabling the replacement of mechanical controls with capacitive touch
buttons, sliders, and scroll wheels.
Description
The LDS6005 is a programmable capacitance-to-digital converter (CDC) designed for use with capacitive
sensor arrays implementing touch-based input controls including sliders, scroll wheels, and buttons.
Featuring 10 sensor inputs, the LDS6005 provides the flexibility to implement multiple touch inputs using
a single controller.
The capacitive sensor inputs are directed through an integrated switch matrix to a 500 kHz sigma-delta
CDC which senses changes in the external sensor array. When a sufficiently large change in capacitance
occurs, a sensor activation is registered and the host processor is notified.
On-chip calibration logic continuously monitors the environment and automatically adjusts on-and-off
threshold levels to prevent false sensor activation. The LDS6005 is offered with both SPI-compatible
and I2C-compatible interfaces (active interface selected by I/F select pin) and features a general-purpose
input/output (GPIO) and interrupt output for additional communication with the host processor.
VDD1
RESETB
TEST
VDDIO
I/F SEL
SHIELD
C1
C0
C2
C3
C9
VSS1
Switch
Matrix
Serial Interface and
Control Logic Interrupt and GPIO Logic
500 kHz
Excitation
Source
Calibration
RAM
Control and
Data Registers
®
LDS6005
Power-On
Reset Logic
Calibration
Engine
Sigma-Delta
CDC
INTBGPIOCSB/
A0
SCLK/
SCL
SDI/
A1
SD0/
SDA
Figure 1. LDS6005 block diagram
1
IDT® LDS6005 PURETOUCH™ CAPACITANCE TOUCH IC
LDS6005 Features
Versatile, accurate capacitance-
to-digital converter (CDC)
• 500kHzsigma-deltaCDC
• 10capacitancesensorinputchannels
• 2msupdaterateperactivesensor
Integrated, automatic
calibration algorithms
• Environmentalcompensation
• On-chipRAMtostorecalibrationdata
Integrated touch preference modes
• Strongestsingletouch
• Strongesttwotouches
• Unrestricted(all)touches
Ultra-low touch sensor
power consumption*
• Operatingmode(typical):
<150 uW (VDD1=1.8V)
• Shutdownmode(typical):
<1 uW (VDD1=1.8V)
Flexible interface options
• SPI-compatibleserialI/F
• I2C-compatible serial I/F
• SeparateVDDIO level for serial interface
• GPIOandInterruptOutput
* Excludes I/F and voltage dependent VDDIO current