Datasheet

0.1 F(typ)m
VDD
VDD
SDA
SCL
GPIO
Microcontrolleror
Microprocessor
withI CPort
2
Pull-UpResistors
1k to10k (typ)W W
5
10
1
2
3
4
ADDR
ALERT/RDY
GND
AIN0
AIN1
SCL
9
8
7
6
SDA
VDD
AIN3
AIN2
ADS1115
InputsSelected
fromConfiguration
Register
ADS1113
ADS1114
ADS1115
www.ti.com SBAS444B –MAY 2009–REVISED OCTOBER 2009
APPLICATION INFORMATION
The following sections give example circuits and The ADS1113/4/5 interface directly to standard mode,
suggestions for using the ADS1113/4/5 in various fast mode, and high-speed mode I
2
C controllers. Any
situations. microcontroller I
2
C peripheral, including master-only
and non-multiple-master I
2
C peripherals, can operate
with the ADS1113/4/5. The ADS1113/4/5 do not
BASIC CONNECTIONS
perform clock-stretching (that is, they never pull the
For many applications, connecting the ADS1113/4/5
clock line low), so it is not necessary to provide for
is simple. A basic connection diagram for the
this function unless other clock-stretching devices are
ADS1115 is shown in Figure 33.
on the same I
2
C bus.
The fully differential voltage input of the ADS1113/4/5
Pull-up resistors are required on both the SDA and
is ideal for connection to differential sources with
SCL lines because I
2
C bus drivers are open-drain.
moderately low source impedance, such as
The size of these resistors depends on the bus
thermocouples and thermistors. Although the
operating speed and capacitance of the bus lines.
ADS1113/4/5 can read bipolar differential signals,
Higher-value resistors consume less power, but
they cannot accept negative voltages on either input.
increase the transition times on the bus, limiting the
It may be helpful to think of the ADS1113/4/5 positive
bus speed. Lower-value resistors allow higher speed
voltage input as noninverting, and of the negative
at the expense of higher power consumption. Long
input as inverting.
bus lines have higher capacitance and require
smaller pull-up resistors to compensate. The resistors
When the ADS1113/4/5 are converting data, they
should not be too small; if they are, the bus drivers
draw current in short spikes. The 0.1μF bypass
may not be able to pull the bus lines low.
capacitor supplies the momentary bursts of extra
current needed from the supply.
Figure 33. Typical Connections of the ADS1115
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Product Folder Link(s): ADS1113 ADS1114 ADS1115