Техническая Спецификация для Linear Technology LTC2471 - Selectable 208sps/833sps, 16-Bit I2C Delta Sigma ADCs with 10ppm/C Max Precision Reference (Req DC590B) Linear DC1718A
Модели
DC1718A
LTC2471/LTC2473
6
24713fb
For more information
pin FuncTions
REFOUT (Pin 1): Reference Output Pin. Nominally 1.25V,
this voltage sets the full-scale input range of the ADC. For
noise and reference stability connect to a 0.1µF capacitor
tied to GND. This capacitor value must be less than or
equal to the capacitor tied to the reference compensa-
tion pin (COMP). REFOUT must not be overdriven by an
external reference.
COMP (Pin 2): Internal Reference Compensation Pin. For
COMP (Pin 2): Internal Reference Compensation Pin. For
low noise and reference stability, tie a 0.1μF capacitor to
GND.
A0 (Pin 3): Chip Address Control Pin. The A0 pin can be
A0 (Pin 3): Chip Address Control Pin. The A0 pin can be
tied to GND or V
CC
. If A0 is tied to GND, the LTC2471/
LTC2473 I
2
C address is 0010100. If A0 is tied to V
CC
, the
LTC2471/LTC2473 I
2
C address is 1010100.
GND (Pins 4, 7, 11, (Exposed Pad Pin 13 – DFN Package
Only)): Ground. Connect exposed pad directly to the ground
plane through a low impedance connection.
SCL (Pin 5): Serial Clock Input of the I
SCL (Pin 5): Serial Clock Input of the I
2
C Interface. The
LTC2471/LTC2473 can only act as an I
2
C slave and the SCL
pin only accepts an external serial clock. Data is shifted
into the SDA pin on the rising edges of SCL and output
through the SDA pin on the falling edges of SCL.
SDA (Pin 6): Bidirectional Serial Data Line of the I
2
C Inter-
face. The conversion result is output through the SDA pin.
The pin is high impedance unless the LTC2471/LTC2473
is in the data output mode. While the LTC2471/LTC2473 is
in the data output mode, SDA is an open drain pull down
(which requires an external 1.7k pull-up resistor to V
CC
).
REF
–
(Pin 8): Negative Reference Input to the ADC. The
voltage on this pin sets the zero input to the ADC. This
pin should tie directly to ground or the ground sense of
the input sensor.
IN
IN
+
(LTC2473), IN (LTC2471) (Pin 9): Positive input volt-
age for the LTC2473 differential device. ADC input for the
LTC2471 single-ended device.
IN
IN
–
(LTC2473), GND (LTC2471) (Pin 10): Negative input
voltage for the LTC2473 differential device. GND for the
LTC2471 single-ended device.
V
V
CC
(Pin 12): Positive Supply Voltage. Bypass to GND with
a 10μF capacitor in parallel with a low-series-inductance
0.1μF capacitor located as close to pin 12 as possible.
Typical perForMance characTerisTics
(T
A
= 25°C, unless otherwise noted)
Power Supply Rejection
vs Frequency Applied to V
CC
Conversion Time vs Temperature
10
100
1k
1
100k 1M
10k
10M
FREQUENCY AT V
CC
(Hz)
REJECTION (dB)
0
24713 G010
–120
–100
–80
–60
–40
–20
T
A
= 25°C
TEMPERATURE (°C)
–50
CONVERSION TIME (ms)
24713 G11
4.4
4.0
4.1
4.2
4.3
3.9
3.8
–25
25
50
75
0
100
V
CC
= 2.7V
V
CC
= 4.1V
V
CC
= 5.5V
V
REF
vs V
CC
2.0
3.5
2.5
4.0
3.0
5.0 5.5
4.5
6.0
V
CC
(V)
V
REF
(V)
1.250345
1.250340
24713 G12
1.250305
1.250310
1.250315
1.250320
1.250325
1.250330
1.250335
T
A
= 25°C