Linear Technology LTC2472, Selectable 208sps/833sps, 16-Bit Delta Sigma ADCs with 10ppm/C Max Precision Reference. (Req DC590B) Linear Tec DC1629A 데이터 시트
제품 코드
DC1629A
LTC2470/LTC2472
6
24702fb
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 compensation
pin (COMP). REFOUT cannot 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.
CS (Pin 3): Chip Select (Active LOW) Digital Input. A LOW
CS (Pin 3): Chip Select (Active LOW) Digital Input. A LOW
on this pin enables the SDO output. A HIGH on this pin
places the SDO output pin in a high impedance state and
any inputs on SDI and SCK will be ignored.
SDI (Pin 4): Serial Data Input Pin. This pin is used to pro-
SDI (Pin 4): Serial Data Input Pin. This pin is used to pro-
gram the sleep mode and the 208sps/833sps output rate.
SCK (Pin 5): Serial Clock Input. SCK synchronizes the
SCK (Pin 5): Serial Clock Input. SCK synchronizes the
serial data input/output. Once the conversion is complete,
a new data bit is produced at the SDO pin following each
SCK falling edge. Data is shifted into the SDI pin on each
rising edge of SCK.
SDO (Pin 6): Three-State Serial Data Output. SDO is used
for serial data output during the DATA INPUT/OUTPUT
state. This pin goes Hi-Z when CS is high.
GND (Pins 7, 11, Exposed Pad Pin 13 – DFN Package):
GND (Pins 7, 11, Exposed Pad Pin 13 – DFN Package):
Ground. Connect directly to the ground plane through a
low impedance connection.
REF
REF
–
(Pin 8): Negative Reference Input to the ADC. The
voltage on this pin sets the zero input to the ADC. This
pin should be tied directly to ground or the ground sense
of the input sensor.
IN
IN
+
(LTC2472), IN (LTC2470) (Pin 9): Positive input volt-
age for the LTC2472 differential device. ADC input for the
LTC2470 single-ended device.
IN
IN
–
(LTC2472), GND (LTC2470) (Pin 10): Negative input
voltage for the LTC2472 differential device. GND for the
LTC2470 single-ended device.
V
V
CC
(Pin 12): Positive Supply Voltage. Bypass to GND
with a 10μF capacitor in parallel with a low-series-induc-
tance 0.1μF capacitor located as close to the device 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
24702 G010
–120
–100
–80
–60
–40
–20
T
A
= 25°C
TEMPERATURE (°C)
–50
CONVERSION TIME (ms)
24702 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
24702 G12
1.250305
1.250310
1.250315
1.250320
1.250325
1.250330
1.250335
T
A
= 25°C