Datasheet

Data Sheet AD7949
Rev. D | Page 5 of 32
Parameter Conditions/Comments Min Typ Max Unit
INTERNAL REFERENCE
REF Output Voltage 2.5 V, @ 25°C 2.490 2.500 2.510 V
4.096 V, @ 25°C 4.086 4.096 4.106 V
REFIN Output Voltage
7
2.5 V, @ 25°C 1.2 V
4.096 V, @ 25°C
2.3
V
REF Output Current ±300 µA
Temperature Drift ±10 ppm/°C
Line Regulation VDD = 5 V ± 5% ±15 ppm/V
Long-Term Drift 1000 hours 50 ppm
Turn-On Settling Time CREF = 10 µF 5 ms
EXTERNAL REFERENCE
Voltage Range REF input 0.5 VDD + 0.3 V
REFIN input (buffered) 0.5 VDD − 0.5 V
Current Drain
250 kSPS, REF = 5 V
50
µA
TEMPERATURE SENSOR
Output Voltage
8
@ 25°C
283
mV
Temperature Sensitivity 1 mV/°C
DIGITAL INPUTS
Logic Levels
V
IL
−0.3 +0.3 × VIO V
V
IH
0.7 × VIO VIO + 0.3 V
I
IL
−1 +1 µA
I
IH
−1 +1 µA
DIGITAL OUTPUTS
Data Format
9
Pipeline Delay
10
V
OL
I
SINK
= +500 µA 0.4 V
V
OH
I
SOURCE
= −500 µA VIO − 0.3 V
POWER SUPPLIES
VDD Specified performance 2.3 5.5 V
VIO Specified performance 2.3 VDD + 0.3 V
Operating range 1.8 VDD + 0.3 V
Standby Current
11, 12
VDD and VIO = 5 V, @ 25°C 50 nA
Power Dissipation VDD = 2.5 V, 100 SPS throughput 1.5 µW
VDD = 2.5 V, 100 kSPS throughput 1.45 2.0 mW
VDD = 2.5 V, 200 kSPS throughput
2.9
4.0
mW
VDD = 5 V, 250 kSPS throughput 10.8 12.5 mW
VDD = 5 V, 250 kSPS throughput with internal
reference
13.5 15.5 mW
Energy per Conversion 50 nJ
TEMPERATURE RANGE
13
Specified Performance T
MIN
to T
MAX
−40 +85 °C
1
See the Analog Inputs section.
2
The bandwidth is set in the configuration register.
3
LSB means least significant bit. With the 5 V input range, one LSB = 305 µV.
4
See the Terminology section. These specifications include full temperature range variation but not the error contribution from the external reference.
5
With VDD = 5 V, unless otherwise noted.
6
All specifications expressed in decibels are referred to a full-scale input FSR and tested with an input signal at 0.5 dB below full scale, unless otherwise specified.
7
This is the output from the internal band gap.
8
The output voltage is internal and present on a dedicated multiplexer input.
9
Unipolar mode: serial 14-bit straight binary.
Bipolar mode: serial 14-bit twos complement.
10
Conversion results available immediately after completed conversion.
11
With all digital inputs forced to VIO or GND as required.
12
During acquisition phase.
13
Contact an Analog Devices, Inc., sales representative for the extended temperature range.