Datasheet

Data Sheet AD7294
Rev. H | Page 7 of 48
Parameter Min Typ Max Unit Test Conditions/Comments
TEMPERATURE SENSOR—INTERNAL
Operating Range −40 +105 °C
Accuracy ±2 °C Internal temperature sensor, T
A
= −30°C to +90°C
±2.5 °C Internal temperature sensor, T
A
= −40°C to +105°C
Resolution 0.25 °C LSB size
Update Rate 5 ms
TEMPERATURE SENSOR—EXTERNAL External transistor is 2N3906
Operating Range −55 +150 °C Limited by external diode
Accuracy ±2 °C T
A
= T
DIODE
= −40°C to +105°C
Resolution 0.25 °C LSB size
Low Level Output Current Source
2
8 µA
Medium Level Output Current Source
2
32 µA
High Level Output Current Source
2
128 µA
Maximum Series Resistance (R
S
) for
External Diode
2
100 Ω For < ±0.5°C additional error, C
P
= 0, see Figure 31
Maximum Parallel Capacitance (C
P
) for
External Diode
2
1 nF R
S
= 0, see Figure 30
CURRENT SENSE V
PP
= AV
DD
to 59.4 V
V
PP
Supply Range AV
DD
59.4 V
Gain 12.4375 12.5 12.5625 Gain of 12.5 gives a gain error = 0.5% maximum;
delivers ±200 mV range with +2.5 V reference
RS(+)/RS(−) Input Bias Current 25 32 µA
CMRR/PSRR
2
80 dB Inputs shorted to V
PP
Offset Error ±50 ±340 µV
Offset Drift 1 µV/°C
Amplifier Peak-To-Peak Noise
2
400 µV Referred to input
V
PP
Supply Current 0.18 0.25 mA V
PP
= 59.4 V
REFERENCE
Reference Output Voltage 2.49 2.51 V ±0.2% maximum at 25°C only
Reference Input Voltage Range 0.1 4.1 V For four uncommitted ADCs
1 AV
DD
− 2 For current sense
DC Leakage Current ±2 μA
V
REF
Output Impedance
2
25 Ω
Input Capacitance
2
20 pF
Reference Temperature Coefficient 10 25 ppm/°C
1
See the Terminology section for more details.
2
Sampled during initial release to ensure compliance, not subject to production testing.
3
V
IN+
or V
IN−
must remain within GND/V
DD
.
4
V
IN−
= 0 V for specified performance. For full input range on V
IN−
, see Figure 40.