Datasheet ACS756xCB (Allegro) - 8

Fully Integrated, Hall-Effect-Based Linear Current Sensor IC ACS756xCB with 3 kVRMS Voltage Isolation and a Low-Resistance Current Conductor DEFINITIONS OF DYNAMIC RESPONSE CHARACTERISTICS Power-On Time (tPO)
When the supply is ramped to its operating voltage, the device requires a finite time to power its internal components before responding to an input magnetic field. Power-On Time, tPO , is defined as the time it takes for the output voltage to settle within ±10% of its steady state value under an applied magnetic field, after the power supply has reached its minimum specified operating voltage, VCC(min), as shown in the chart at right.
Rise Time (tr)
The time interval between a) when the device reaches 10% of its full scale value, and b) when it reaches 90% of its full scale value. The rise time to a step response is used to derive the bandwidth of the device, in which ƒ(–3 dB) = 0.35 / tr. Both tr and tRESPONSE
Power-On TIme (tPO)
are detrimentally affected by eddy current losses observed in the conductive IC ground plane. I (%) Primary Current
Propagation Delay (tPROP)
90 The time required for the device output to reflect a change in the primary current signal. Propagation delay is attributed to inductive loading within the linear IC package, as well as in the Transducer Output inductive loop formed by the primary conductor geometry. Propa- gation delay can be considered as a fixed time offset and may be 100 compensated. t
Increasing V
Rise Time, t
IOUT (V)
r Accuracy v O r e ∆Temp erature
Rise TIme (t
Accuracy
r)
25°C Only Average V
IOUT
I (%) Primary Current Accuracy v O r e ∆Temp erature 90 Accuracy 25°C Only
IP(min) –I +I P (A) P (A)
Half Scale
I
Transducer Output
P(max) 0 A
0 t Propagation Time, tPROP Accuracy 25°C Only
Propagation Delay (tPROP)
Accuracy v O r e ∆Temp erature
Decreasing VIOUT (V) Output Voltage versus Sampled Current Total Output Error at 0 A and at Half-Scale Current
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