Si8501-C-IM Silicon Laboratories Inc, Si8501-C-IM Datasheet - Page 9

• Manufacturer Part Number: Si8501-C-IM
• Description: Board Mount Current Sensors 5A SINGLE OUTPUT 1kV
• Manufacturer: Silicon Laboratories Inc
• Type: AC Current Sensorr
• Series: -r

Specifications of Si8501-C-IM

• Current Rating: 5 A
• Supply Voltage: 2.7 V to 5.5 V
• Frequency Range: 50 KHz to 1 MHz
• Operating Temperature: - 40 C to + 125 C
• Accuracy: 5 %
• Current - Sensing: 5A
• Sensitivity: 392mV/A
• Current - Supply: 4mA
• Sensor Type: Closed Loop
• Voltage - Supply: 2.7 V ~ 5.5 V
• Output: Configurable
• Frequency: 50kHz ~ 1MHz
• Response Time: -
• Polarization: Unidirectional
• Package / Case: 12-QFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

2. Functional Overview
The Si85xx ac current sensor family of products mimics
the functionality of traditional current transformer (CT)
circuits with burden resistor, diode, and output filter, but
offers enhanced performance and added capabilities.
These devices use inductive current sensing and on-
board signal conditioning electronics to generate a 2 V
full-scale output signal proportional to the ac current
flowing from the IIN to the IOUT terminals. As shown in
Figures 2 and 3, current flowing through the metal
package slug induces a signal in the pickup coil on the
Si85xx die. This signal is applied to the input of an
integrator that reconstructs the ac current flowing from
IIN to IOUT. Onboard circuitry provides cycle-by-cycle
integrator reset and temperature and offset voltage
compensation to achieve initial measurement accuracy
to within ±5%.
Figure 2. Si850x (Single Output) Block Diagram
IOUT
IIN
SENSOR
PICKUP
TEMP
COIL
GND2
INTEGRATOR
GND1
ADC
VDD1
RESET LOGIC
R1
AUTO CALIBRATION
R2
SIGNAL CONDITIONING
GND3
LOGIC
TRST
Si850x
Preliminary Rev. 0.21
VDD2
NC
OUT
The Si85xx is superior to other current sensing
approaches and benefits the system in a number of
ways:







Figure 3. Si851x (Ping Pong Output) Block
Small size: With its 4x4 mm footprint and 1 mm
height (QFN package option), the Si85xx is among
the smallest current sensors available.
Large output signal: The nominal 2.0 V full-scale
output swing offers superior noise immunity versus
other current sensing technologies.
Low loss: The Si85xx adds only 1.3 m (at 25 °C)
to the sensing path, making it one of the lowest-loss
current sensors available. Low 2 nH primary series
inductance is 2,000 times lower compared to a CT
and results in significantly less ringing.
High precision: All versions are available with an
initial maximum error of ±5% of reading; one of the
most accurate current sensors available.
Ping-Pong output mode (Si851x): Alternately
routes the current measurements from each side of
a full-bridge circuit to separate output pins for
comparison, which is very useful for transformer flux
balancing applications. Eliminates a second CT in a
full-bridge application.
Leading edge noise suppression: Filters out
reflected noise due to long reverse recovery time of
output rectifier. Eliminates the need for external
leading edge blanking circuit.
High common-mode voltage: The Si85xx offers a
minimum of 1,000 V
5 kV
voltage range (or isolation), making it useful over a
very wide voltage range.
IOUT
IIN
RMS
SENSOR
PICKUP
TEMP
COIL
(for SOIC package) of common-mode
INTEGRATOR
GND
ADC
R1
RESET LOGIC
R2
VDD
Diagram
RMS
R3
AUTO CALIBRATION
SIGNAL CONDITIONING
(for QFN package) or
R4
LOGIC
MODE LOGIC
TRST/FAULT
Si851x
Si85xx
MODE
OUT1
OUT2
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