AD8210YRZ Analog Devices Inc, AD8210YRZ Datasheet - Page 14

• Manufacturer Part Number: AD8210YRZ
• Description: IC CURRENT MONITOR 0.5% 8SOIC
• Manufacturer: Analog Devices Inc

Specifications of AD8210YRZ

• Design Resources: High Voltage, High Precision Current Sensing with Output Level Shifting Using AD8210 and AD8274 (CN0116)
• Function: Current Monitor
• Sensing Method: High/Low-Side
• Accuracy: ±0.5%
• Voltage - Input: -2 ~ 65 V
• Current - Output: 5mA
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• No. Of Amplifiers: 2
• Input Offset Voltage: 1mV
• Gain Db Max: 20dB
• Bandwidth: 500kHz
• Cmrr: 120dB
• Slew Rate: 3V/µs
• Supply Voltage Range: 4.5V To 5.5V
• Supply Current: 2mA
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

AD8210
APPLICATIONS INFORMATION
The AD8210 is ideal for high-side or low-side current sensing.
Its accuracy and performance benefits applications, such as
3-phase and H-bridge motor control, solenoid control, and
power supply current monitoring.
For solenoid control, two typical circuit configurations are used:
high-side current sense with a low-side switch, and high-side
current sense with a high-side switch.
HIGH-SIDE CURRENT SENSE WITH A LOW-SIDE
SWITCH
In this case, the PWM control switch is ground referenced. An
inductive load (solenoid) is tied to a power supply. A resistive
shunt is placed between the switch and the load (see Figure 33).
An advantage of placing the shunt on the high side is that the
entire current, including the recirculation current, can be meas-
ured because the shunt remains in the loop when the switch is
off. In addition, diagnostics can be enhanced because short circuits
to ground can be detected with the shunt on the high side.
In this circuit configuration, when the switch is closed, the
common-mode voltage moves down to the negative rail. When
the switch is opened, the voltage reversal across the inductive
load causes the common-mode voltage to be held one diode
drop above the battery by the clamp diode.
HIGH-SIDE CURRENT SENSE WITH A HIGH-SIDE
SWITCH
This configuration minimizes the possibility of unexpected
solenoid activation and excessive corrosion (see Figure 34). In
this case, both the switch and the shunt are on the high side.
When the switch is off, the battery is removed from the load,
which prevents damage from potential short circuits to ground,
while still allowing the recirculation current to be measured and
diagnostics to be preformed. Removing the power supply from
the load for the majority of the time minimizes the corrosive
effects that could be caused by the differential voltage between
the load and ground.
BATTERY
SWITCH
CLAMP
DIODE
SHUNT
Figure 33. Low-Side Switch
INDUCTIVE
LOAD
+IN
–IN
V
GND
REF
NC = NO CONNECT
AD8210
1
V
+V
REF
5V
S
0.1µF
2
OUT
NC
Rev. B | Page 14 of 16
Using a high-side switch connects the battery voltage to the
load when the switch is closed. This causes the common-mode
voltage to increase to the battery voltage. In this case, when the
switch is opened, the voltage reversal across the inductive load
causes the common-mode voltage to be held one diode drop
below ground by the clamp diode.
H-BRIDGE MOTOR CONTROL
Another typical application for the AD8210 is as part of the
control loop in H-bridge motor control. In this case, the AD8210
is placed in the middle of the H-bridge (see Figure 35) so that it
can accurately measure current in both directions by using the
shunt available at the motor. This configuration is beneficial for
measuring the recirculation current to further enhance the
control loop diagnostics.
The AD8210 measures current in both directions as the H-bridge
switches and the motor changes direction. The output of the
AD8210 is configured in an external reference bidirectional
mode (see the Modes of Operation section).
BATTERY
MOTOR
SHUNT
SWITCH
Figure 35. Motor Control Application
CLAMP
DIODE
SHUNT
Figure 34. High-Side Switch
+IN
–IN
INDUCTIVE
LOAD
+IN
–IN
V
GND
REF
AD8210
1
V
GND
REF
NC = NO CONNECT
V
NC = NO CONNECT
AD8210
+V
REF
5V
1
S
0.1µF
2
V
+V
REF
5V
OUT
NC
S
0.1µF
2
OUT
NC
CONTROLLER
2.5V
5V