MAX4208AUA+ Maxim Integrated Products, MAX4208AUA+ Datasheet - Page 15

• Manufacturer Part Number: MAX4208AUA+
• Description: IC INSTRUMENT AMP PREC 8-UMAX
• Manufacturer: Maxim Integrated Products

Specifications of MAX4208AUA+

• Amplifier Type: Instrumentation
• Number Of Circuits: 1
• Output Type: Rail-to-Rail
• Slew Rate: 0.08 V/µs
• Gain Bandwidth Product: 750kHz
• Current - Input Bias: 1pA
• Voltage - Input Offset: 3µV
• Current - Supply: 1.4mA
• Current - Output / Channel: 25mA
• Voltage - Supply, Single/dual (±): 2.85 V ~ 5.5 V, ±1.425 V ~ 2.25 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-MSOP, Micro8™, 8-uMAX, 8-uSOP,
• Number Of Channels: Single
• Common Mode Rejection Ratio (min): 106 dB
• Input Offset Voltage: 0.02 mV
• Input Bias Current (max): 0.000001 uA
• Operating Supply Voltage: 3 V, 5 V
• Supply Current: 2.3 mA
• Maximum Power Dissipation: 362 mW
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Maximum Dual Supply Voltage: +/- 2.75 V
• Minimum Dual Supply Voltage: +/- 1.425 V
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 2.85 V
• No. Of Amplifiers: 1
• Bandwidth: 750kHz
• Amplifier Output: Rail To Rail
• Cmrr: 135dB
• Supply Voltage Range: ± 1.425V To ± 2.75V
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• -3db Bandwidth: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

The ultra-low V
scale V
sive current sensing using milliohm sense resistors to
get high accuracy. Previous methods used the internal
resistance of the inductor in the step-down DC-DC con-
verter to measure the current, but the accuracy was
only 20% to 30%. Using a full-scale V
20µV max, V
Figure 5. MAX4208/MAX4209 Used as Precision Current-Sense Amplifiers for Notebook Computers with V
SENSE
Instrumentation Amplifiers with REF Buffer
of only 10mV to 20mV for minimally inva-
OS
OS
V
POWER IN R
OUT = G x 20mV = 100 x 20mV = 2V
SENSE
of the MAX4208/MAX4209 allows full-
error term is less than 0.1% and
______________________________________________________________________________________
= 10A x 0.002Ω = 20mV
SENSE
= 10A x 20mV = 200mW
1V AT 10A
V
DD
R4
R3
/2
G = 1 + R2
+V
0.002Ω
SENSE
SENSE
Ultra-Low Offset/Drift, Precision
R1
-
MAX4208
of 20mV, a
ASIC
MAX4209H
IN-
IN+
REFIN/MODE
REF
FB
MAX4209H gain error is 0.25% max at 100x, so the
total accuracy is greatly improved. The 0 to 2V output
of MAX4209H can be sent to an ADC for calculation.
The adjustable gain of MAX4208, can be set to a gain
of 250x using 1kΩ and 249kΩ resistors, to scale up a
lower 10mV V
age for wider dynamic range as needed.
IN+
IN-
REF
+3.3V
V
V
V
V
DD
SS
SS
DD
REFIN/MODE
OUT
Typical Application Circuit
SENSE
R2
FB
R1
REF
OUT
5V
ANTI-ALIASING
BUFFER OUT =
V
DD
FILTER
/2
C
voltage to a larger 2.5V output volt-
FB
ADC
SENSE
of 20mV
15