MAX4208/MAX4209
Ultra-Low Offset/Drift, Precision
Instrumentation Amplifiers with REF Buffer
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Note 1: Specifications are 100% production tested at +25°C, unless otherwise noted. Limits over temperature are guaranteed by design.
Note 2: Guaranteed by design. Thermocouple and leakage effects preclude measurement of this parameter during production testing.
Devices are screened during production testing to eliminate defective units.
Note 3: IN+ and IN- are gates to CMOS transistors with typical input bias current of 1pA. CMOS leakage is so small that it is impractical to
test and guarantee in production. Max V
DIFF
is ±100mV. Devices are screened during production testing to eliminate defective
units. For the MAX4208, when there are no external resistors, the input bias current at FB and REF is 1pA (typ).
Note 4: Setting REF to ground (V
SS
) is allowed if the REF buffer is off. The unity-gain buffer is on when V
REFIN/MODE
is between 0.15V
and (V
DD
- 1.3V). In this range, V
REF
= V
REFIN/MODE
±40µV (maximum buffer input offset voltage over temperature). Setting
REFIN/MODE to V
DD
puts the part in shutdown (I
DD
= 1.4µA).
Note 5: This is the REF current needed to directly drive the end terminal of the gain-setting resistors when REFIN/MODE is connected to
V
SS
to put the buffer in high-impedance mode. The REF input current is tested at the gain of 100. At gain 10 and 1000, I
REF
=
±100µA and 3.4µA, respectively at +25°C. See the Detailed Description.
Note 6: Output swing high (V
OH
) and output swing low (V
OL
) are measured only on G = 100 and G = 1000 devices. Devices with G = 1
and G = 10 have output swing high limited by the range of V
REF
, V
CM
, and V
DIFF
(see the Output Swing section).
Note 7: Maximum range for V
DIFF
is from -100mV to +100mV.
Note 8: At G = 100V/V and G = 1000V/V, these instrumentation amplifiers are bandwidth limited and not capable of slew-rate-limited dV/dt.
ELECTRICAL CHARACTERISTICS (continued)
(V
DD
= 5V, V
SS
= 0V, V
CM
= V
REF
= V
DD
/2, V
REFIN/MODE
= V
SS
, R
L
= 100kΩ to V
DD
/2, V
DIFF
= (V
IN+
- V
IN-
) = 0V, MAX4208 set for
G = 100V/V (R1 = 1kΩ, R2 = 99kΩ), T
A
= -40°C to +125°C, unless otherwise noted.) (Note 1)
