MAX4238 Maxim, MAX4238 Datasheet - Page 8

• Manufacturer Part Number: MAX4238
• Description: The MAX4238/MAX4239 are low-noise, low-drift, ultra-high precision amplifiers that offer near-zero DC offset and drift through the use of autocorrelating zeroing techniques
• Manufacturer: Maxim

Autozeroing amplifiers typically require a substantial
amount of time to recover from an output overload. This
is due to the time it takes for the null amplifier to correct
the main amplifier to a valid output. The MAX4238/
MAX4239 require only 3.3ms to recover from an output
overload (see Electrical Characteristics and Typical
Operating Characteristics ).
The MAX4238/MAX4239 feature a low-power (0.1µA)
shutdown mode. When SHDN is pulled low, the clock
stops and the device output enters a high-impedance
state. Connect SHDN to V
The MAX4238 is a unity-gain stable amplifier with a gain-
bandwidth product (GBWP) of 1MHz. The MAX4239 is
decompensated for a GBWP of 6.5MHz and is stable with
a gain of 10V/V. Unlike conventional operational ampli-
fiers, the MAX4238/MAX4239 have a maximum gain
specification. To maintain stability, set the gain of the
MAX4238 between A
gain of the MAX4239 between A
The low offset, fast settling time, and 1/f noise cancella-
tion of the MAX4238/MAX4239 make these devices
ideal for ADC buffers. The MAX4238/MAX4239 are well
suited for low-speed, high-accuracy applications such
as strain gauges (see Typical Application Circuit ).
When using the MAX4238/MAX4239 as an ADC buffer,
the temperature drift should be taken into account when
determining the maximum input signal. With a typical off-
set drift of 10nV/°C, the drift over a 10°C range is 100nV.
Setting this equal to 1/2LSB in a 16-bit system yields a
full-scale range of 13mV. With a single 2.7V supply, an
acceptable closed-loop gain is A
sufficient gain while maintaining headroom.
Ultra-Low Offset/Drift, Low-Noise,
Precision SOT23 Amplifiers
8
_______________________________________________________________________________________
Applications Information
Minimum and Maximum Gain
V
Output Overload Recovery
= 1000V/V to 1V/V, and set the
CC
ADC Buffer Amplifier
for normal operation.
V
Error Budget Example
= 6700V/V and 10V/V.
V
= 200. This provides
Configurations
Shutdown
For the latest package outline information and land patterns
(footprints), go to www.maxim-ic.com/packages. Note that a
“+”, “#”, or “-” in the package code indicates RoHS status only.
Package drawings may show a different suffix character, but
the drawing pertains to the package regardless of RoHS status.
PROCESS: BiCMOS
6 SOT23
8 SO
6 TDFN
PACKAGE
SHDN
GND
IN-
IN+
TYPE
1
2
4
3
TOP VIEW
*CONNECT EP TO GND.
MAX4238/
MAX4239
SO
PACKAGE
U6F-6
S8-4
T633+2
CODE
+
(3mm x 3mm x 0.8mm)
Package Information
7
6
5
EP*
8
6
1
N.C.
V
OUT
N.C.
Pin Configurations
CC
MAX4238/
MAX4239
TDFN
OUTLINE NO.
Chip Information
5
2
GND
OUT
21-0058
21-0041
21-0137
IN+
4
3
1
2
3
MAX4238/
MAX4239
SOT23
PATTERN NO.
90-0175
90-0096
90-0058
LAND
6
5
4
V
SHDN
IN-
CC