MAX11156ETC+ Maxim Integrated, MAX11156ETC+ Datasheet - Page 14

• Manufacturer Part Number: MAX11156ETC+
• Description: Analog to Digital Converters - ADC 18Bit 500ksps 5V SAR ADC w/Internal Ref
• Manufacturer: Maxim Integrated

Specifications of MAX11156ETC+

• Rohs: yes
• Number Of Channels: 1
• Architecture: SAR
• Conversion Rate: 500 KSPs
• Resolution: 18 bit
• Input Type: Pseudo-Differential
• Snr: 94.6 dB
• Interface Type: SPI
• Operating Supply Voltage: 2.3 V to 5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: TDFN-12
• Maximum Power Dissipation: 38.5 W
• Minimum Operating Temperature: - 40 C
• Number Of Converters: 1

MAX11156
3) THD performance: The input buffer amplifier used
Table 2
compatible with the MAX11156. The MAX9632 has suf-
ficient bandwidth, low enough noise and distortion to sup-
port the full performance of the MAX11156. The MAX9633
is a dual amp and can support buffering for true pseudo-
differential sampling.
Transfer Function
The ideal transfer characteristic for the MAX11156 is
shown in
on the transfer function are given in
Table 2. List of Recommended ADC Driver Op Amps for MAX11156
Table 3. Transfer Function Example
www.maximintegrated.com
MAX9632
MAX9633
AMPLIFIER
is preferable to use an amplifier that will produce an
output noise spectral density of less than 6nV/√Hz, to
ensure the overall SNR is not degraded significantly.
It is recommended to insert an external RC filter at
the MAX11156 AIN+ input to attenuate out-of-band
input noise and preserve the ADC's SNR. The effec-
tive RMS noise at the MAX11156 AIN+ input is 65FV,
thus additional noise from a buffer circuit should be
significantly lower in order to achieve the maximum
SNR performance.
should have a comparable THD performance with that
of the MAX11156 to ensure the THD of the digitized
signal is not degraded.
summarizes the operational amplifiers that are
Figure
CODE TRANSITION
Midscale + 0.5 LSB
Midscale - 0.5 LSB
+FS - 1.5 LSB
-FS + 0.5 LSB
Midscale
INPUT-NOISE
3. The precise location of various points
DENSITY
(nV/√Hz)
1
3
SMALL-SIGNAL
BANDWIDTH
Table
(MHz)
55
27
3.
BIPOLAR INPUT (V)
SLEW RATE
(V/µs)
+4.999943
+0.000019
-0.000019
-4.999981
30
18
0
Figure 3. Bipolar Transfer Function
3FFFE
3FFFF
1FFFF
1FFFE
00001
20001
20000
00000
THD
(dB)
-128
-128
-FS
with Internal Reference in TDFN
18-Bit, 500ksps, ±5V SAR ADC
LSB =
+FS =
-FS =
-FS + 0.5 × LSB
(mA)
I
3.9
3.5
CC
+FS - (-FS)
5 x V
-5 x V
262144
4.096
4.096
REF
REF
INPUT VOLTAGE (LSB)
DIGITAL OUTPUT CODE (HEX)
Single amp, low noise, low THD
Dual amp, low noise, low THD
TRANSITION
0
3FFFE - 3FFFF
1FFFF - 20000
20000 - 20001
00000 - 00001
+FS - 1.5 × LSB
COMMENTS
20000
Maxim Integrated │ 14
+FS - 1LSB
+FS