LT6238_15 Datasheet, PDF (1/26 Pages) Linear Technology – Rail-to-Rail Output 215MHz, 1.1nV/Hz Op Amp/SAR ADC Driver

Features
n _{Low Noise: 1.1nV/√Hz}
n _{Low Supply Current: 3.5mA/Amp Max}
n _{Low Offset Voltage: 350µV Max}
n _{Fast Settling Time: 570ns to 18-Bit, 2VP-P Output}
n _{Low Distortion: THD = –116.8dB at 2kHz}
n _{Wide Supply Range: 3V to 12.6V}
n _{Output Swings Rail-to-Rail}
n _{215MHz Gain-Bandwidth Product}
n _{Specified Temperature Range: –40°C to 125°C}
n _{LT6236 Shutdown to 10µA Max}
n _{LT6236 in Low Profile (1mm) ThinSOT™ Package}
n _{Dual LT6237 in 3mm × 3mm 8-Lead DFN and 8-Lead}
MSOP Packages
n _{LT6238 in 16-Lead SSOP Package}
Applications
n _{16-Bit and 18-Bit SAR ADC Drivers}
n _{Active Filters}
n _{Low Noise, Low Power Signal Processing}
LT6236/LT6237/LT6238
Rail-to-Rail Output
215MHz, 1.1nV/√Hz
Op Amp/SAR ADC Driver
Description
The LT^®6236/LT6237/LT6238 are single/dual/quad low
noise, rail-to-rail output op amps that feature 1.1nV/√Hz
input referred noise voltage density and draw only 3.5mA
of supply current per amplifier. These amplifiers combine
very low noise and supply current with a 215MHz gain
bandwidth product and a 70V/µs slew rate. Low noise, fast
settling time and low offset voltage make this amplifier
optimal to drive low noise, high speed SAR ADCs. The
LT6236 includes a shutdown feature that can be used to
reduce the supply current to less than 10µA.
This amplifier family has an output that swings within
50mV of either supply rail to maximize the signal dynamic
range in low supply applications and is specified on 3.3V,
5V and ±5V supplies.
The LT6236/LT6237/LT6238 are upgrades to the LT6230/
LT6231/LT6232, offering similar performance with reduced
wideband noise beyond 100kHz.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property
of their respective owners.
Typical Application
Differentially Driving a SAR ADC
V_S+= 6V
IN⁺ +
1/2 LT6237
–
–
1/2 LT6237
IN^– +
V_S–= –2V
LOWPASS FILTERS
38.3Ω
49.9Ω
270pF
38.3Ω
270pF
49.9Ω
IN⁺
LTC2389-18
IN^–
18-BIT
2.5Msps
623637 TA01a
LT6237 Driving LTC2389-18 f_IN = 2kHz,
–1dBFS, 32768-Point FFT
0
–10
V_OUT = 7.3V_P-P
–20
–30
HD2 = –129.5dBc
HD3 = –118.7dBc
SFDR = 117.7dB
–40
THD = –116.8dB
–50
SNR = 99.7dB
–60
SINAD = 98.9dB
–70
–80
–90
–100
–110
–120
–130
–140
–150
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2
FREQUENCY (MHz)
62367 TA01b
For more information www.linear.com/LT6236
623637fb
1