Low Noise Single-Ended to Differential Converter/ADC Driver

The LT6350 is a rail-to-rail input and output low noise single-ended to differential converter/ADC driver featuring fast settling time. It converts a high or low impedance, single-ended input signal to a low impedance, balanced, differential output suitable for driving high performance differential succesive approximation register (SAR) ADCs. The two op amp topology features very low noise op amps, that can support SNR >110dB in a 1MHz bandwidth.

The input op amp is trimmed for constant low input-referred voltage offset over the input range to prevent VOS steps from degrading distortion.

On a single 5V supply, the outputs can swing from 55mV to 4.945V. With the addition of a negative supply, the LT6350 can swing from 0V to 4.945V. Output common mode voltage is set by applying a voltage to the +IN2 pin.

The LT6350 draws 4.8mA from a 5V supply and consumes just 60μA in shutdown mode.

The LT6350 is available in a compact 3mm × 3mm, 8-pin leadless DFN package and also in an 8-pin MSOP package and operates over a –40°C to 125°C temperature range.

Applications

* 16-Bit and 18-Bit SAR ADC Drivers

* Single-Ended to Differential Conversion

* Differential Line Driver

* Rail-to-Rail Input and Outputs

* Fast Settling Time: 240ns, 0.01%, 8VP-P Output Step

* 1.9nV/√Hz Input-Referred Op Amp Noise

* High Impedance Input

* –3dB Bandwidth: 33MHz

* 2.7V to 12V Supply Operation

* No External Gain Resistors Required

* 4.8mA Supply Current

* Low Power Shutdown

* Low Distortion (HD2/HD3): –102dBc/–97dBc at 100kHz, VOUTDIFF = 4VP-P

* Low Offset Voltage: ±400μV Max

* High DC Linearity: <±1LSB, 16-Bit, 8VP-P

* Low Input Current Noise: 1.1pA/√Hz

* 3mm × 3mm 8-Pin DFN and 8-Lead MSOP Packages