THS3217IRGVT

The THS3217 integrates the key signal chain components required when connecting to complementary current-output digital-to-analog converters (DACs). This two-stage amplifier system offers great flexibility and can be widely used in various systems to provide low-distortion, DC-coupled differential-to-single-ended signal processing. The input stage buffers the DAC resistor terminals and performs a differential-to-single-ended conversion of the signal with a fixed gain of 2V/V. The differential-to-single-ended output can be used directly externally or connected to the input of the internal output power stage (OPS) via an RLC filter or an attenuator. The wideband, current-feedback output power stage allows flexible external gain setting for all pins. The non-inverting input of the output power stage is internally connected to a 2×1 multiplexer (mux) for easy selection of the internal differential-to-single-ended stage (D2S) output or an external input. An optional on-chip mid-voltage buffer provides a wideband, low-output impedance power supply for biasing through the signal path stages during single-supply operation. This feature offers a very simple biasing method for applications operating with a supply voltage up to 15.8V. When the buffer is connected to an external input, it can implement a DC correction loop or a simple output DC offset function. A companion device, the THS3215, provides the same functionality with lower quiescent power and bandwidth. The THS3217 and THS3215 support Texas Instruments' (TI) newly launched high-speed DACs for arbitrary waveform generator (AWG) applications, such as the DAC38J82.

Applications

• DAC output amplifier
• Wideband arbitrary waveform generator (AWG) output driver
• Pre-driver to >20V_PP output amplifier (THS3091)
• Single-supply, high capacitive load driver for piezoelectric components

Key features

• Input stage: 2V/V internal gain
• Buffered differential inputs
• Single-ended low-impedance output
• Full-power bandwidth: 500MHz (2VPP)
• Output stage: externally configurable gain
• Full-power bandwidth: 500MHz (5VPP)
• Slew rate: 5000V/μs
• SPDT input switch/multiplexer
• Complete signal path: input stage + output stage
• HD2 (20MHz, 5VPP into 100Ω load): –60dBc
• HD3 (20MHz, 5VPP into 100Ω load): –75dBc
• 10VPP output into 100Ω load using ±6.5V split supplies
• 12VPP output into high-capacitive load using 15V single supply
• Internal DC reference buffer with low-impedance output
• Supply range: split supply: ±4V to ±7.9V; single supply: 8V to 15.8V