April 13, 2012 – Linear Technology Korea (CEO Hong Sa-kwak) announced the launch of an industry-leading 18-bit SAR ADC (Analog-to-Digital Converter) with zero cycle latency. The LTC2389-18 delivers outstanding performance including 99.8dB SNR and -116dB THD at maximum sample rates of 2.5Msps. Operating from a single 5V supply voltage, the LTC2389-18 supports three pin-selectable analog input ranges, enabling easy interfacing to multiple signal chains with a single device. To achieve the best SNR performance, the LTC2389-18 can be configured with fully differential (±4.096V) inputs. Pseudo-differential unipolar (0V to 4.096V) and bipolar (±2.048V) analog input ranges are supported, enabling low-power single-ended drive and reducing unwanted signals typically present on both inputs. The LTC2389-18 is well-suited for demanding designs requiring maximum signal swing at low power in noisy industrial environments.
The LTC2389-18 delivers superior DC performance including ±3LSB INL (maximum), ±10LSB offset error, and 18-bit lossless code resolution. The LTC2389-18 also features a precision 4.096V internal reference with a temperature coefficient of 20ppm/°C (maximum), enabling space savings in high-density designs. The LTC2389-18 consumes 162.5mW of power at 2.5Msps and features a shutdown mode that reduces power consumption to 75µW during non-conversion periods. True zero-latency operation enables accurate single-shot measurements without minimum sample rate requirements even after extended idle periods. The LTC2389-18 provides a flexible digital interface supporting 2.5Msps throughput on parallel interface and 1.9Msps on serial SPI interface with I/O voltage from 1.8V to 5V.
Following the LTC2389-18, a pin and software-compatible 16-bit 2.5Msps version, the LTC2389-16, delivering superior performance of 96dB SNR and ±0.75LSB INL will also be released shortly. Operating performance is guaranteed over the temperature range of -40ºC to 125ºC, and the products are offered in 48-pin 7mm × 7mm LQFP and QFN packages. Pricing for the LTC2389-16 and LTC2389-18 is $30.31 and $33.90 per unit respectively in quantities of 1,000. The DC1826A demo board for evaluating the LTC2389-18 and LTC2389-16 can be purchased through www.linear.com or regional sales offices. For detailed product information, refer to www.linear.com/product/LTC2389-18.

Photo Caption: 2.5Msps 18-bit, Zero-Latency SAR ADC with Flexible Analog Input Range

Product Features: LTC2389-18

• 2.5Msps throughput speed
• ±3LSB INL (maximum)
• 18-bit lossless code guaranteed
• Pin-compatible analog input ranges:
o ±VREF fully differential
o 0V to VREF pseudo-differential unipolar
o ±VREF/2 pseudo-differential bipolar
• 99.8dB (fully differential)/95.2dB (pseudo-differential) SNR (typical) at 2KHz fIN
• -116dB (fully differential)/-112dB (pseudo-differential) THD (typical) at 2KHz fIN
• Operating guarantee to 125°C
• Single 5V supply voltage
• Internal 20ppm/°C (maximum) reference
• Internal reference buffer
• 162.5mW power consumption at 2.5Msps
• No pipeline delay, no cycle latency
• 1.8V to 5V I/O voltage
• Parallel and serial I/O interface
• 48-pin 7mm x 7mm LQFP & QFN package