Check the listing for details. ANALOG DEVICES DC1685A Amplifier IC LTC6417 LTC2209 Combo Demo Board. Condition: New – Open box. Listed at 90.00 USD. 🔧 What the DC1685A Demo Board Is. 1.6 GHz differential ADC buffer (LTC6417) feeding. Manufacturer: Analog Devices. From the official demo manual Analog input: SMA (J6), 140 MHz, via 1:4 balun. We will try our best to resolve any issue.