DEMO MANUAL DC979A LTC2442 24-Bit High Speed 4-Channel DS ADC with Integrated Amplifier Description easy evaluation of the LTC2442 and may be connected The LTC 2442 is a 2-/4-channel, high speed, 24-bit S directly to the target applications analog signals while ADC with ten selectable speed/resolution modes from using the DC590 USB serial controller board and supplied 6.9Hz/200nV to 3.5kHz/25V . Key DC specifica- RMS RMS software to measure performance. The exposed ground tions include 4ppm maximum INL, 5V offset, 10ppm full- planes allow proper grounding to prototype circuitry. After scale error and 20nV/C offset drift. In the 6.9Hz/200nV RMS evaluating with LTCs software, the digital signals can be mode, an input normal mode rejection of 50Hz and 60Hz connected to the applications processor/controller for noise is better than 87dB. The accuracy (offset, full-scale, development of the serial interface. linearity, drift) and power dissipation are independent of the speed selected. The LTC2442 incorporates rail-to-rail Design files for this circuit board are available at buffer amplifiers for true high impedance inputs. DEMO MANUAL DC979A Quick s Dp 1. Connect the DC979A to a DC590 USB serial controller 5. Click the slider at the bottom of the strip chart display using the supplied 14-conductor ribbon cable. to change the oversample ratio (OSR) which will in turn change the data output rate. 2. Connect the DC590 to the host PC with a standard USB A/B cable. Tools are available for logging data, changing reference voltage, changing the number of points in the strip chart 3. Run the QuikEval evaluation software supplied with the and histogram, and changing the number of points aver- DC590 or download it from www.linear.com/software. aged for the DVM display. The correct program will be loaded automatically. 4. Click the COLLECT button to start reading the input voltage. Figure 2. Quikeval software Dh s Jumpers Jp6, Jp7: Select the positive and negative supply volt- ages for the onboard amplifier. Supplies can be V and + CC Jp1, Jp2: Select the source for REF and REF , respect- GND or +10 and 5V from the onboard LTC1983 charge + ively. REF can be 5.00V from the onboard LT 1236 pump. To use an external power supply, REMOVE JP6 reference (default) or supplied externally. REF can be + and JP7 and connect the external supply to the V , GND, ground (0V, default) or supplied externally. and V turrets. Jp3: Select source for analog COM input, either tied to Jp4: Trigger mode, either normal (default) or externally ground or supplied externally to the COM turret post. triggered (TRIG). DC979Af 2 etup ware ar ure roce tart