QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 1337 8-CHANNEL, 12-BIT, SAR ADC WITH I2C INTERFACE LTC2309 DESCRIPTION Demonstration circuit 1337 features the LTC2309, a low noise, low power, 8-Channel, 12-Bit, successive approximation ADC with 2 an I C compatible serial interface. The LTC2309 is available in a 24-pin 4mm x 4mm QFN package. DC1337 demonstrates the DC performance of the LTC2309 in conjunction with the DC590B Quick Eval data collection board. Alternatively, by connecting the DC1337 into a customer application the performance of the LTC2309 can be evaluated directly in that circuit. Design files for this circuit board are available. Call the LTC factory. LTC is a trademark of Linear Technology Corporation FIGURE 1. DC1337A 1 QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 1337 8-CHANNEL, 12-BIT, SAR ADC WITH I2C INTERFACE DC590B QUICK START PROCEDURE Connect DC1337 to a DC590B USB serial controller using the supplied 14-conductor ribbon cable. Make sure the VCCIO jumper of the DC590B is in the 5V position. Connect DC590B to a host PC with a standard USB A/B cable. Apply analog input voltage to CH0-CH7 on connector J1. Run the evaluation software supplied with DC590B or download it from www.linear.com. The correct control panel will be loaded automatically. Click the COLLECT (Figure 2) button to begin reading the ADC Ch0-Ch3. Press the Page 1 Button to toggle to Page 2. This displays Ch4Ch7. This button toggles between the two displays. The Help menu contains information on Data Logging the ADC results. The Tools menu has the Data Logging option as well as options for changing the number of points displayed, the number of points in an average and whether the data is displayed in LSBs or Volts. The View menu can be used to access the LTC2309 product page. If the Quick Eval program is started without the demo board attached to DC590B, the Tools menu can be used to check for updates and automatically install them. DC 1337 requires at least version K71 of the Quick Eval software. HARDWARE SET UP SIGNAL CONNECTIONS See Figure 1 for locations. J1 Connector for CH0-CH7, COM and BIAS/2. Limit input voltage swings to GNDAVDD. For optimum performance, the input should be bandlimited to the frequencies of interest. 2 J2 AD0 I C address line. Set to GND for operation with supplied software. 2 J3 AD1 I C address line. Set to GND for operation with supplied software. J4 COM Common pin for single ended ADC conversions. Can be set to GND or left floating so that COM can be driven by J1. J5 DC590 interface connector. Provides power and I2C interface to DC1337. J6 BIAS Selects between Refcomp and an external bias voltage to drive the Bias/2 line. Bias/2 is designed to set a center point for the minus input during bipolar operation. EXT_BIAS External Bias connection. This can be used to drive the BIAS/2 line through a 2:1 divider. To use this pin put jumper J6 in the EXT position and apply desired bias voltage. 5V Five volt supply line for DC1337. Use this line only if DC590 is not used GND Ground line for DC1337 2 SDA I C bidirectional data line. Controlled by DC590B if connected. 2 SCL I C clock line. Controlled by DC590B if connected. VREF Connected to ADC Vref pin. REFCOMP Connected to ADC Refcomp pin. BIAS/2 Bias voltage/2 (Refcomp or Ext) 2 QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 1337 8-CHANNEL, 12-BIT, SAR ADC WITH I2C INTERFACE USING DC1337 WITHOUT DC590 Interface signals SDA and SCL and power are normally provided to DC1337 by DC590. If you use this board without DC590, it is the users responsibility to connect a 5V power supply and ground as well as generating SDA and SCL. These signals can be provided through the 14-pin ribbon cable connector. See schematic for pinout See LTC2309 Data Sheet for information on driving SDA and SCL. Figure 2. DC1337 Quick Eval Screenshot 3 QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 1337 8-CHANNEL, 12-BIT, SAR ADC WITH I2C INTERFACE NC 14 EESDA EEVCC EESCL EEGND 12 9 10 11 MISO MOSI/SDA 5 CS SCK/SCL 7 4 6 5V VUNREG F 7C p47 F 6C p47 Fp 74 11 C Fp 74 5 SDA A1 A0 FFGND 1 2 WP A2 3 7 01 pF7 C 4 100 F 9C p74 100 20 18 16 14 R9 100 R7 12 21 C R8 100 10 R5 100 R6 100 R4 8 6 F 13C p47 SA IB _T XE E8 E6 19 17 15 13 11 9 7 5 3 J1 D N G 1 V5 E2 E1 5V 4 R3 100 R2 100 F 5C p47 100 1% 6 G ND FLT 22 23 24 1 2 3 4 5 6 2 COM 1 F 8C 7p4 R1 71 Fu1 C 3 4J 1% R12 1% R11 1 REFCOM P EXT 21 M H0C H1C H2C H3C H4C H5C H6C H7C O C K9 .94 3 BIAS 15 16 17 49.9 1% K9 .94 F 15C 0u1 2 1% E7 E5 GND 9 LTC2309CUF SCL 3 5V FLT 3 5V 10 5V 5V 14 11 5V 6J 2 18 4C 19 13 1C DDV D 20 12 Fu 1. 0 81 F C u.1 0 25 Fu 10 31 K R 9.9 4 8 Fu .10 2C P MOCF E R DA P DN G DN G DN G DN G DN G DN G 41 K R 9.9 4 61 Fu0 C 1 7 DDV A D DV A 41 F2u. C 2 AD LC 1D 0D S S A AF E R V 24LC025-I/ST G ND 5V FLT AD1 1 2 4 J2 AD0 5V 2 1 J3 4 8 1U 01 R VCC uF1 .0 3C P M O C FE R FE R V GND 2U 4 51 9K.9 R 4 1% 5V 2 J5 GND 1 GND 3 E4 GND 8 E3 LC S 13 AD S 2/ SA IB 4