LTC1090 Single Chip 10-Bit Data Acquisition System FEATURES DESCRIPTIO Software Programmable Features: The LTC 1090 is a data acquisition component which Unipolar/Bipolar Conversions contains a serial I/O successive approximation A/D con- TM 4 Differential/8 Single Ended Inputs verter. It uses LTCMOS switched capacitor technology MSB or LSB First Data Sequence to perform either 10-bit unipolar, or 9-bit plus sign bipolar Variable Data Word Length A/D conversions. The 8-channel input multiplexer can be Built-In Sample and Hold configured for either single ended or differential inputs (or Single Supply 5V, 10V or 5V Operation combinations thereof). An on-chip sample and hold is Direct 4 Wire Interface to Most MPU Serial Ports and included for all single ended input channels. All MPU Parallel Ports The serial I/O is designed to be compatible with industry 30kHz Maximum Throughput Rate standard full duplex serial interfaces. It allows either MSB or LSB first data and automatically provides 2s U complement output coding in the bipolar mode. The KEY SPECIFICATIO S output data word can be programmed for a length of 8, 10, Resolution: 10 Bits 12 or 16 bits. This allows easy interface to shift registers Total Unadjusted Error (LTC1090A): 1/2LSB Max and a variety of processors. Conversion Time: 22s The LTC1090A is specified with total unadjusted error Supply Current: 2.5mA Max, 1.0mA Typ (including the effects of offset, linearity and gain errors) , LTC and LT are registered trademarks of Linear Technology Corporation. less than 0.5LSB. LTCMOS is a trademark of Linear Technology Corp. The LTC1090 is specified with offset and linearity less than 0.5LSB but with a gain error limit of 2LSB for applications where gain is adjustable or less critical. TYPICAL APPLICATIO FOR 8051 CODE SEE APPLICATIONS INFORMATION SECTION LTC1090 MPU (e.g., 8051) Linearity Plot DIFFERENTIAL INPUT 1.0 5V BIPOLAR INPUT 0.5 5V 5V D P1.1 0.0 OUT D P1.2 IN T SCLK P1.3 0.5 UNIPOLAR INPUTS CS P1.4 SERIAL DATA LINK 1.0 0 512 1024 OUTPUT CODE LTC1090 TA02 (+) UNIPOLAR () INPUT LTC1090 TA01 5V 1090fc 1 ERROR (LSBs) U ULTC1090 UUW ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO (Notes 1 and 2) TOP VIEW ORDER PART Supply Voltage (V ) to GND or V ................................ 12V CC 1 20 V CH0 CC NUMBER Negative Supply Voltage (V ) ..................... 6V to GND 2 19 ACLK CH1 Voltage: 3 18 SCLK CH2 LTC1090ACN Analog and Reference 4 17 D CH3 IN LTC1090CN Inputs .................................... (V ) 0.3V to V 0.3V 5 16 D CC CH4 OUT LTC1090CSW Digital Inputs ......................................... 0.3V to 12V 6 15 CS CH5 + 7 14 REF Digital Outputs .............................. 0.3V to V 0.3V CH6 CC 8 13 REF CH7 Power Dissipation.............................................. 500mW 9 12 V COM Operating Temperature Range 10 11 AGND DGND LTC1090AC/LTC1090C ........................40C to 85C LTC1090AM/LTC1090M (OBSOLETE) ......55C to 125C SW PACKAGE N PACKAGE 20-LEAD PLASTIC SO WIDE 20-LEAD PDIP Storage Temperature Range ................. 65C to 150C T = 150C, = 70C/W JMAX JA Lead Temperature (Soldering, 10 sec).................. 300C T = 110C, = 90C/W JMAX JA LTC1090AMJ J PACKAGE 20-LEAD CERDIP LTC1090MJ T = 150C = 70 C/W JMAX JA LTC1090ACJ LTC1090CJ OBSOLETE PACKAGE Consider the SW or N Package for Alternate Source LTC1090 POI01 Consult LTC Marketing for parts specified with wider operating temperature ranges. RECO E DED OPERATI G CO DITIO S LTC1090/LTC1090A SYMBOL PARAMETER CONDITIONS MIN MAX UNITS V Positive Supply Voltage V = 0V 4.5 10 V CC V Negative Supply Voltage V = 5V 5.5 0 V CC f Shift Clock Frequency V = 5V 0 1.0 MHz SCLK CC f A/D Clock Frequency V = 5V 25C 0.01 2.0 MHz ACLK CC 85C 0.05 2.0 125C 0.25 2.0 t Total Cycle Time See Operating Sequence 10 SCLK + Cycles CYC 48 ACLK t Hold Time, CS Low After Last SCLK V = 5V 0 ns hCS CC t Hold Time, D After SCLK V = 5V 150 ns hDI IN CC t Setup Time CS Before Clocking in First Address Bit (Note 9) V = 5V 2 ACLK Cycles suCS CC 1s t Setup Time, D Stable Before SCLK V = 5V 400 ns suDI IN CC t ACLK High Time V = 5V 127 ns WHACLK CC t ACLK Low Time V = 5V 200 ns WLACLK CC t CS High Time During Conversion V = 5V 44 ACLK WHCS CC Cycles 1090fc 2 UWU U U W U WWW