(LTC2430 / LTC2431) 20-Bit No Latency Delta-Sigma ADCs

www.DataSheet4U.com LTC2430/LTC2431 20-Bit No Latency ∆ΣTM ADCs with Differential Input and Differential Reference FEATURES s s DESCRIPTIO s s s s s s s s Low Supply Current (200µA in Conversion Mode and 4µA in Autosleep Mode) Differential Input and Differential Reference with GND to VCC Common Mode Range 3ppm INL, No Missing Codes 10ppm Full-Scale Error and 1ppm Offset 0.56ppm Noise, 20.8 ENOBs No Latency: Digital Filter Settles in a Single Cycle. Each Conversion Is Accurate, Even After an Input Step Single Supply 2.7V to 5.5V Operation Internal Oscillator—No External Components Required 110dB Min, 50Hz/60Hz Notch Filter Pin Compatible with 24-Bit LTC2410/LTC2411 The LTC®2430/LTC2431 are 2.7V to 5.5V micropower 20-bit differential ∆Σ analog-to-digital converters with an integrated oscillator, 3ppm INL and 0.56ppm RMS noise. They use delta-sigma technology and provide single cycle settling time for multiplexed applications. Through a single pin, the LTC2430/LTC2431 can be configured for better than 110dB differential mode rejection at 50Hz or 60Hz ±2%, or they can be driven by an external oscillator for a user-defined rejection frequency. The internal oscillator requires no external frequency setting components. The converters accept any external differential reference voltage from 0.1V to VCC for flexible ratiometric and remote sensing measurement configurations. The fullscale differential input range is from – 0.5VREF to 0.5VREF. The reference common mode voltage, VREFCM, and the input common mode voltage, VINCM, may be independently set anywhere within GND to VCC. The DC common mode input rejection is better than 120dB. The LTC2430/LTC2431 communicate through a flexible 3-wire digital interface that is compatible with SPI and MICROWIRETM protocols. , LTC and LT are registered trademarks of Linear Technology Corporation. No Latency ∆Σ is a trademark of Linear Technology Corporation. MICROWIRE is a trademark of National Semiconductor Corporation. APPLICATIO S s s s s s s s s s Direct Sensor Digitizer Weight Scales Direct Temperature Measurement Gas Analyzers Strain Gauge Transducers Instrumentation Data Acquisition Industrial Process Control DVMs and Meters TYPICAL APPLICATIO S (VOUT + 0.25V) TO 20V VOUT 3V TO 5V 4.7µF 6 LT1790 1 2 4 0.1µF VCC TUE (ppm OF VREF) VCC 0.1µF FO LTC2431 REF + SCK REF – = INTERNAL OSC/50Hz REJECTION = EXTERNAL CLOCK SOURCE = INTERNAL OSC/60Hz REJECTION ANALOG INPUT RANGE –0.5VREF TO 0.5VREF IN + IN – GND SDO CS 24301 TA01 3-WIRE SPI INTERFACE U Total Unadjusted Error (VCC = 5V, VREF = 5V) 5 VCC = 5V 4 VREF = 5V VINCM = VINCM = 2.5V 3 F = GND O 2 1 0 –1 –2 –3 –4 –5 –2.5 –2 –1.5 –1 – 0.5 0 0.5 1 1.5 INPUT VOLTAGE (V) 2 2.5 –45°C 25°C 85°C 24301 G01 U U 24301f 1 LTC2430/LTC2431 ABSOLUTE AXI U RATI GS (Notes 1, 2) Digital Output Voltage to GND ..... – 0.3V to (VCC + 0.3V) Operating Temperature Range LTC2430C/LTC2431C .............................. 0°C to 70°C LTC2430I/LTC2431I ........................... – 40°C to 85°C Storage Temperature Range ................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C Supply Voltage (VCC) to GND .......................– 0.3V to 7V Analog Input Pins Voltage to GND ......................................... – 0.3V to (VCC + 0.3V) Reference Input Pins Voltage to GND ......................................... – 0.3V to (VCC + 0.3V) Digital Input Voltage to GND ........ – 0.3V to (VCC + 0.3V) PACKAGE/ORDER I FOR ATIO TOP VIEW GND VCC REF + ORDER PART NUMBER 16 GND 15 GND 14 FO 13 SCK 12 SDO 11 CS 10 GND 9 GND 1 2 3 4 5 6 7 8 LTC2430CGN LTC2430IGN REF – IN + IN – GND GND GN PART MARKING 2430 2430I GN PACKAGE 16-LEAD PLASTIC SSOP TJMAX = 125°C, θJA = 110°C/W Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS PARAMETER Resolution (No Missing Codes) Integral Nonlinearity The q denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. (Notes 3, 4) CONDITIONS 0.1V ≤ VREF ≤ VCC, – 0.5 • VREF ≤ VIN ≤ 0.5 • VREF (Note 5) 4.5V ≤ VCC ≤ 5.5V, REF + = 2.5V, REF– = GND, VINCM = 1.25V (Note 6) 5V ≤ VCC ≤ 5.5V, REF + = 5V, REF – = GND, VINCM = 2.5V (Note 6) REF + = 2.5V, REF – = GND, VINCM = 1.25V (Note 6) 2.5V ≤ REF + ≤ VCC, REF – = GND, GND ≤ IN + = IN – ≤ VCC (Note 14) 2.5V ≤ REF + ≤ VCC, REF – = GND, GND ≤ IN + = IN – ≤ VCC 2.5V ≤ REF + ≤ VCC, REF – = GND, IN + = 0.75REF +, IN – = 0.25 • REF + 2.5V ≤ REF + ≤ VCC, REF – = GND, IN + = 0.75REF +, IN – = 0.25 • REF + 2.5V ≤ REF + ≤ VCC, REF – = GND, IN + = 0.25 • REF+, IN – = 0.75 • REF + 2.5V ≤ REF + ≤ VCC, REF – = GND, IN + = 0.25 • REF+, IN – = 0.75 • REF + 4.5V ≤ VCC ≤ 5.5V, REF + = 2.5V, REF – = GND, VINCM = 1.25V 5V ≤ VCC ≤ 5.5V, REF + = 5V, REF – = GND, VINCM = 2.5V REF + = 2.5V, REF – = GND, VINCM = 1.25V 5V ≤ VCC ≤ 5.5V, REF + = 5V, VREF – = GND, GND ≤ IN – = IN + ≤ 5V, (Note 13) q q q Offset Error Offset Error Drift Positive Full-Scale Error Positive Full-Scale Error Drift Negative Full-Scale Error Negative Full-Scale Error Drift Total Unadjusted Error Output Noise 2 U U W WW U W ORDER PART NUMBER TOP VIEW VCC REF + REF – IN + IN – 1 2 3 4 5 10 9 8 7 6 FO SCK SDO CS GND LTC2431CMS LTC2431IMS MS PACKAGE 10-LEAD PLASTIC MSOP TJMAX = 125°C, θJA = 120°C/W MS PART MARKING LTXD LTXE MIN 20 TYP 2 3 10 5 50 MAX 20 20 UNITS Bits ppm of VREF ppm of VREF ppm of VREF µV nV/°C q 10 0.1 20 ppm of VREF ppm of VREF/°C q 10 0.1 3 6 15 2.8 20 ppm of VREF ppm of VREF/°C ppm of VREF ppm of VREF ppm of VREF µVRMS 24301f LTC2430/LTC2431 CO VERTER CHARACTERISTICS PARAMETER Input Common Mode Rejection DC Input Common Mode Rejection 60Hz ±2% Input Common Mode Rejection 50Hz ±2% Input Normal Mode Rejection 60Hz ±2% Input Normal Mode Rejection 50Hz ±2% Reference Common Mode Rejection DC Power Supply Rejection, DC Power Supply Rejection, 60Hz ±2% Power Supply Rejection, 50Hz ±2% CONDITIONS GND ≤ 2.5V ≤ REF + ≤ V The q denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. (Notes 3, 4) MIN q q q q q q A ALOG I PUT A D REFERE CE SYMBOL IN + IN – VIN REF + REF – VREF CS (IN +) CS (IN –) CS (REF +) CS (REF –) IDC_LEAK IDC_LEAK IDC_LEAK (IN +) (REF +) (REF –) IDC_LEAK (IN –) PARAMETER Absolute/Common Mode IN + Voltage Absolute/Common Mode IN – Voltage Input Differential Voltage Range (IN + – IN –) Absolute/Common Mode REF + Voltage Absolute/Common Mode REF – Voltage Reference Differential Voltage Range (REF + – REF –) IN + Sampling Capacitance IN – Sampling Capacitance REF + Sampling Capacitance REF – Sampling Capacitance IN + DC Leakage Current IN – DC Leakage Current REF + DC Leakage Current REF – DC Leakage Current The q denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. (Note 3) CONDITIONS q q q q q q U U U U TYP 120 MAX UNITS dB dB dB – CC, REF = GND, – = IN + ≤ 5V (Note 5) IN 110 140 140 110 110 130 2.5V ≤ REF+ ≤ VCC, REF – = GND, GND ≤ IN – = IN + ≤ 5V, (Notes 5, 7) 2.5V ≤ REF + ≤ VCC, REF – = GND, GND ≤ IN – = IN + ≤ 5V, (Notes 5, 8) (Notes 5, 7) (Notes 5, 8) 2.5V ≤ REF+ ≤ VCC, GND ≤ REF – ≤ 2.5V, VREF = 2.5V, IN – = IN + = GND (Note 5) REF + = 2.5V, REF – = GND, IN – = IN + = GND REF + = 2.5V, REF – REF + = 2.5V, REF – = GND, IN – = GND, IN – = IN + = GND, (Note 7) = IN + = GND, (Note 8) 140 140 140 110 120 120 dB dB dB dB dB dB U MIN GND – 0.3V GND – 0.3V – VREF/2 0.1 GND 0.1 TYP MAX VCC + 0.3V VCC + 0.3V VREF/2 VCC VCC – 0.1V VCC UNITS V V V V V V pF pF pF pF 1.5 1.5 1.5 1.5 CS = VCC, IN + = GND CS = VCC, IN – = VCC CS = VCC, REF + = VCC CS = VCC, REF – = GND q q q q –10 –10 –10 –10 1 1 1 1 10 10 10 10 nA nA nA nA 24301f 3 LTC2430/LTC2431 DIGITAL I PUTS A D DIGITAL OUTPUTS SYMBOL VIH VIL VIH VIL IIN IIN CIN CIN VOH VOL VOH VOL IOZ PARAMETER High Level Input Voltage CS, FO Low Level Input Voltage CS, FO High Level Input Voltage SCK Low Level Input Voltage SCK Digital Input Current CS, FO Digital Input Current SCK Digital Input Capacitance CS, FO Digital Input Capacitance SCK High Level Output Voltage SDO Low Level Output Voltage SDO High Level Output Voltage SCK Low Level Output Voltage SCK Hi-Z Output Leakage SDO (Note 9) IO = – 800µA IO = 1.6mA IO = – 800µA (Note 10) IO = 1.6mA (Note 10) q q q q q The q denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. (Note 3) CONDITIONS 2.7V ≤ VCC ≤ 5.5V 2.7V ≤ VCC ≤ 3.3V 4.5V ≤ VCC ≤ 5.5V 2.7V ≤ VCC ≤ 5.5V 2.7V ≤ VCC ≤ 5.5V (Note 9) 2.7V ≤ VCC ≤ 3.3V (Note 9) 4.5V ≤ VCC ≤ 5.5V (Note 9) 2.7V ≤ VCC ≤ 5.5V (Note 9) 0V ≤ VIN ≤ VCC 0V ≤ VIN ≤ VCC (Note 9) q q q q q q POWER REQUIRE E TS SYMBOL VCC ICC PARAMETER Supply Voltage Supply Current Conversion Mode Sleep Mode Sleep Mode The q denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. (Note 3) CONDITIONS q 4 UW U U MIN 2.5 2.0 TYP MAX UNITS V V 0.8 0.6 2.5 2.0 0.8 0.6 –10 –10 10 10 VCC – 0.5V 0.4 VCC – 0.5V 0.4 –10 10 10 10 V V V V V V µA µA pF pF V V V V µA MIN 2.7 TYP MAX 5.5 UNITS V µA µA µA CS = 0V (Note 12) CS = VCC (Note 12) CS = VCC, 2.7V ≤ VCC ≤ 3.3V (Note 12) q q 200 4 2 300 10 24301f LTC2430/LTC2431 TI I G CHARACTERISTICS SYMBOL fEOSC tHEO tLEO tCONV PARAMETER External Oscillator Frequency Range External Oscillator High Period External Oscillator Low Period Conversion Time FO = 0V FO = VCC External Oscillator (