2-Channel Differential Input 16-Bit No Latency DS ADC

www.DataSheet4U.com LTC2436-1 2-Channel Differential Input 16-Bit No Latency ∆Σ ADC FEATURES s s s DESCRIPTIO s s s s s s s s s 2-Channel Differential Input with Automatic Channel Selection (Ping-Pong) Low Supply Current: 200µA, 4µA in Autosleep Differential Input and Differential Reference with GND to VCC Common Mode Range 0.12LSB INL, No Missing Codes 0.16LSB Full-Scale Error and 0.006LSB Offset 800nV RMS Noise, Independent of VREF No Latency: Digital Filter Settles in a Single Cycle and Each Channel Conversion is Accurate Internal Oscillator—No External Components Required 87dB Min, 50Hz and 60Hz Notch Filter Narrow SSOP-16 Package Single Supply 2.7V to 5.5V Operation Pin Compatible with the 24-Bit LTC2412 The LTC®2436-1 is a 2-channel differential input micropower 16-bit No Latency ∆ΣTM analog-to-digital converter with an integrated oscillator. It provides 0.5LSB INL and 800nV RMS noise independent of VREF. The two differential channels convert alternately with a channel identification included in the conversion result. It uses delta-sigma technology and provides single conversion settling of the digital filter. Through a single pin, the LTC2436-1 can be configured for better than 87dB input differential mode rejection at 50Hz and 60Hz ±2%, or it can be driven by an external oscillator for a user defined rejection frequency. The internal oscillator requires no external frequency setting components. The converter accepts 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 – 0.5 • VREF to 0.5 • VREF. The reference common mode voltage, VREFCM, and the input common mode voltage, VINCM, may be independently set anywhere between GND and VCC. The DC common mode input rejection is better than 140dB. The LTC2436-1 communicates through a flexible 3-wire digital interface which 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 Direct Sensor Digitizer Weight Scales Direct Temperature Measurement Gas Analyzers Strain-Gage Transducers Instrumentation Data Acquisition Industrial Process Control TYPICAL APPLICATIO 5V REF 1µF 4.9k (100mV) 100Ω 1 2 4 VCC + EFFECTIVE RESOLUTION (µV)* FO 14 REF CH0+ LTC2436-1 CH0– REF – CH1 + = EXTERNAL CLOCK SOURCE = INTERNAL OSC/SIMULTANEOUS 50Hz/60Hz REJECTION 50 40 30 20 10 0 0 5 4 3 2 VREF (V) 24361 TA02 *COMBINES EFFECTS OF PEAK-TO-PEAK NOISE AND 16-BIT STEP SIZE (VREF/216) 1 5 THERMOCOUPLE 3 6 7 8, 9, 10, 15, 16 SCK SDO CS 13 12 11 3-WIRE SPI INTERFACE CH1– GND 24361 TA01 U Effective Resolution vs VREF 90 80 70 60 U U 24361f 1 LTC2436-1 ABSOLUTE (Notes 1, 2) AXI U RATI GS PACKAGE/ORDER I FOR ATIO TOP VIEW VCC REF + REF – CH0+ CH0– CH1+ CH1– GND 1 2 3 4 5 6 7 8 16 GND 15 GND 14 FO 13 SCK 12 SDO 11 CS 10 GND 9 GND Supply Voltage (VCC) to GND .......................– 0.3V to 7V Analog Input Voltage to GND .................................... – 0.3V to (VCC + 0.3V) Reference Input Voltage to GND .................................... – 0.3V to (VCC + 0.3V) Digital Input Voltage to GND ........ – 0.3V to (VCC + 0.3V) Digital Output Voltage to GND ..... – 0.3V to (VCC + 0.3V) Operating Temperature Range LTC2436-1C ............................................ 0°C to 70°C LTC2436-1I ........................................ – 40°C to 85°C Storage Temperature Range ................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C ORDER PART NUMBER LTC2436-1CGN LTC2436-1IGN GN PART MARKING 24361 24361I 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 CONDITIONS The q denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. (Notes 3, 4) MIN q TYP 0.06 0.12 0.30 0.006 10 MAX UNITS Bits LSB LSB LSB LSB nV/°C 0.1V ≤ VREF ≤ VCC, –0.5 • VREF ≤ VIN ≤ 0.5 • VREF, (Note 5) 16 3 1 5V ≤ VCC ≤ 5.5V, REF+ = 2.5V, REF– = GND, VINCM = 1.25V, (Note 6) q 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 13) 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+ 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, (Note 6) 5V ≤ VCC ≤ 5.5V, REF+ = 5V, REF – = GND, GND ≤ IN– = IN+ ≤ VCC, (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 0.16 0.03 0.16 0.03 0.20 0.20 0.25 0.8 3 ppm of VREF/°C 3 LSB ppm of VREF/°C 3 3 3 LSB LSB LSB µVRMS Output Noise 2 U LSB 24361f W U U W W W LTC2436-1 CO VERTER CHARACTERISTICS PARAMETER Input Common Mode Rejection DC Input Common Mode Rejection 49Hz to 61.2Hz Input Normal Mode Rejection 49Hz to 61.2Hz Reference Common Mode Rejection DC Power Supply Rejection, DC Power Supply Rejection, Simultaneous 50Hz/60Hz ±2% CONDITIONS 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 A ALOG I PUT A D REFERE CE SYMBOL IN+ IN– VIN REF+ REF– VREF CS (IN+) CS CS (IN–) (REF+) (IN+) (IN–) (REF–) 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+ IN– DC Leakage Current 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 CS (REF–) IDC_LEAK IDC_LEAK IDC_LEAK IDC_LEAK (REF+) REF+ DC Leakage Current REF– DC Leakage Current U U U U TYP 140 MAX UNITS dB dB dB 2.5V ≤ REF+ ≤ VCC, REF– = GND, GND ≤ IN– = IN+ ≤ VCC (Note 5) 2.5V ≤ REF+ ≤ VCC, REF– = GND, GND ≤ IN – = IN+ ≤ VCC, (Notes 5, 7) (Note 5, 7) 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– = GND, IN– = IN+ = GND, (Note 7) 130 140 87 130 140 120 120 dB dB dB U MIN GND – 0.3 GND – 0.3 –VREF/2 0.1 GND 0.1 TYP MAX VCC + 0.3 VCC + 0.3 VREF/2 VCC VCC – 0.1 VCC UNITS V V V V V V pF pF pF pF 18 18 18 18 CS = VCC CS = VCC CS = VCC = 5V, IN+ = GND = 5V, IN – = 5.5V = 5V, REF – = GND q q q q –10 –10 –10 –10 1 1 1 1 10 10 10 10 nA nA nA nA CS = VCC = 5V, REF+ = 5.5V 24361f 3 LTC2436-1 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 8) IO = –800µA IO = 1.6mA IO = –800µA (Note 9) IO = 1.6mA (Note 9) 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 8) 2.7V ≤ VCC ≤ 3.3V (Note 8) 4.5V ≤ VCC ≤ 5.5V (Note 8) 2.7V ≤ VCC ≤ 5.5V (Note 8) 0V ≤ VIN ≤ VCC 0V ≤ VIN ≤ VCC (Note 8) 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 U W 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 – 0.5 0.4 VCC – 0.5 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 14) CS = VCC (Notes 11, 14) CS = VCC, 2.7V ≤ VCC ≤ 3.3V (Notes 11, 14) q q 200 4 2 300 13 24361f LTC2436-1 TI I G CHARACTERISTICS SYMBOL fEOSC tHEO tLEO tCONV fISCK DISCK fESCK tLESCK tHESCK tDOUT_ISCK tDOUT_ESCK t1 t2 t3 t4 tKQMAX tKQMIN t5 t6 PARAMETER External Oscillator Frequency Range External Oscillator High Period External Oscillator Low Period Conversion Time Internal SCK Frequency Internal SCK Duty Cycle External SCK Frequency Range External SCK Low Period External SCK High Period Internal SCK 19-Bit Data Output Time External SCK 19-Bit Data Output Time CS ↓ to SDO Low Z CS ↑ to SDO High Z CS ↓ to SCK ↓ CS ↓ to SCK ↑ SCK ↓ to SDO Valid SDO Hold After SCK ↓ SCK Set-Up Before CS ↓ SCK Hold After CS ↓ (Note 5) (Note 9) (Note 8) FO = 0V External Oscillator (Note 10) Internal Oscillator (Note