Datasheet LTC1287 (Analog Devices) - 3

LTC1287
AC CHARACTERISTICS The
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denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25
°
C. (Note 3) LTC1287B/LTC1287C SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
thDO Time Output Data Remains Valid After CLK↓ 50 ns tf DOUT Fall Time See Test Circuits ● 40 100 ns tr DOUT Rise Time See Test Circuits ● 40 100 ns tWHCLK CLK High Time VCC = 3V (Note 6) 600 ns tWLCLK CLK Low Time VCC = 3V (Note 6) 800 ns tsuCS Setup Time, CS↓ Before CLK↑ VCC = 3V (Note 6) 100 ns tWHCS CS High Time Between Data Transfer Cycles VCC = 3V (Note 6) 5.0 µs tWLCS CS Low Time During Data Transfer VCC = 3V (Note 6) 14 CLK Cycles CIN Input Capacitance Analog Inputs On Channel 100 pF Analog Inputs Off Channel 5 pF Digital Inputs 5 pF
U DIGITAL A D DC ELECTRICAL CH C ARA TER S I TICS The
●
denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25
°
C. (Note 3) LTC1287B/LTC1287C SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VIH High Level Input Voltage VCC = 3.6V ● 2.1 V VIL Low Level Input Voltage VCC = 3.0V ● 0.45 V IIH High Level Input Current VIN = VCC ● 2.5 µA IIL Low Level Input Current VIN = 0V ● –2.5 µA VOH High Level Output Voltage VCC = 3.0V, IO = 20µA 2.90 V IO = 400µA ● 2.7 2.85 V VOL Low Level Output Voltage VCC = 3.0V, IO = 20µA 0.05 V IO = 400µA ● 0.10 0.3 V IOZ High Z Output Leakage VOUT = VCC, CS High ● 3 µA VOUT = 0V, CS High ● –3 µA ISOURCE Output Source Current VOUT = 0V –10 mA ISINK Output Sink Current VOUT = VCC 9 mA ICC Positive Supply Current CS High ● 1.5 5 mA IREF Reference Current VREF = 2.5V ● 10 50 µA
Note 1:
Absolute Maximum Ratings are those values beyond which the life
Note 7:
Two on-chip diodes are tied to each analog input which will of a device may be impaired. conduct for analog voltages one diode drop below GND or one diode drop
Note 2:
All voltage values are with respect to ground (unless otherwise above VCC. Be careful during testing at low VCC levels, as high level analog noted). inputs can cause this input diode to conduct, especially at elevated temperature, and cause errors for inputs near full scale. This spec allows
Note 3:
VCC = 3V, VREF = 2.5V, CLK = 500kHz unless otherwise specified. 50mV forward bias of either diode. This means that as long as the analog
Note 4:
One LSB is equal to VREF divided by 4096. For example, when VREF input does not exceed the supply voltage by more than 50mV, the output = 2.5V, 1LSB = 2.5V/4096 = 0.61mV. code will be correct.
Note 5:
Integral nonlinearity error is defined as the deviation of a code
Note 8:
Channel leakage current is measured after the channel selection. from a straight line passing through the actual endpoints of the transfer
Note 9:
Increased leakage currents at elevated temperatures cause the curve. The deviation is measured from the center of the quantization band. S/H to droop, therefore it is recommended that f
Note 6:
Recommended operating conditions. CLK ≥ 30kHz at 85°C and fCLK ≥ 3kHz at 25°C. 1287fa 3