LTC1594/LTC1598 AC CHARACTERISTICS The ● denotes the specifications which apply over the full operating temperature range,otherwise specifications are at TA = 25 ° C. (Note 5)SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITS tSMPL Analog Input Sample Time See Figure 1 in Applications Information 1.5 CLK Cycles fSMPL(MAX) Maximum Sampling Frequency See Figure 1 in Applications Information ● 16.8 kHz tCONV Conversion Time See Figure 1 in Applications Information 12 CLK Cycles tdDO Delay Time, CLK↓ to DOUT Data Valid See Test Circuits ● 250 600 ns tdis Delay Time, CS↑ to DOUT Hi-Z See Test Circuits ● 135 300 ns ten Delay Time, CLK↓ to DOUT Enabled See Test Circuits ● 75 200 ns thDO Time Output Data Remains Valid After CLK↓ CLOAD = 100pF 230 ns tf DOUT Fall Time See Test Circuits ● 50 150 ns tr DOUT Rise Time See Test Circuits ● 50 150 ns tON Enable Turn-On Time See Figure 1 in Applications Information ● 260 700 ns tOFF Enable Turn-Off Time See Figure 2 in Applications Information ● 100 300 ns tOPEN Break-Before-Make Interval ● 35 160 ns CIN Input Capacitance Analog Inputs On-Channel 20 pF Off-Channel 5 pF Digital Input 5 pF Note 1: Stresses beyond those listed under Absolute Maximum Ratings Note 6: Linearity error is specified between the actual end points of the may cause permanent damage to the device. Exposure to any Absolute A/D transfer curve. Maximum Rating condition for extended periods may affect device Note 7: Two on-chip diodes are tied to each reference and analog input reliability and lifetime. which will conduct for reference or analog input voltages one diode drop Note 2: All voltage values are with respect to GND. below GND or one diode drop above VCC. This spec allows 50mV forward Note 3: These devices are specified at 5V. Consult factory for 3V bias of either diode for 4.5V ≤ VCC ≤ 5.5V. This means that as long as the specified devices (LTC1594L/LTC1598L). reference or analog input does not exceed the supply voltage by more than Note 4: Increased leakage currents at elevated temperatures cause the S/H 50mV, the output code will be correct. To achieve an absolute 0V to 5V to droop, therefore it is recommended that f input voltage range, it will therefore require a minimum supply voltage of CLK ≥ 160kHz at 85°C, f 4.950V over initial tolerance, temperature variations and loading. CLK ≥ 75kHz at 70°C and fCLK ≥ 1kHz at 25°C. Note 5: V Note 8: Recommended operating condition. Not 100% production tested. CC = 5V, VREF = 5V and CLK = 320kHz unless otherwise specified. CSADC and CSMUX pins are tied together during the test. Note 9: Channel leakage current is measured after the channel selection. WUTYPICAL PERFORMANCE CHARACTERISTICSSupply Current vs Sample RateSupply Current vs TemperatureReference Current vs Temperature 1000 450 95.0 TA = 25°C T VCC = VREF = 5V A = 25°C VCC = 5V V fSMPL = 16.8kHz CC = VREF = 5V V 94.5 REF = 5V f fCLK = 320kHz 400 CLK = 320kHz fCLK = 320kHz fSMPL = 16.8kHz μA) μA) μA) 100 94.0 350 93.5 300 10 93.0 SUPPLY CURRENT ( SUPPLY CURRENT ( REFERENCE CURRENT ( 250 92.5 1 200 92.0 0.1 1 10 100 – 55 – 35 –15 5 25 45 65 85 105 125 – 55 – 35 –15 5 25 45 65 85 105 125 SAMPLE FREQUENCY (kHz) TEMPERATURE (°C) TEMPERATURE (°C) 1594/98 G01 1594/98 G02 1594/98 G03 15948fb 4