Datasheet AD795 (Analog Devices) - 7

Data Sheet AD795 1.00 1k NOISE BANDWIDTH: 0.1Hz TO 10Hz 0.95 ) ) A 0.90 -p (p p 100 V NT 0.85 E (µ E IS 0.80 O CURR N AS E G 0.75 BI A T 10 UT L 0.70 VO INP 0.65 0.60 1
3 10
–15 –10 –5 0 5 10 15
0
1k 10k 100k 1M 10M 100M 1G
01 5- 5-
COMMON-MODE VOLTAGE (V)
84
SOURCE RESISTANCE (Ω)
84 00 00 Figure 10. Input Bias Current vs. Common-Mode Voltage Figure 13. Input Voltage Noise vs. Source Resistance
10–4 50 SAMPLE SIZE = 344 10–5 –I +I 10–6 IN IN 40 S f = 0.1Hz TO 10Hz (A) 10–7 IT NT E UN 10–8 F 30 O E 10–9 CURR AG AS 10–10 NT 20 BI E UT RC 10–11 P E P IN 10–12 10 10–13 10–14 0
14
–6 –5 –4 –3 –2 –1 0 1 2 3 4 5 6
011
0 1 2 3
0 5- 5- 84
DIFFERENTIAL INPUT VOLTAGE (±V)
84
INPUT VOLTAGE NOISE (µV p-p)
00 00 Figure 11. Input Bias Current vs. Differential Input Voltage Figure 14. Typical Distribution of Input Voltage Noise
15.0 100 ) 1k f = 1kHz Hz / V ) (n T ) U 12.5 10 ) Hz Hz INP 100 V/ O T (n (fA/ D E VOLTAGE NOISE E IS IS O 10.0 1 RRE N E NO F E G NT A (RE T E 10 L CURRENT NOISE URRE IS VO 7.5 0.1 C NO E AG T L O V 5.0 0.01
2
1 –60 –40 –20 0 20 40 60 80 100 120 140
01
1 10 100 1k 10k 100k 1M 10M
015 5- 5-
TEMPERATURE (°C)
84
FREQUENCY (Hz)
84 00 00 Figure 12. Voltage and Current Noise Spectral Density vs. Temperature Figure 15. Input Voltage Noise Spectral Density Rev. D | Page 7 of 20 Document Outline FEATURES APPLICATIONS CONNECTION DIAGRAM GENERAL DESCRIPTION REVISION HISTORY SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE ESD CAUTION TYPICAL PERFORMANCE CHARACTERISTICS MINIMIZING INPUT CURRENT CIRCUIT BOARD NOTES OFFSET NULLING AC RESPONSE WITH HIGH VALUE SOURCE AND FEEDBACK RESISTANCE OVERLOAD ISSUES INPUT PROTECTION PREAMPLIFIER APPLICATIONS MINIMIZING NOISE CONTRIBUTIONS USING A T NETWORK A pH PROBE BUFFER AMPLIFIER OUTLINE DIMENSIONS ORDERING GUIDE