Datasheet AD8244 (Analog Devices) - 18
| Manufacturer | Analog Devices |
| Description | Single-Supply, Low Power, Precision FET Input Quad Buffer |
| Pages / Page | 20 / 18 — AD8244. Data Sheet. LOW NOISE, JFET INPUT BUFFER. 1/4. VOUT |
| Revision | A |
| File Format / Size | PDF / 556 Kb |
| Document Language | English |
AD8244. Data Sheet. LOW NOISE, JFET INPUT BUFFER. 1/4. VOUT
Model Line for this Datasheet
Text Version of Document
AD8244 Data Sheet LOW NOISE, JFET INPUT BUFFER R
The voltage noise of the AD8244 can be reduced by placing
1/4 O AD8244
multiple buffers in parallel. For example, two buffers in parallel reduce the voltage noise by √2, or all four buffers placed in parallel act as a buffer with ½ the noise. The trade-offs to this method are increased bias current, current noise, and input
R 1/4 O
capacitance. Place a small resistor, such as 50 Ω, between the
AD8244
outputs to avoid extra current flow due to the slight differences between each output. For less power sensitive applications, these
VOUT
50 Ω resistors can be omitted to boost the available output current.
RS R 1/4 O V AD8244 IN R 1/4 O AD8244
045 1689- 1 Figure 47. Reducing the Voltage Noise Rev. A | Page 18 of 20 Document Outline FEATURES APPLICATIONS PIN CONFIGURATION GENERAL DESCRIPTION TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS THEORY OF OPERATION OVERVIEW GUARDING INPUT PROTECTION LAYOUT CONSIDERATIONS DIFFERENTIAL SIGNAL CHAINS LOW OUTPUT IMPEDANCE vs. FREQUENCY APPLICATIONS INFORMATION ELECTROCARDIOGRAM (ECG) FILTERING Sallen-Key Low-Pass Filter Sallen-Key High-Pass Filter Twin-T Notch Filter PHOTODIODE AMPLIFIER LOW NOISE, JFET INPUT BUFFER OUTLINE DIMENSIONS ORDERING GUIDE
The voltage noise of the AD8244 can be reduced by placing
1/4 O AD8244
multiple buffers in parallel. For example, two buffers in parallel reduce the voltage noise by √2, or all four buffers placed in parallel act as a buffer with ½ the noise. The trade-offs to this method are increased bias current, current noise, and input
R 1/4 O
capacitance. Place a small resistor, such as 50 Ω, between the
AD8244
outputs to avoid extra current flow due to the slight differences between each output. For less power sensitive applications, these
VOUT
50 Ω resistors can be omitted to boost the available output current.
RS R 1/4 O V AD8244 IN R 1/4 O AD8244
045 1689- 1 Figure 47. Reducing the Voltage Noise Rev. A | Page 18 of 20 Document Outline FEATURES APPLICATIONS PIN CONFIGURATION GENERAL DESCRIPTION TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS THEORY OF OPERATION OVERVIEW GUARDING INPUT PROTECTION LAYOUT CONSIDERATIONS DIFFERENTIAL SIGNAL CHAINS LOW OUTPUT IMPEDANCE vs. FREQUENCY APPLICATIONS INFORMATION ELECTROCARDIOGRAM (ECG) FILTERING Sallen-Key Low-Pass Filter Sallen-Key High-Pass Filter Twin-T Notch Filter PHOTODIODE AMPLIFIER LOW NOISE, JFET INPUT BUFFER OUTLINE DIMENSIONS ORDERING GUIDE
