OPA818IDRGR

The OPA818 is a decompensated (stable gain = 7V/V) voltage-feedback operational amplifier with a low-noise junction field-effect transistor (JFET) input stage. It combines high gain-bandwidth with a wide power supply voltage range of 6V to 13V, making it suitable for high-speed, wide dynamic range applications. This amplifier is fabricated using a proprietary high-speed silicon-germanium (SiGe) process, offering significantly better performance than other high-speed FET-input amplifiers. The fast slew rate (1400V/μs) provides higher large-signal bandwidth and low distortion. With a gain-bandwidth of 2.7GHz, a low total input capacitance of 2.4pF, and a noise of 2.2nV/√Hz, the OPA818 is very versatile. The wideband TIA photodiode amplifier can be used in optical test and communication equipment, as well as in many medical, scientific, and industrial instruments. The OPA818 can achieve a signal bandwidth of over 85MHz, a TIA gain (RF) of 20kΩ, a photodiode capacitance (CD) of 0.5pF, and a wide output swing in a TIA configuration. The decompensated low-noise architecture with picoampere input bias current is also well-suited for high-gain test and measurement applications with variable or high source impedance. Although it is typically stable at gains ≥7V/V, the OPA818 can also be used in lower-gain applications by utilizing noise gain shaping techniques. The OPA818 is available in an 8-pin WSON package with an exposed thermal pad. This device operates over the industrial temperature range of -40°C to +85°C.

Applications

• Wideband transimpedance amplifier (TIA)
• Wafer scanning equipment
• Optical communication modules
• Optical time-domain reflectometry (OTDR)
• High-speed, high-gain data acquisition
• Test and measurement front-end
• Medical and chemical analyzers
• High-speed optical front-end

Key features

• High Speed:
• Gain Bandwidth Product: 2.7GHz
• Bandwidth (G = 7V/V): 790MHz
• Large Signal Bandwidth (2VP-P): 400MHz
• Slew Rate: 1400V/μs
• Decompensated Gain: 7V/V (Stable)
• Low Noise:
• Input Voltage Noise: 2.2nV/√Hz
• Input Current Noise: 2.5fA/√Hz (f = 10kHz)
• Input Bias Current: 4pA (Typical)
• Low Input Capacitance:
• Common Mode: 1.9pF
• Differential Mode: 0.5pF
• Low Distortion (G = 7V/V, RL = 1kΩ, V0 = 2VP-P):
• HD2, HD3 at 1MHz: -90dBc, -96dBc
• HD2, HD3 at 50MHz: -57dBc, -72dBc
• Wide Supply Voltage Range: 6V to 13V
• Output Swing: 8VP-P (VS = 10V)
• Supply Current: 27.7mA
• Shutdown Supply Current: 27μA
• Temperature Range: -40°C to +85°C