1 Features
• High gain bandwidth product: 8GHz
• Decompensated, gain ≥ 7V/V (stable)
• Low input voltage noise: 0.98nV/√Hz
• Slew rate: 2750V/μs
• Low Input capacitance:
– Common-mode: 0.6pF
– Differential: 0.2pF
• Wide input common-mode range:
– 0.4V from positive supply
– 1.1V from negative supply
• 3VPP total output swing
• Supply voltage range: 3.3V to 5.25V
• Quiescent current: 17.8mA
• Package: 8-pin WSON
– Bare die
• Temperature range: –40°C to +125°C

2 Applications
• Optical time domain reflectometry (OTDR)
• 3D scanner
• Laser distance measurement
• Solid-state scanning LIDAR
• Optical ToF position sensor
• Drone vision
• Industrial robot LIDAR
• Vacuum robot LIDAR
• Silicon photomultiplier (SiPM) buffer amplifier
• Photomultiplier tube post amplifier

3 Description
The OPA855 is a wideband, low-noise operational
amplifier with bipolar inputs for wideband
transimpedance and voltage amplifier applications.
When the device is configured as a transimpedance
amplifier (TIA), the 8GHz gain bandwidth product
(GBWP) enables high closed-loop bandwidths at
transimpedance gains of up to tens of kilohms.
The following graph shows the bandwidth and
noise performance of the OPA855 as a function of
the photodiode capacitance when the amplifier is
configured as a TIA. The total noise is calculated
along a bandwidth range extending from dc to the
calculated frequency (f) on the left scale. The OPA855
package has a feedback pin (FB) that simplifies the
feedback network connection between the input and
the output.
The OPA855 is optimized to operate in optical time-offlight
(ToF) systems where the OPA855 is used with
time-to-digital converters, such as the TDC7201. Use
the OPA855 to drive a high-speed analog-to-digital
converter (ADC) in high-resolution LIDAR systems
with a differential output amplifier, such as the
THS4541 or LMH5401 devices.