1 Features
• Gain bandwidth product: 300MHz
• Very-low (trimmed) supply current: 950μA
• Bandwidth: 90MHz (AV = 6V/V)
• High full-power bandwidth: 45MHz, 4VPP
• Negative rail input, rail-to-rail output
• Single-supply operating range: 2.7V to 5.4V
• 25°C input offset: ±125μV (maximum)
• Input offset voltage drift: < ±1.6μV/°C (maximum)
• Input voltage noise: 1.8nV/√Hz (> 200Hz)
• Input current noise: 1pA/√Hz (> 2000Hz)
• < 1μA shutdown current for power savings

2 Applications
• Low-power transimpedance amplifier
• Low-noise high-gain stage
• 12-bit to 16-bit low-power SAR ADC driver
• High-gain active filter design
• Ultrasonic flow meter

3 Description
The OPA838 decompensated voltage-feedback
operational amplifier provides a high, 300MHz
gain bandwidth product with 1.8nV/√Hz input noise
voltage, requiring only a trimmed 0.95mA supply
current. These features combine to provide an
extremely power-efficient device for photodiode
transimpedance designs and high-voltage gain
stages, which require the lowest input voltage noise
in signal receiver applications.
Operating at the minimum recommended noninverting
gain of 6V/V results in a 90MHz, –3dB bandwidth.
Extremely low input noise and offset voltage make
the OPA838 an excellent choice for high gains. Even
at a dc-coupled gain of 1000V/V, a 300kHz signal
bandwidth is available with a maximum output offset
voltage of ±125mV.
The single-channel OPA838 is available in 6-pin
SOT-23, 6-pin SC70, and 8-pin X2QFN packages, all
with a power shutdown feature. The OPA838 is also
available in a 5-pin SC70 package.