OPA657

1.6GHz、低噪声、FET 输入运算放大器

The device combines a high-gain bandwidth, low-distortion, voltage-feedback operational amplifier with a low-voltage noise JFET-input stage to offer a very high dynamic range amplifier for high-precision ADC analog-to-digital converter driving or wideband transimpedance applications. Photodiode applications see improved noise and bandwidth using this decompensated, high-gain bandwidth amplifier.

Very low level signals can be significantly amplified in a single OPA657 gain stage with exceptional bandwidth and accuracy. Having a high 1.6-GHz gain bandwidth product gives greater than 10-MHz signal bandwidths up to gains of 160 V/V 44 dB. The very low input bias current and capacitance supports this performance even for relatively high source impedances.

Broadband photodetector applications benefit from the low-voltage noise JFET inputs for the OPA657. The JFET input contributes virtually no current noise while for broadband applications, a low voltage noise is also required. The low 4.8 nV/√Hz input voltage noise provides exceptional input sensitivity for higher bandwidth applications. The example shown below gives a total equivalent input noise current of 1.8 pA/√Hz over a 10-MHz bandwidth.

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High Gain Bandwidth Product: 1.6 GHz

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High Bandwidth 275 MHz G = 10

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Slew Rate 700 V/µs G = 10, 1-V Step

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Available in High Grade With Improved DC

Specifications

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Operating Temperature Range: –40°C to 85°C

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Low-Input Offset Voltage: ±250 µV

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Low-Input Bias Current: 2 pA

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Low-Input Voltage Noise: 4.8 nV/√Hz

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High-Output Current: 70 mA

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Fast Overdrive Recovery