InGaAs High Speed Photodetectors with AC Coupling
Single-Ended and Dual-Balanced
Wieserlabs offers high speed InGaAs photodetectors, in both single-ended and dual-balanced versions. All of them feature:
Please note: AC coupling in the detectors suppresses the DC light intensity preventing amplifier saturation even at high input levels. Such detectors are useful whenever the AC signal is relevant and the DC offset can be suppressed, e.g. for pulse measurements, swept source optical coherence tomography (SS-OCT) and certain noise measurements. However, for CW intensity monitoring, DC rather than AC-coupled photodiodes must be used, e.g. the WL-DPD200MA.
Dual-Balanced (i.e. differential) detectors feature two complementary light inputs. They are particularly well suited for applications where complementary signals are available, e.g. at the output of an interferometer. The dual-balanced detector amplifies the difference of the incoming light intensities thereby suppressing common-mode noise. Furthermore, for complementary signals, gain is increased by 6 dB (factor 2 in output voltage) compared to single-ended detection.
All Wieserlabs dual-balanced detectors can be used as single-ended ones simply by utilizing only one of the two inputs.
| Part | Detector | -3 dB BW | Gain 1550 nm | Coupling | Datasheet |
|---|---|---|---|---|---|
| BPD220MA | InGaAs | 220 MHz | 3500 V/W | AC (300 kHz) | download |
| BPD270MA5 | InGaAs | 270 MHz | 3500 V/W | AC (5 MHz) | download |
| BPD450MA | InGaAs | 450 MHz | 3500 V/W | AC (300 kHz) | download |
| BPD600MA | InGaAs | 600 MHz | 3500 V/W | AC (300 kHz) | download |
| BPD600MA-QUAD | InGaAs | 600 MHz | 5000 V/W | AC (30 kHz) | download |
| BPD1GA | InGaAs | 1 GHz | 3500 V/W | AC (300 kHz) | download |
Note: Other bandwidths and AC cutoff frequencies are available upon request. The trans-impedance gain can be increased up to 5000 V/Wopt..
Single-ended photodetectors have one single light input. They are useful whenever fast light modulations have to be detected, e.g. for pulse monitoring, propagation time measurements, offset locks, etc. Due to their high trans-impedance gain and low noise, these diodes are also well-suited for certain intensity noise measurements.
| Part | Detector | -3 dB BW | Gain 1550 nm | Coupling | Datasheet |
|---|---|---|---|---|---|
| WL-PD270MA | InGaAs | 270 MHz | 3000 V/W | AC (300 kHz) | download |
| WL-PD450MA | InGaAs | 450 MHz | 3000 V/W | AC (300 kHz) | download |
| WL-PD600MA | InGaAs | 600 MHz | 3000 V/W | AC (300 kHz) | download |
| WL-PD1GA | InGaAs | 1 GHz | 3000 V/W | AC (300 kHz) | download |
| WL-PD2GA | InGaAs | 2 GHz | 3000 V/W | AC (300 kHz) | download |