TOF detector with a built-in voltage divider, mounted on a printed circuit board, is designed for detection of charged particle fluxes as part of a mass spectrometer

Detectors for time-of-flight mass spectrometers must have a high-speed response without “damped” oscillations (TOF detectors) and must detect ions with high efficiency. Therefore, MCP detectors, which have high ion sensitivity, sub-nanosecond response time and are compact, are mainly used as such detectors.
The board used to assemble the MCP detector contains the detector voltage divider, power supply circuit components, and a coaxial connector for signal acquisition. Assembly of the detector with the board allows to reduce the influence of spurious inductances and capacitances, as a result the output pulse of the MCP-detector acquires a classical waveform without “damped” oscillations and has a short width (less than 1 ns). The compact design, with 2 inputs for voltage supply and a coaxial connector for signal acquisition, is more adaptable to the application and allows easy installation and replacement of the detector when needed.




Specification
Basic parameters
Parameter, unit | Value | |
---|---|---|
min | max | |
MCP active area diameter, mm | 26 | |
Supply voltage at 1×107 gain, V | 2400 | |
Single electron pulse height resolution, % | 130 | |
Dark count rate density, count/sec×cm2 | 2 | |
Average pulse width (FWHM), ns | 0.85 | |
Pulse leading edge rise time, ns | 0.5 | |
Product consumption current at supply voltage, μA | 250 |
Typical output waveform

The detector electrical connection diagram

R1 = 10 MΩ;
R2 = R3 = 1 MΩ;
С1 = С2 = 470 pF;
Usupply = -2.4 kV, max
1 – control electrode;
2 – MCP unit;
3 – anode
General view, overall, setting and mounting dimensions of MCP detector with 25 mm active area diameter



Lead designation | |
---|---|
1 | Supply voltage –2400 V, max |
2. 3 | Package |
SMA | Signal output |
А | Anode |