OEM Module for SEM Applications

The EBM20N5/24 powers E-Beam Columns in Thermionic Scanning Electron Microscopes providing acceleration, bias and filament sources in a single compact package. Spellman’s proprietary HV packaging and encapsulation technology gives dramatic improvements in size, cost and performance compared to other SEM power supply offerings. The EBM20N5/24 provides a highly regulated, low noise, ultra stable accelerator supply programmable from 0 to -20kV at 250uA. The EBM20 has floating bias and filament supplies referenced to the accelerator. Programming signals utilize differential analog inputs to minimize external noise and offset voltages effects. A ground referenced accelerator current monitor is provided. The EBM20 is arc and short circuit immune, along with over voltage and over current protection.

Typical applications:

• Scanning Electron Microscope

Specifications

^{(Ref. 128031-001 REV. B)}

SPECIFICAATIONS:

Input Voltage:

+24Vdc, ±5%, 1.5A maximum

High Voltage Outputs:

ACCELERATOR:

Voltage:

0V to -20kV full load with respect to ground

Current:

250μA maximum (including feedback current), continuous
from -500V to -20kV.

Current Trip Level:

275mA, ±10%. Trips off all outputs, reset by cycling
i nput power

Accuracy (voltage program):

±1% from -500V to -20kV

Load Regulation:

<±100ppm, 20μA to 250μA load change

Line Regulation:

<±100ppm for 10% line change

Ripple:

<20ppm p-p at -20kV, 250μA, maximum bias and filament output

Temperature Coefficient:

<100ppm/°C

Stability:

30ppm/3 minutes at 100μA load current after 1 hour warm up

Rise Time (switch ON):

<3 seconds (10% to 90%) with no overshoot

Fall Time (switch OFF):

<100 seconds (to <50 volts)

BIAS:

(Referenced to Accelerator)

Voltage:

0 to +1.5kV (max allowable output limited to 2kV)

Current:

150µA maximum

Accuracy (voltage program):

±3% of full scale

Line Regulation:

<±0.1% for 10% line change

Ripple:

<0.1% p-p

Temperature Coefficient:

<1000ppm/°C

Stability:

1%/10 minutes

Rise Time (switch ON):

<3 seconds (10% to 90%) with no overshoot

Fall Time (switch OFF):

<100 seconds (to <50 volts)

FILAMENT:

(center voltage WRT accelerator output)

Power:

0 to 12W

Load Resistance:

1.33Ω ±5%

Accuracy:

±3% of FS

Load Regulation:

<1% for 10% change in load resistance

Line Regulation:

<1% for 10% line voltage change

Ripple:

<0.1% p-p max

Temperature Coefficient:

<300ppm/°C

Stability:

100ppm/10 minutes

INTERFACE:

Input:

Analog control for accelerator, filament and bias

High Voltage Output:

Custom 3 pin receptacle and cable assembly

Temperature:

Operating: 5°C to +40°C

Storage: -20°C to +50°C

Humidity:

20% to 85% RH, non-condensing

Dimensions:

10.63˝H x 2.36˝W x 7.87˝D (270mm x 60mm x 200mm) excluding any mounting brackets

Weight:

<10 lbs. (4.5kg)

Regulatory Approvals:

The unit is designed to meet the requirements of EN61010, UL61010-1 and CAN CSA22.2 No. 61010. As the unit is a component within a system, it will not tested as a stand-alone unit to meet the EMC directive. The user will need to follow sensible EMC precautions in using the unit. RoHS compliant.

POWER INPUT CONNECTOR 3 PIN JST MODEL B 3PS-VH

CONTROL AND MONITORING CONNECTOR 10PIN JST MODEL S10B-EH

Tables & Diagrams

HV CABLE ASSEMBLY DETAILS

DIMENSIONS: in.[mm]

SIDE VIEW

TOP VIEW

FRONT VIEW

SIDE VIEW