R
AMP
TEK
Single In-line Package (SIP)
The A250F/NF is a high density version of the Amptek A250 Charge Sensitive Preamplifier.
The input FET is not included and must be added externally.
+Vs
PIN聽5
R
External
FET
GD
S
1K
A250F/NF
PIN CONFIGURATION
Pi n 1
PIN聽6
OUTPUT
A250F/NF
PIN聽2
PIN聽1
0.25聽pF
)
F e e d b a ck.
Must be connected to
the Gate of the FET.
Input.
Must be connected to
the Drain of the FET.
Ground & Case
-Vs (-6 V Typical)
+Vs (+6 V Typical)
Output
)
DETECTOR
INPUT
Pi n 2
PIN聽4
1聽G
W
Pi n 3
Pi n 4
Pi n 5
PIN聽3
GROUND
&聽CASE
-Vs
Pi n 6
NOTES
1. The internal feedback resistor R
f
= 1 GW.
2. The internal feedback capacitor C
f
= 0.25 pF
Sensitivity (gain) = 175 mV//MeV (Si)
4 V/pC
0.64
mV/electron
3. For lower sensitivity applications, C
f
can be increased externally.
4. The external 1 kW resistor from Pin 2 to Pin 5 provides the FET with a drain current of I
DS
= 2.75 ma.
I
DS
can be increased by reducing R < 1 kW.
Please refer to the A250 specifications for further information.
A250F/NF
A250F/NF
MECHANICAL DIMENSIONS
6 DE ANGELO DRIVE, BEDFORD, MA 01730-2204 USA
TEL: +1 (781) 275-2242 FAX: +1 (781) 275-3470 email: sales@amptek.com www.amptek.com
AMPTEK
INC.
1
