Ametek Signal Recovery 5402 User manual

Model 5402
Low-Noise Current
Preamplifier
Instruction Manual
1107364-A-MNL-B
Copyright © 2017 AMETEK ADVANCED MEASUREMENT TECHNOLOGY, INC

Trademarks
AMETEK® and the b® and alogos are registered trademarks of AMETEK, Inc.
Other product and company names mentioned are trademarks or trade names of their respective
companies.
Company Names
SIGNAL RECOVERY is part of Advanced Measurement Technology, Inc, a division of AMETEK,
Inc. It includes the businesses formerly trading as EG&G Princeton Applied Research, EG&G
Instruments (Signal Recovery), EG&G Signal Recovery and PerkinElmer Instruments (Signal
Recovery)

Table of Contents Table of Contents
i
General Safety Precautions................................................................................................................ii
Chapter One, Description
1.1 Description ....................................................................................................................................................... 1-1
1.2 Options ............................................................................................................................................................. 1-1
Chapter Two, Initial Checks
2.1 Introduction ...................................................................................................................................................... 2-1
2.2 Equipment Needed ........................................................................................................................................... 2-1
2.3 Procedure.......................................................................................................................................................... 2-1
Chapter Three, Operating Instructions
3.1 Introduction ...................................................................................................................................................... 3-1
3.2 Connectors & Controls..................................................................................................................................... 3-1
3.2.01 Power Switch & Indicator....................................................................................................................... 3-1
3.2.02 Charge Connector & Indicator ................................................................................................................ 3-1
3.2.03 Input Connector....................................................................................................................................... 3-1
3.2.04 Gain Button ............................................................................................................................................. 3-1
3.2.05 Low-pass Filter........................................................................................................................................ 3-2
3.2.06 Output Coupling...................................................................................................................................... 3-2
3.2.07 Output Connector .................................................................................................................................... 3-2
3.3 Operating the Model 5402................................................................................................................................ 3-2
3.3.01 Introduction ............................................................................................................................................. 3-2
3.3.02 Signal Gain & Output Voltage................................................................................................................ 3-2
3.3.03 Output Filtering....................................................................................................................................... 3-2
3.3.04 Battery Operation .................................................................................................................................... 3-2
3.3.05 Battery Charging ..................................................................................................................................... 3-3
3.3.06 Battery Maintenance................................................................................................................................ 3-3
Appendix A, Specifications
Appendix B, Model PS0112 External Power Supply
Appendix C, Model 5400/32 External Power Supply
Appendix D, Model 7210/50 Mounting Shelf
Warranty....................................................................................................................................... End of Manual

TABLE OF CONTENTS
ii
GENERAL SAFETY PRECAUTIONS
The equipment described in this manual has been designed in accordance with EN61010 "Safety
requirements for electrical equipment for measurement, control and laboratory use", and has been
supplied in a safe condition. To avoid injury to an operator or service technician the safety precautions
given below, and throughout the manual, must be strictly adhered to whenever the equipment is
operated, serviced or repaired. For specific safety details, please refer to the relevant sections within
the manual.
The equipment is intended solely for electronic measurement and should be used for no other purpose.
SIGNAL RECOVERY accepts no responsibility for accidents or damage resulting from any failure to
comply with these precautions.
AC Supply Voltage
Never operate the Model PS0112 or Model 5400/32 power supplies from a line voltage or frequency in
excess of that specified. Otherwise, the insulation of internal components may break down and cause
excessive leakage currents and POTENTIAL RISK OF ELECTRICAL SHOCK. The Model 5400/32
supply must be used with an IEC 60799 compliant (or other suitable accredited approval) mains supply
cord, rated for the correct voltage and power rating as detailed on the power supply case.
DC Supply Voltage
Never use a DC voltage greater than +9.5V to recharge the batteries in the Model 5402.
Fuses
The Model PS0112 power supply does not contain replaceable MAINS fuses, but the Model 5400/32
does. Refer to Appendix B for details of how to replace these.
Explosive Atmospheres
This equipment must NEVER BE OPERATED in a potentially explosive atmosphere. The equipment is
NOT designed for use in these conditions and could possibly cause an explosion.
Safety Symbols
The Model 5402 product contains no safety symbols (not required).
The PS0112 power supply contains the following safety symbols:
Symbol
Meaning
General safety hazard. CAUTION –Do not open PS0112 power supply case, risk of
electric shock. This product is not internally serviceable.
Electrical safety hazard. See above.

iii
Accessories and Ancillary Equipment
Only use accessories and ancillary equipment either delivered as part of the system or pre-approved
for use with the system directly by AMT. Use of unapproved accessories and ancillary equipment could
cause damage and potentially form an electrical hazard.
Notes and Cautions
For the guidance and protection of the user, Notes and Cautions appear throughout the manual. The
significance of these is as follows:
Notes highlight important information for the reader’s special attention.
Cautions guide the reader in avoiding damage to the equipment.
Avoid Unsafe Equipment
The equipment may be unsafe if any of the following statements apply:
Equipment shows visible damage.
Equipment has failed to perform an intended operation.
Equipment has been stored in unfavorable conditions.
Equipment has been subjected to severe physical stress.
If in any doubt as to the serviceability of the equipment, don't use it. Get it properly checked out by a
qualified service technician.
Live Conductors
The Model PS0112 or Model 5400/32 power supplies contain MAINS ‘LIVE’ conductors (internal). Their
cases should not be opened by under any circumstances, and they contain no user serviceable parts.
Equipment Modification
To avoid introducing safety hazards, never install non-standard parts in the equipment, or make any
unauthorized modification. To maintain safety, always return the equipment to your
SIGNAL RECOVERY service provider for service and repair.
European WEEE Directive
This product is subject to Directive 2002/96/EC of the European Parliament and the Council of the
European Union on waste electrical and electronic equipment (WEEE) and in jurisdictions adopting
that Directive, is marked as being put on the market after August 13, 2005, and should not be disposed
of as unsorted municipal waste. Please use your local WEEE collection facilities for the disposal of this
product and otherwise observe all applicable requirements.
FCC Notice
This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used
in accordance with this instruction manual, may cause harmful interference with radio communications.
Operation of this equipment in a residential area is likely to cause harmful interference, in which case
the user is required to correct the interference.

TABLE OF CONTENTS
iv
DECLARATION OF CONFORMITY
The directives covered by this declaration
2014/35/EU Low Voltage Equipment Directive
2014/30/EU Electromagnetic Compatibility Directive
Product(s)
Model 5402 Current Preamplifier
Basis on which conformity is being declared
The product(s) identified above comply with the requirements of the EU directives by
meeting the following standards:
BS EN61326-1:2013 Electrical equipment for measurement control and laboratory use -
EMC requirements –Class A.
BS EN61010-1:2010 Safety requirements for electrical equipment for measurement,
control and laboratory use.
Accordingly, the CE mark has been applied to this product.
Signed
For and on behalf of SIGNAL RECOVERY
Authority: Product Manager
Date: January 2017

Description Chapter 1
1-1
1.1 Description
The Model 5402 is a low noise current input preamplifier designed for use whenever
the signal source is a current source - for example, an electron multiplier, ion
collector, photo multiplier, or photodiode. The gain (transimpedance) is switch
selectable with six settings enabling the amplifier, on its most sensitive range, to
detect fractions of a picoamp without noise degradation.
The unit has a bandwidth of 100 kHz on its highest gain (1 GV/A) and greater than
5 MHz on its lowest gain (10 kV/A), while still maintaining low input current noise
ranging from 25 fA /Hz on the 1 GV/A range to 5 pA /Hz on the 10 kV/A range.
Figure 1-1, Model 5402 Low-Noise Current Preamplifier
1.2 Options
The Model 5402 is supplied complete with two internal lithium-ion rechargeable
batteries. The following options are available.
Model PS0112 Plug-in line power supply, capable of recharging the batteries in
one Model 5402. This unit is typically supplied as standard with
the Model 5402 unless multiple amplifiers are ordered as part of
a larger system, in which case an alternative supply, such as the
Model 5400/32, is included. See Appendix B for details of the
PS0112.
Model 5400/32 Benchtop line power supply for recharging the batteries of up to
32 Model 5402’s, typically used when the preamplifier is used
with the SIGNAL RECOVERY Model 7210 multi-channel
lock-in amplifier. See Appendix C for details of this unit.

Chapter 1, DESCRIPTION
1-2
Model 7210/50 Mounting Shelf. This allows up to 32 Model 5402’s to be
conveniently positioned together, on four shelves each
containing eight preamplifiers. See Appendix D for details of
this shelf.

Initial Checks Chapter 2
2-1
2.1 Introduction
The following procedure is provided to facilitate initial performance checking of the
Model 5402. In general, the procedure should be performed after inspecting the unit
for shipping damage (any noted to be reported to the carrier and to
SIGNAL RECOVERY), but before using it experimentally. Should any difficulty be
encountered in carrying out these checks, contact the factory or one of its
representatives.
2.2 Equipment Needed
1) General purpose laboratory oscilloscope.
2) Signal generator capable of providing a 1 V, 100 mV and 10 mV pk-pk sine
wave at 1 kHz, with a variable DC output offset facility of up to ±1.0 V
3) Two test modules, consisting of screened enclosures fitted with male and female
BNC connectors. One module should have a 10 kand the other a 10 Mlow-
capacitance resistor connected between the BNC’s inner connecting pins. The
outer shield or ground terminals of these connectors should be connected
together.
2.3 Procedure
1) Slide the POWER switch on the input panel to the ON position (i.e. closest to
the input BNC connector). The adjacent red LED and one of the GAIN LEDs
should light, indicating that the internal batteries are sufficiently charged.
Units are shipped with their batteries typically at 50% of their full charge level,
so will normally operate without first being charged. If, however, the red power
LED doesn’t light, refer to section 3.4 for a discussion of how to recharge the
batteries.
2) Set the OUTPUT switch to AC
3) Set the LOWPASS filter switch to 100 kHz
4) Press the GAIN button repeatedly until the 10k setting is selected, as indicated
by the LED adjacent to it being lit.
5) Connect the oscilloscope input to the 5402’s output BNC connector.
6) Set the signal generator to 1 kHz, 1 V pk-pk, and connect it via the 10 kBNC
test module to the INPUT BNC connector. Use the oscilloscope to monitor the
signal generator amplitude settings so as to obtain consistency between input
settings and output readings.
7) Monitor the output; the output level should be 1.0 ± 0.1 V pk-pk.
8) Set the OUTPUT switch to DC.
9) Reduce the signal generator amplitude to 100 ± 10 mV pk-pk, and apply a 1 V
DC offset to its output. Apply this to the Model 5402 via the 10 kBNC test

Chapter 2, INITIAL CHECKS
2-2
module and verify that the output level is a 100 ± 10 mV pk-pk AC signal
superimposed on a 1.0 ± 0.1 V DC level.
10) Remove the DC offset from the signal generator output and set the OUTPUT
switch back to AC.
11) Press the GAIN button repeatedly until the 100k setting is selected and monitor
the output; the output level should be 1.0 ± 0.1 V pk-pk
12) Set the signal generator to 1 kHz, 10 mV pk-pk. Then press the GAIN button
repeatedly until the 1M setting is selected and monitor the output; the output
level should be 1.0 ± 0.1 V pk-pk
13) Remove the 10 kBNC test module and replace it with the 10 MBNC test
module.
14) Set the signal generator to 1 kHz, 1 V pk-pk. Then press the GAIN button
repeatedly until the 10M setting is selected and monitor the output; the output
level should be 1.0 ± 0.1 V pk-pk
15) Set the signal generator to 1 kHz, 100 mV pk-pk. Then press the GAIN button
repeatedly until the 100M setting is selected and monitor the output; the output
level should be 1.0 ± 0.1 V pk-pk. In some cases, parasitic capacitance across the
10 Mtest module resistor may give a higher output level on this test and step
16) below; if this occurs, reduce the test frequency to 90 Hz.
16) Set the signal generator to 1 kHz, 10 mV pk-pk. Then press the GAIN button
repeatedly until the 1G setting is selected and monitor the output; the output
level should be 1.0 ± 0.1 V pk-pk
17) Return the power switch to the OFF position.
This completes the initial checks. If the amplifier performed as indicated, one can be
reasonably sure that it has arrived in good working order and is functioning properly.

Operating Instructions Chapter 3
3-1
3.1 Introduction
The Model 5402 has been designed to be extremely easy to setup and use. It is
powered from its internal rechargeable batteries, which can help avoid ground loops
and reduce the overall system noise. A 9 V DC power supply is used to recharge the
batteries.
In operation, the signal to be amplified is applied to the input BNC connector, and
the resulting output is taken directly to the input of the lock-in amplifier, ADC
module, oscilloscope, or other instrument with which the 5402 is to be used.
3.2 Connectors & Controls
3.2.01 Power Switch & Indicator
The power switch, which is mounted on the end plate with the INPUT BNC
connector, is a slide switch with two positions. When the actuator is moved closest
to the connector, the amplifier is turned on; when moved to the other position it is
turned off. The red LED next to the switch lights when the unit is turned on and
either the batteries are sufficiently charged or it is connected to an external power
source.
If the LED does not light when the switch is turned on the batteries should be
recharged by connecting a suitable power supply to the CHARGE connector.
3.2.02 Charge Connector & Indicator
The 1.3 mm power socket marked CHARGE is used to connect the Model 5402 to
an external 9 V DC power source to recharge the internal batteries. When such a
source is present and the batteries are charging, the adjacent red LED is lit. The LED
extinguishes when the batteries are fully charged. The center pin of the connector is
the positive connection; the outer barrel connection is the negative connection.
3.2.03 Input Connector
The Model 5402’s INPUT connector is connected to the chassis 0 V ground and DC
coupled. The current source should be connected to the input by means of a low
noise coaxial cable and BNC connector. Since cable capacitance can affect the
frequency response, the cable length should be kept as short as possible, particularly
on the higher gain settings.
3.2.04 Gain Button
The GAIN button is used to select the overall gain (transimpedance) of the amplifier
between six different settings, providing a trade-off between sensitivity, noise,
bandwidth and DC overload capability. The gain is switchable in decade steps from
10K to 1G V/A, with the present setting being indicated by one of six LEDs being
lit. Each press of the button increases the gain by one step; when the gain is at 1G
the next press of the button sets it to 10k
The present gain setting is retained when the unit is turned off, avoiding the need to
reset it each time the unit is turned back on.

Chapter 3, OPERATING INSTRUCTIONS
3-2
3.2.05 Low-pass Filter
The amplifier includes an output low-pass filter with three settings of 100 kHz,
1 MHz, or 10 MHz, as selected by the LOWPASS slide switch. The filter has a roll-
off of 18 dB/octave with corner frequencies of 100 kHz ±15 kHz, 1 MHz ±150 kHz,
or 10MHz±1.5 MHz as indicated by the 100k, 1M, and 10M switch settings
respectively.
3.2.06 Output Coupling
The output signal can be AC or DC coupled, as selected by the OUTPUT slide
switch. When AC coupled the low-frequency cut off frequency is 0.1 Hz.
Typically, the amplifier output coupling should be set to AC to optimize battery life,
unless a DC coupled output is specifically required. Also when applying a 50 
output load to the amplifier (or any load less than 10 k), the output coupling should
only be set to AC. Using DC output coupling with a 50 output load will cause the
battery charge levels to become imbalanced, shortening their useful life.
3.2.07 Output Connector
The amplified signal is connected to the output BNC connector. The output
impedance is 50 with short-circuit protection.
3.3 Operating the Model 5402
3.3.01 Introduction
The amplifier is powered from the self-contained batteries, which can be recharged
from an external 9 V DC power source, such as the SIGNAL RECOVERY Model
PS0112 (see Appendix B). The signal to be amplified is applied to the INPUT
connector, and he amplified signal is available at the OUTPUT connector.
3.3.02 Signal Gain & Output Voltage
The gain selector accurately sets the gain to the indicated level. The output is
guaranteed not to clip for output voltages of up to a minimum of ±2.5 V into a high
impedance load, but with fully charged batteries larger output voltages of up to
±4.0 V are possible.
3.3.03 Output Filtering
If measuring very low frequency signals (for example below about 10 Hz), the
OUTPUT coupling must be set to DC. At frequencies above 10 Hz when rejection
of any DC signal on the output is required, the switch can be set to AC.
If using the higher gain settings (10M and above) and if the signal frequency is low
enough, then setting the LOWPASS filter to 1M or 100k can give a useful reduction
in the overall level of system noise. This filtering can be useful when using gains of
100M or 1G, which by their nature will produce a noisier output. If, however, the
widest bandwidth is required then set it to 10M.
3.3.04 Battery Operation
The internal batteries will power the Model 5402 for up to 48 hours, depending on

Chapter 3, OPERATING INSTRUCTIONS
3-3
the amplifier output level, load, and general battery health. Under typical conditions,
operating time will exceed one day. Battery powered operation gives the lowest
possible noise and eliminates any problems that might occur due to ground loops.
When the batteries become discharged the amplifier automatically switches off.
3.3.05 Battery Charging
The batteries are recharged, which will take around 3.5 hours from a fully discharged
state, when a 9 V DC external power supply (such as the PS0112 –see Appendix B)
is connected to the CHARGE connector. The batteries can be charged with the unit
switched on or off, although slightly increased charge times should be expected with
the unit switched on. The connection is via a 1.3 mm DC plug connector. The
charging circuit is automatic and prevents the batteries from being overcharged.
While charging, the red LED next to the CHARGE connector is lit.
If DC power is permanently applied to the CHARGE connector the batteries will
cycle between charging and discharging modes, with the amplifier still being
powered from the batteries. Although no harm will be done by this cycling, it is
important to note that it could introduce unwanted interference to the signal. Hence
for best performance it is recommended that DC power only be applied to fully
recharge the batteries and that critical measurements are only made when the
amplifier disconnected from the charging supply.
3.3.06 Battery Maintenance
The lithium-ion batteries used in the Model 5402 should last for several years in
normal use. However, their lifetime can be shortened for several reasons, such as:
If they are allowed to become too discharged (for example if they are not fully
recharged at least once per year).
If they are routinely operated with a large dc output offset into a 50 output
load.
When they do eventually need replacement, as indicated by severely shortened
operating time between charges, please contact SIGNAL RECOVERY for further
advice.
Warning: The batteries include protection circuitry and for continued safe
operation must only be replaced with approved parts.
However, in the case whereby the amplifier has been routinely operated with a large
dc output offset into a 50 output load, it may be possible to recondition the
batteries into a healthy working state. Follow the procedure below:
1) Connect the 9Vdc charger to the amplifier, switch the charger on, and allow the
amplifier to charge until the charge LED extinguishes. For batteries that require
reconditioning, the charge cycle time will be much shorter than the typical 3.5
hours.
2) Once the charge cycle is complete, remove the charger and switch the amplifier
on. Allow the amplifier to completely discharge with nothing connected to its
input or output.
3) With no connections made, the 5402 will slowly re-balance the charge levels in
each battery automatically. After a single discharge cycle, the batteries should be
fairly well reconditioned. However, it may be necessary to repeat steps 1 and 2 a

Chapter 3, OPERATING INSTRUCTIONS
3-4
second or even a third time to complete the process.

Specifications Appendix A
A-1
General
DC coupled current to voltage amplifier with adjustable gain and a maximum
frequency response extending from DC to 5 MHz. Single-ended grounded input and
single-ended DC or AC coupled output via BNC connectors.
Battery powered from internal lithium-ion rechargeable batteries or external DC
power supply.
Input
Mode Single-ended
Coupling DC
Maximum safe input voltage ±20 V DC
Input Bias Current < 1 pA
Input Referred Voltage Noise 2.5nV/Hz typical
Input Referred Current Noise See Table A-1
Gain & Frequency Response
Gain Switch selectable (6 settings)
1G, 100M, 10M, 1M, 100k, 10k V/A
Accuracy ± 0.5 dB
Flatness in pass-band ± 0.5 dB
Frequency Response See Table A-1
Gain
Bandwidth (–3dB)
with Cin = 10 pF
Bandwidth (–3dB)
with Cin = 1 nF
Input Referred
Current Noise
(typical)
10K
> 5 MHz
> 500 kHz
5 pA/Hz
100K
> 2 MHz
> 200 kHz
1 pA/Hz
1M
> 800 kHz
> 100 kHz
500 fA/Hz
10M
> 450 kHz
> 80 kHz
100 fA/Hz
100M
> 250 kHz
> 25 kHz
50 fA/Hz
1G
> 100 kHz
> 20 kHz
25 fA/Hz
Table A-1, Typical Frequency Response
Output Filters
Output Coupling (high-pass) When set to DC, amplifier is DC coupled.
When set to AC, low-frequency cut off is 0.1 Hz
Output Filter (low-pass) Low pass Butterworth filter with 18 dB/octave
roll-off filter reduces overall noise, especially
when working at high gains, if full bandwidth
is not required.
Settings:
10 MHz Full bandwidth
1 MHz Cut off frequency 1 MHz ± 150 kHz
100 kHz Cut off frequency 100 kHz ± 15 kHz

Appendix A, SPECIFICATIONS
A-2
Output
Impedance 50 
Max voltage swing > 5 V pk-pk
Polarity Current flowing into the input produces a
positive output voltage
Protection Output is short-circuit protected
Power
Internal Rechargeable lithium ion batteries provide
up to 48 hours of use. Batteries recharge
automatically when DC power is connected
Recharge time is maximum of 4 hours.
External 9 V DC @ 350 mA max
Connector 1.3 mm DC power socket, inner pin positive,
outer barrel negative
General
Dimensions
Excluding connectors 3½" wide 1¼" deep 2¾" high
(85 mm wide 31 mm deep 71 mm high)
Including connectors 4½" wide 1¼" deep 2¾" high
(114 mm wide 31 mm deep 71 mm high)
Weight 7.5 oz. (210 g) excluding optional power supply
Operating Location Indoor use only
Altitude Up to 2000 m
Pollution Degree Level 2
Operating Temperature 5° to 40°C
Storage Temperature –25° to 70°C
IP Rating N/A
Max. Humidity 80% for temperatures up to 31°C, decreasing
linearly to 50% relative humidity at 40°C
Max. Operating Time Designed for continuous operation

Power Supply Unit
(Model PS0112) Appendix B
B-1
Figure B-1, Model PS0112 External Power Supply
The Model PS0112 power supply consists of a rectangular unit with integral cable
terminated in a 1.3 mm DC power plug, and four interchangeable pin headers to suit
different styles of line output sockets. The DC power plug should be connected to
the CHARGE connector on the Model 5402.
Select the pin header to match the local style of socket, and slide it onto the power
unit until it clicks into place. Figure B-2 shows the assembly when fitted with a US
style pin header.
Figure B-2, Model PS0112 External Power Supply with US Plug Fitted
WARNING: The pin headers must never be plugged into a power socket when they
are not clipped onto the power unit. The unused pin headers should be safely
disposed of.

Appendix B, POWER SUPPLY UNIT (MODEL PS0112)
B-2

Power Supply Unit
(Model 5400/32) Appendix C
C-1
Figure C-1, Model 5400/32 External Power Supply –Front Panel
Figure C-2, Model 5400/32 External Power Supply –Rear Panel
The Model 5400/32 power supply is designed to allow the batteries in up to 32
Model 5402 or similar preamplifiers to be recharged from a single line supply. It
consists of a benchtop console fitted with 32 1.3 mm DC power output sockets on
the front panel and an IEC line power input connector and power switch on the rear
panel. It is supplied with an IEC input cable suitable for the country of use.
The unit uses forced-air cooling so must be positioned with at least 4″of clear space
at the back.
Fuses
The Model 5400/32 is fitted with two 20 mm fuses. The required ratings are as
follows:
Supply Voltage Rating
100 –120 V AC 4.0 A slow-blow (T), 250 V
200 –260 V AC 2.0 A slow-blow (T), 250 V
Note that it is not necessary to make any adjustment to set the line input voltage.
To check, and if necessary change, the fuses, proceed as follows:

Appendix C, POWER SUPPLY UNIT (MODEL 5400/32)
C-2
1) Remove the IEC input power connector, if plugged in.
2) Use a small flat bladed screwdriver to withdraw the fuse drawer, as shown in
figure C-3
Figure C-3, Model 5400/32 External Power Supply –Input Fuse Drawer
3) The fuses can now be inspected and changed if necessary.
4) Reinsert the fuse drawer into the assembly.
DC Power Cable
The CHARGE connector on each Model 5402 should be connected to one of the
power output sockets on the front panel of the 5400/32 using a power cable, part
number 1107080, shown below in figure C-4. It does not matter which end of the
cable is plugged into the 5402 or 5400/32.
Figure C-4, DC Power Cable