AD 5B45-01

Isolated, Frequency Input
5B45 / 5B46
Isolated Frequency Input.
Amplifies, Protects, Filters, and Isolates Analog Input.
Generates an output of 0 to +5V proportional to input
Model 5B45 accepts full-scale inputs from 500 Hz to 20 kHz.
Model 5B46 accepts full-scale input from20 Khz to 275 kHz.
Module circuitry can withstand 240v rms at the input screwterminals.
All 5B45 & 5B46 series modules are mix-and-match and Hot
Figure 1. 5B45 & 5B46 Functional Block Diagram
Industrial signal conditioning
Industrial signal isolation
Industrial signal filtering
The 5B Series represents an innovative generation of low cost,
high performance plug-in signal conditioners. Designed for
industrial applications, these modules incorporate highly
reliable transformer-based isolation and automated surfacemount manufacturing technology. They are compact,
economical components whose performance exceeds that
available from more expensive devices. Combining 1500 V rms
continuous isolation, +0.05% calibrated accuracy, small size and
low cost, the 5B Series is an attractive alternative to expensive
signal conditioners and in-house designs
All modules are potted and identical in pin-out and size (2.27” x
2.32” x 0.595”). They can be mixed and matched, permitting
users to address their exact needs, and may be “hot swapped
without disturbing field wiring or power. The isolated input
modules provide 0 to +5V or +5V outputs and accept J, K, T, E,
R, S, N, or B type thermocouples.
These modules feature complete signal conditioning functions
including 240 V rms input protection, filtering, chopper
stabilized low drift +1 uV/oC amplification, 1500 V rms
isolation, and sensor excitation when required.
All modules feature excellent common mode rejection and
meet industrial transient surge withstand specifications.
There are also a number of backplanes and mounting sockets
which provide a complete signal conditioning solution for end
users. Each backplane incorporates screw terminals for field
wiring inputs and outputs and cold junction sensors for
thermocouple applications.
These signal conditioners are designed to provide an easy and
convenient solution to signal conditioning problems of both
designers and end users in measurement and control
applications. Typical uses include microcomputer-based
measurement systems, standard data acquisition systems,
programmable controllers, analog recorders and dedicated
control systems. The 5 B series modules are ideally suited to
applications where monitoring and control of temperature,
pressure, flow, rotation and other analog signals are required.
The 5B Series modules and backplanes are approved by Factory
Mutual (FM) and the 5B Series modules are approved by the
Canadian Standards Association (CSA) for use in Class 1,
Division 2, Groups A, B, C, and D locations. These approvals
certify that the 5B Series is suitable for use in locations where a
hazardous concentration of flammable gas may exist only under
fault conditions of operation. Equipment of this category is
called “nonincendive” and they need no special enclosures or
other physical safeguards.
The 5B series modules and backplanes have been tested and
passed the stringent heavy industrial requirements of the
European Union’s electromagnetic compatibility (ENC)
directive – EN50082-1 and EN50081-2. When used according
to installation directions (refer to 5B series User Manual), any
errors caused by EMI/RFI interference will be less than 0.1% of
the full scale 5B measurement range for field strengths up to 10
V/M and frequencies up to 1 GHz.
Rev. 0
Information furnished by Analog Devices is believed to be accurate and reliable.
However, no responsibility is assumed by Analog Devices for its use, nor for any
infringements of patents or other rights of third parties that may result from its use.
Specifications subject to change without notice. No license is granted by implication
or otherwise under any patent or patent rights of Analog Devices. Trademarks and
registered trademarks are the property of their respective companies.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.326.8703
© 2004 Analog Devices, Inc. All rights reserved.
5B45 / 5B46
to provide a low-noise, low-impedance output signal that is
accurately proportional to input frequency.
The 5B45 and 5B46 are single-channel isolated frequency input
modules that produce a 0 to +5V output proportional to input
frequency. Model 5B45 accepts full-scale inputs ranging from
500 Hz to 20 kHz. Model 5B46 accepts full-scale inputs ranging
from 20 kHz to 275 kHz. Both models allow the user to set the
threshold to either 0 V (for zero crossing signals) or +1.4 V (for
positive level signals), and the hysteresis to either +25 mV or
+400 mV (all input types).
Simple Setup and Versatile Choices – Setting the threshold
and hysteresis values is a simple matter of externally wiring to
the backplane screw terminals. The threshold for measuring a
zero-crossing voltage waveform (such as sine waves) is set to 0
volts by connecting the input signal across screw-terminals 4
and 3. The threshold for a positive level signal (such as a TTL or
pulse train waveform) is set at +1.4V by connecting the input
signal across terminals 3 and 2. Hysteresis for both input signal
types is set at +400 mV but can be changed to +25 mV by
adding a jumper between screw terminals 1 and 4. Response
time is a function of a modules rated input frequency range.
(See the 5B45 and 5B46 Model Table).
The 5B45 and 5B46 protect the computer side from field-side
over-voltage faults. All models withstand 240 V rms at their
input terminals without damage, thereby shielding computerside circuitry from field-side over-voltage conditions. In
addition, all 5B45 and 5B46 models are mix-and match and hotswappable, so can be inserted or removed from any socket in
the same backplane without disrupting system power.
The input circuit is fully floating and isolated from the output
and power commons. In addition, the output section acts as a
third floating port towards eliminating possible problems from
ground loops and power supply noise. The output common
must be held within +3V of power common.
Inside 5B45 & 5B46 Modules – The 5B45/46 internal circuitry
compares the input signal to the user-selected threshold (VT)
and hysteresis (VH). Signals of virtually any wave shape that
exceed the combined threshold and hystersis levels (VT
+VH)will trigger a comparator at a rate determined by the input
frequency. The comparator output is then transmitted across a
proprietary transformer-coupled isolation barrier and
converted to a high-level analog signal. This signal is then
filtered by a multi-pole low pass Butterworth filter and buffered
A series output switch eliminates the need for external
multiplexing in many applications. The switch is turned on by
an active-low enable input. If the switch is to be on at all times,
the enable-input should be grounded to power common as it is
on the 5B01 and 5B08 backplanes..
Figure 2
Rev. 0 | Page 2 of 8
5B45 / 5B46
5B45 and 5B46 Models Available
Input Range
Output Range
Rise/Fall Time
Step Response
0 Hz to 500 Hz
0 V to +5 V
80 ms
150 ms
0 Hz to 1 kHz
0 V to +5 V
60 ms
140 ms
0 Hz to 2.5 kHz
0 V to +5 V
50 ms
130 ms
0 Hz to 5 kHz
0 V to +5 V
50 ms
130 ms
0 Hz to 10 kHz
0 V to +5 V
50 ms
130 ms
Input Range
Output Range
Rise/Fall Time
Step Response
0 Hz to 25 kHz
0 V to +5 V
15 ms
44 ms
0 Hz to 50 kHz
0 V to +5 V
7 ms
22 ms
0 Hz to 100 kHz
0 V to +5 V
4 ms
12 ms
0 Hz to 250 kHz
0 V to +5 V
4 ms
9 ms
* Custom Input/Output ranges are available. Refer to configuration guide.
5B45 and 5B46 Specifications
Model 5B45
Model 5B46
Frequency Input
Standard Ranges
Refer to Model Table
Refer to Model Table
Custom Ranges
500 Hz span, min.; 20 kHz span, max.
20 kHz span, min.; 275 kHz span, max.
20% of Span
Voltage Range
70 mV rms min. 240 V rms max.
Sine, Square, Triangle, Pulse Train
2 µs min.
Zero Crossing or TTL (+1.4 V)
TTL Input, Low (-40°C to +85°C)
0.8 V max.
TTL Input, High (-40°C to +85°C)
2.0 V min.
±25 mV or ±400 mV
Pulse Width (Pulse Train Inputs)
Threshold Options
Hysteresis Options
Output Ranges (RL > 50 k Ω)
-5 V to +5 V or 0 V to +5 V
Initial @ +25°C
±0.05% Span (±0.1% Span, max.)
±0.005% Span (±0.015% Span, max.)
Output Offset vs. Temperature
±20 µV/°C
Gain vs. Temperature
±20 ppm/°C
Input Bias Current, Vin < 5 V peak-peak
100 µA
Input Impedance
Small Signal, Vin < 5 V peak-peak
Large Signal, Vin > 5 V peak-peak
40 k Ω || 330 pF
Rev. 0 | Page 3 of 8
5B45 / 5B46
Power Off
40 k Ω || 330 pF
Output, 100 kHz Bandwidth
0.7 mV peak-peak
Output, 5 MHz Bandwidth
7 mV peak-peak
Output Ripple
10 mV peak-peak @ (10% Fspan +F-full scale)
Bandwidth, -3 dB
10 Hz
190 Hz
Output Step Response Time
Refer to Model Table
Common-Mode Voltage (CMV)
Input-to-Output, Continuous
1500 V rms, maximum
Output-to-Power, Continuous3
±3 V, maximum
ANSI/IEEE C37.90.1-1989
Common-Mode Rejection (CMR)
1 k Ω Source Imbalance, 50/60 Hz
120 dB
Input Protection
240 V rms, maximum
ANSI/IEEE C37.90.1-1989
Output Resistance
50 Ω
Voltage Output Protection
Continuous Short to Ground
Output Selection Time
6 µs @ Cload = 0 to 2,000 pF
Output Enable Control
Max Logic "0"
+1.0 V
Min Logic "1"
+2.5 V
Max Logic "1"
+36 V
Input Current "0"
0.4 mA
Power Supply Voltage
+5 V ±5%
Power Supply Current
70 mA
Power Supply Sensitivity, RTO
±0.005% of Span/% of Vs
Mechanical Dimensions
2.275" x 2.375" x 0.595"
(57.8 mm x 59.1 mm x 15.1 mm)
Temperature Range
Rated Performance
-40°C to +85°C
Operating Performance
-40°C to +85°C
-40°C to +85°C
Relative Humidity
0 to 93% @ +40°C non-condensing
RFI Susceptibility
±0.5% Span error @ 400 MHz, 5 Watt, 3 ft
* Specifications same as model 5B45.
Jumper selectable. Refer to Field Connection diagram.
Includes the combined effects of repeatability, hysteresis, and nonlinearity. Loads heavier than 50 k Ω will degrade nonlinearity and gain temperature coefficient.
The Output Common must be kept within ±3 V of Power Common.
Specifications subject to change without notice.
Rev. 0 | Page 4 of 8
5B45 / 5B46
Figure 3 5B45 & 5B46 Input Field Connections
Table 1. Pin Function Descriptions—
Pin No.
Figure 4 . Model 5B Series Module, with pin-out assignments.
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human
body and test equipment and can discharge without detection. Although this product features proprietary ESD
protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges.
Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality.
Rev. 0 | Page 5 of 8
5B45 / 5B46
Figure 5. Outline Dimensions
Rev. 0 | Page 6 of 8
5B45 / 5B46
Rev. 0 | Page 7 of 8
5B45 / 5B46
© 2004 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective companies.
Rev. 0 | Page 8 of 8