OPTILAB BPR EVB User manual

BPR EVB User’s Manual
Balanced Photo Receiver Evaluation Board
Caution: The user must read this manual before operating the BPR EVB.
Operations other than those described in this manual may result in personal
injury and damage to the unit.
Ver. 2.1
January 17th, 2022

BPR EVB User’s Manual ii
Optilab, LLC
600 E. Camelback Road, Phoenix, AZ 85012
Phone: [phone], Fax: [phone], Email: [e-mail]
Revision History
Version
Date
Summary
1.0
8/18/15
Manual introduced.
2.0
3/16/16
PCB Rev 2. Bypass caps are incorporated.
2.1
1/17/2022
Logo and Format Update
Copyright ©2015 by Optilab, LLC.
All rights reserved.
This document is copyrighted property of Optilab, LLC. It may not be used in whole or in
part for manufacture, sale, or design of items without the written permission of Optilab,
LLC.
Information herein is preliminary and subject to change without any notices.

BPR EVB User’s Manual iii
Optilab, LLC
600 E. Camelback Road, Phoenix, AZ 85012
Phone: [phone], Fax: [phone], Email: [e-mail]
Table of Contents
1. BPR Configuration...............................................................................................................................1
1.2 Bandwidth Adjustment ............................................................................................................2
1.3 Operation Mode...........................................................................................................................2
2. Evaluation Board.................................................................................................................................3
2.1 Device Mounting Procedure ..................................................................................................3
2.2 Schematic of Evaluation Board.............................................................................................4
2.3 Default Setting ..............................................................................................................................4
2.3.1 How to use manual gain control (MGC) mode.....................................................5
2.3.2 How to use automatic gain control (AGC) mode ................................................6
2.4 Operation Instruction ...............................................................................................................6

BPR EVB User’s Manual 1 of 7
Optilab, LLC
600 E. Camelback Road, Phoenix, AZ 85012
Phone: [phone], Fax: [phone], Email: [e-mail]
1. BPR Configuration
1.1 Butterfly Package Pin-out Diagram and Description
BPR is packaged inside a 14-pin butterfly package. For your reference, we have included
a table for the pin-out diagram for the BPR.
Figure 1 Butterfly Package Pin-out Diagram
Table 1. BPR Pin Out Configuration
Pin 1, 5, 10, 14
Vcc
+2.8 to 3.3 V, abs max current is 93 mA
Pin 2
BWM
Bandwidth Adjust, Sign.
Pin 3
BWA
Bandwidth Adjust, Magnitude.
Pin 4
OA
Output Amplitude Adjust. 0-3.3 VDC
adjustment for AGC mode.
Pin 6, 9
GND
Ground
Pin 7
VPD1
PD1 Cathode Connection.
Pin 8
VPD2
PD2 Cathode Connection.
Pin 11
GC
Gain Control. 0-3.3 VDC adjustment for
MGC mode. Set to FLT in AGC mode.
Pin 12
MC
Mode Control. GND: MGC mode; FLT:
AGC mode; Vcc: Shutdown.
Pin 13
PKD
Peak Detector Output
OUTP
Positive RF Output, DC coupled out
OUTN
Negative RF Output, DC coupled out
BPR

Optilab, LLC
600 E. Camelback Road, Phoenix, AZ 85012
Phone: [phone], Fax: [phone], Email: [e-mail]
1.2 Bandwidth Adjustment
BPR offers a bandwidth adjustment feature that allows users to optimize optical receiver
performance for different applications. BPR bandwidth can be adjusted as needed. The
table below gives the bandwidth based on BWM and BWA settings when both PDs are
reversed biased at 3.3V.
Table 2. Bandwidth Setting Lookup Table
Setting
BWM
BWA
Min. Bandwidth (GHz)
1
GND
Vcc
13
2
GND
FLT
15
3
GND
GND
16
4
FLT
FLT
18
5
Vcc
GND
20
6
Vcc
FLT
20.5
7
Vcc
Vcc
21
In default setting on the evaluation board, both BWM and BWA are preset to Vcc to
achieve the largest bandwidth. If a bandwidth smaller than 13 GHz is desired, the user
can lower VPD1 and VPD2 to further reduce the overall bandwidth of BPR.
1.3 Operation Mode
BPR integrates a single, differential linear trans-impedance / variable-gain amplifier
(TIA/VGA). The TIA offers two gain control modes: manual gain control and automatic
gain control. In manual mode, MC pin should be connected to GND. The gain is
adjustable from 50 Ω to 5000 Ω differential by adjusting the GC level. When MC is
floating, BPR is operated in automatic gain control (AGC) mode. In AGC mode, the gain
is automatically adjusted to deliver a constant output voltage. The output amplitude is
adjustable over 20 dB dynamic range by adjusting the level of OA.
Table 3. Operation Mode Selection
Operation Mode
MC Setting (Pin 12)
Amplitude / Gain Adjustment
Manual Gain Control
GND
GC (Pin 11), 0 ~ 3.3V
Auto Gain Control
Floating
OA (Pin 4), 0 ~ 3.3 V
Shut Down
Vcc
N.A.
The default setting on the evaluation board is MGC. GC is preset to Vcc to maximize the
TIA gain.

Optilab, LLC
600 E. Camelback Road, Phoenix, AZ 85012
Phone: [phone], Fax: [phone], Email: [e-mail]
2. Evaluation Board
The Evaluation Board for the BPR is used for ease of testing. It provides convenient
access to all 14 pins and the data output ports. Utilizing a zero-insertion force
configuration, the BPR can be mounted without the need for soldering as a user-friendly
interfacing solution. The EVB is mounted on a base plate. The base plate can be further
mounted to other structures using the four ¼-20 threaded through holes
2.1 Device Mounting Procedure
i) Place the BPR onto the evaluation board as show in Fig. 2. Pay attention to its
orientation. The label P and N denotes the positive and negative RF output
ports.
ii) Align pins down into pin chuck. Make sure that they line up and don’t cross
over.
iii) Mount BPR to Evaluation board using the four 2-56 screws provided.
iv) Once secured clamp pins down in pin chuck, as shown in Fig. 2.
Figure 2. BPR mounting procedure
4x 2-25
screws

Optilab, LLC
600 E. Camelback Road, Phoenix, AZ 85012
Phone: [phone], Fax: [phone], Email: [e-mail]
2.2 Schematic of Evaluation Board
Fig.4 shows the schematic of evaluation board.
Figure 4. Schematic of Evaluation Board
An external power supply is connected through the power connecting plug. BWM (JP3)
and BWA (JP4) are used to select bandwidth setting. Mode (JP6) is for operation mode
selection. OA (R3) is used AGC mode for constant output amplitude adjustment. GC
(R1) is used manual gain mode for constant gain setting. Test Pins PIN7+/- and PIN8+/-
are located on the two ends of R5 and R6 respectively.
2.3 Default Setting
Figure 5 shows an evaluation board in the default setting. Black jumpers (included in the
shipment) can be used to make connections between two pins adjacent to each other.
The evaluation board has been preset to MGC mode with the highest bandwidth setting.
Both PDs are reversed biased at Vcc. The TIA gain is maximized (GC = Vcc).

Optilab, LLC
600 E. Camelback Road, Phoenix, AZ 85012
Phone: [phone], Fax: [phone], Email: [e-mail]
Figure 5. EVB Default Setting and Controls
2.3.1 How to use manual gain control (MGC) mode
To use manual gain control mode, leave evaluation board in its default state, ensure both
JP6 and JP8 are jumped on pin 1 and 2. Adjust the differential gain by adjusting the
potentiometer GC (R1), clockwise to increase gain.
Figure 6. BPR-EVB in MGC Mode
BWM
BWA
OA
GC
MODE
GC
MODE

Optilab, LLC
600 E. Camelback Road, Phoenix, AZ 85012
Phone: [phone], Fax: [phone], Email: [e-mail]
2.3.2 How to use automatic gain control (AGC) mode
To use automatic gain control mode, MC pin has to be set to float and GC pin also has
to be floating. First float MODE (JP6). Then remove jumper on pin 11. Adjust
potentiometer R3 (OA) to the desired output amplitude, clockwise to increase amplitude.
Figure 7. BPR-EVB in AGC Mode
2.4 Operation Instruction
Before powering up BPR make sure evaluation board is at factory default setting (see Fig.
5). This is especially important for first time user. Mount the BPR firmly as instructed in
section 2.1. Use ESD strap during the handling.
Connect both RF output ports to the receiver instrument (e.g., CDR circuit, oscilloscope
etc.) use a pair of RF cables with GPPO (SMPM) connector. These two RF output ports
need AC coupling. Check the specification and setting of the instrument that BPR is
connected to. If DC coupling scheme is used in the corresponding instrument, use
external DC blocks in between. DC coupling causes high current consumption of BPR
which may damage its TIA!!
Connect the 2-pin power connector on the right edge of evaluation board to the external
DC power supply. A regulated DC voltage source with low voltage ripple is
recommended. Set the current limit to 93 mA. Ramp up the voltage to 3.3V. Now BPR is
operated in MGC mode.
To use AGC mode, ramp down DC power then turn off. Follow the instruction in section
2.3.2 to make proper jumpers then ramp up DC power to 3.3V.
MODE
OA
Jumpers are
removed