ADL5306ACPZ-R2 Analog Devices Inc, ADL5306ACPZ-R2 Datasheet

IC CONVERT LOGARITH 60DB 16LFCSP

ADL5306ACPZ-R2

Manufacturer Part Number
ADL5306ACPZ-R2
Description
IC CONVERT LOGARITH 60DB 16LFCSP
Manufacturer
Analog Devices Inc
Type
Logarithmic Converterr
Datasheet

Specifications of ADL5306ACPZ-R2

Design Resources
Interfacing ADL5315 to Translinear Logarithmic Amplifier (CN0056) Interfacing ADL5317 High Side Current Mirror to a Translinear Logarithmic Amplifier in an Avalanche Photodiode Power Detector
Applications
Fiber Optics
Mounting Type
Surface Mount
Package / Case
16-LFCSP
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Other names
ADL5306ACPZ-R2TR
FEATURES
Optimized for fiber optic photodiode interfacing
Measures current over 3 decades
Single- or dual-supply operation (3 V to ±5.5 V total)
Full log-ratio capabilities
Temperature stable
Nominal slope of 10 mV/dB (200 mV/decade)
Nominal intercept of 1 nA (set by external resistor)
Rapid response time for a given current level
Miniature 16-lead chip scale package (LFCSP 3 mm × 3 mm)
Low power: ~5 mA quiescent current
APPLICATIONS
Low cost optical power measurement
Wide range baseband logarithmic compression
Measurement of current and voltage ratios
Optical absorbance measurement
GENERAL DESCRIPTION
The ADL5306
optimized for determining optical power in fiber optic systems. The
ADL5306 is derived from the AD8304 and AD8305 translinear
logarithmic converters. This family of devices provides wide
measurement dynamic range in a versatile and easy-to-use form. A
single-supply voltage between 3 V and 5.5 V is adequate; dual
supplies may optionally be used. Low quiescent current (5 mA
typical) permits use in battery-operated applications.
I
the collector current of an optimally scaled NPN transistor that
converts this current to a voltage (V
relationship. A second converter is used to handle the reference
current, I
above ground (0.5 V). This is generally acceptable for photodiode
applications where the anode does not need to be grounded.
Similarly, this bias voltage is easily accounted for in generating I
The logarithmic front end’s output is available at VLOG.
The basic logarithmic slope at this output is 200 mV/decade
(10 mV/dB) nominal; a 60 dB range corresponds to a 600 mV
output change. When this voltage (or the buffer output) is applied
to an ADC that permits an external reference voltage to be
employed, the ADL5306’s 2.5 V voltage reference output at VREF
can be used to improve scaling accuracy.
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.
PD
, the 100 nA to 100 µA input current applied to the INPT pin, is
Law conformance 0.1 dB from 100 nA to 100 μA
Optional adjustment of slope and intercept
REF
, applied to IREF. These input nodes are biased slightly
is a low cost microminiature logarithmic converter
BE
) with a precise logarithmic
REF
.
Low Cost Logarithmic Converter
60 dB Range (100 nA to 100 µA)
FUNCTIONAL BLOCK DIAGRAM
The logarithmic intercept (reference current) is nominally
positioned at 1 nA by using the externally generated, 100 µA I
current provided by a 200 kΩ resistor connected between VREF, at
2.5 V, and IREF, at 0.5 V. The intercept can be adjusted over a
narrow range by varying this resistor. The part can also operate in a
log-ratio mode, with limited accuracy, where the numerator and
denominator currents are applied to INPT and IREF, respectively.
A buffer amplifier is provided to drive substantial loads, raise the
basic 10 mV/dB slope, serve as a precision comparator (threshold
detector), or implement low-pass filters. Its rail-to-rail output stage
can swing to within 100 mV of the positive and negative supply
rails, and its peak current-sourcing capacity is 25 mA.
A fundamental aspect of translinear logarithmic converters is that
small-signal bandwidth falls as current level diminishes, and low
frequency noise-spectral density increases. At the 100 nA level, the
ADL5306’s bandwidth is about 100 kHz; it increases in proportion
to I
level at low currents can be addressed by using a buffer amplifier to
realize low-pass filters of up to three poles.
The ADL5306 is available in a 16-lead LFCSP package and is
specified for operation from–40°C to +85°C.
1kΩ
1nF
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.326.8703
V
Protected by US Patents 4,604,532 and 5,519,308; other patents pending.
200kΩ
BIAS
R
1kΩ
1nF
PD
REF
I
PD
1nF
up to a maximum of about 10 MHz. The increase in noise
VSUM
VREF
IREF
INPT
NC
0.5V
0.5V
Figure 1. Functional Block Diagram
20kΩ
© 2003 Analog Devices, Inc. All rights reserved.
COMM
VNEG
Q2
Q1
80kΩ
2.5V
V
V
BE2
BE1
COMPENSATION
GENERATOR
TEMPERATURE
VPOS
BIAS
+5V
COMM
ADL5306
COMM
14.2kΩ
6.69kΩ
0.2 log
www.analog.com
I
LOG
10
451Ω
( )
1nA
I
PD
03727-0-001
REF
VOUT
SCAL
BFIN
VLOG

Related parts for ADL5306ACPZ-R2

ADL5306ACPZ-R2 Summary of contents

Page 1

FEATURES Optimized for fiber optic photodiode interfacing Measures current over 3 decades Law conformance 0.1 dB from 100 nA to 100 μA Single- or dual-supply operation ( ±5.5 V total) Full log-ratio capabilities Temperature stable Nominal slope of ...

Page 2

ADL5306 TABLE OF CONTENTS Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 4 Pin Configuration and Pin Function Descriptions...................... 5 Typical Performance Characteristics ............................................. 6 General Structure.............................................................................. 9 Theory............................................................................................ 9 Managing Intercept and Slope .................................................. 10 REVISION HISTORY Rev. 0: Initial Version Response ...

Page 3

SPECIFICATIONS Table 25° Parameter INPUT INTERFACE Specified Current Range Input Current Min/Max Limits Reference Current Range REF Summing Node Voltage Temperature Drift ...

Page 4

ADL5306 ABSOLUTE MAXIMUM RATINGS Table 2. ADL5306 Absolute Maximum Ratings Parameter Supply Voltage V – Input Current Internal Power Dissipation θ JA Maximum Junction Temperature Operating Temperature Range Storage Temperature Range Lead Temperature Range (Soldering 60 sec) ...

Page 5

PIN CONFIGURATION AND PIN FUNCTION DESCRIPTIONS Table 3. Pin Function Descriptions Pin No. Mnemonic Function 1 NC N/A 2 VREF Reference Output Voltage of 2 IREF Accepts (Sinks) Reference Current I 4 INPT Accepts (Sinks) Photodiode Current I ...

Page 6

ADL5306 TYPICAL PERFORMANCE CHARACTERISTICS ( 200 kΩ 25°C, unless otherwise noted REF A 1 –40°C, 0°C, +25°C, +70°C, +85° 1.0 ...

Page 7

I (A) REF Figure 9. V vs. I for Multiple Values of I LOG REF (Decade Steps from mA) ...

Page 8

ADL5306 10 5 100nA 0 –5 –10 –15 –20 –25 –30 –35 –40 100 1k 10k 100k 1M FREQUENCY (Hz) Figure 15. Small-Signal AC Response (5% Sine Modulation), from for I in Decade Steps from 10 ...

Page 9

GENERAL STRUCTURE The ADL5306 addresses a wide variety of interfacing conditions to meet the needs of fiber optic supervisory systems, and is useful in many nonoptical applications. This section explains the structure of this unique style of translinear log amp. ...

Page 10

ADL5306 It is apparent that this output should be zero for I would need to swing negative for smaller values of input current. To avoid this, I would need small as the REF smallest value of I ...

Page 11

APPLICATIONS The ADL5306 is easy to use in optical supervisory systems and in similar situations where a wide-ranging current converted to its logarithmic equivalent (i.e., represented in decibel terms). Basic connections for measuring a single current input ...

Page 12

ADL5306 The use of a negative supply allows the summing node placed at ground level whenever the input transistor (Q1 in Figure 1) has a sufficiently negative bias on its emitter. When V = –0.5 ...

Page 13

HP3577A NETWORK ANALYZER OUTPUT INPUT R INPUT A INPUT B 16 POWER COMM SPLITTER NC 1 VREF 2 R2 +IN B AD8138 IREF 3 EVALUATION R1 BOARD INPT A 4 VSUM 5 1kΩ 1kΩ 1nF 1nF Figure 26. Configuration for ...

Page 14

ADL5306 EVALUATION BOARD An evaluation board is available for the ADL5306, the schematic of which is shown in 29. It can be configured for a wide variety of experiments. The buffer gain is factory-set to unity, providing Table 4. Evaluation ...

Page 15

COMM COMM NC 1 R18 R19 VREF VREF Ω OPEN 200k Ω REF IREF 3 IREF OPEN R13 Ω INPT 4 SC-STYLE VSUM 1nF ...

Page 16

ADL5306 OUTLINE DIMENSIONS PIN 1 INDICATOR 12°MAX 1.00 0.90 0.80 SEATING PLANE ESD CAUTION 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. ...

Related keywords