ADN2880ACHIPS - Analog Devices

3.2 Gbps 3.3 V Low Noise

Transimpedance Amplifier

Preliminary Technical Data

ADN2880

Rev. PrC

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 owners.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781.329.4700 www.analog.com

FEATURES

Technology: high performance SiGe

Bandwidth: 2.1GHz minimum

Input noise current density: 8 pA√Hz

Optical sensitivity: −24 dBm

Differential transimpedance: 5000 V/A

Power dissipation: 75 mW

Differential output swing: 250 mV p-p

Input current overload: +3.25 dBm

Output resistance: 50 Ω/side

Low-freq cutoff: 20 kHz

On-chip PD filter: RF = 200 Ω CF = 20 pF

RSSI voltage and current ratio: 0.8V/mA

Die size: 0.7 mm × 1.2 mm

APPLICATIONS

3.2 Gbps optical modules

SFF-8472 compliant receivers

PIN/APD-TIA receive optical subassembly

SONET/GbE/FC optical receivers, transceivers, transponders

PRODUCT DESCRIPTION

The ADN2880 is a compact, high performance 3.3 V power

supply SiGe transimpedance amplifier (TIA) optimized for

small-form-factor pluggable (SFP) optical receivers, up to

3.2 Gbps SFF/SPF optical receivers, and meets OC48 SR/IR

sensitivity requirements. The ADN2880 is a single-chip

solution for detecting photodiode current with a differential

output voltage. The ADN2880 features low input referred

noise current of 400 nA enabling −24 dBm sensitivity; 2.1

GHz minimum BW enables up to 3.2 Gbps operation; +3.25

dBm nominal operation at 10 dB extinction ratio. RSSI

output signal proportional to average input current is

available for monitoring and alarm generation. To facilitate

assembly in small form factor packages such as a TO-46 or

TO-56 header, the ADN2880 integrates the photodiode filter

network on chip and features 20 kHz low frequency cutoff

without any external components. The ADN2880 chip area

is less than 1 mm2, operates with a 3.3 V power supply and is

available in die form.

Figure 1. ADN2880 Block Diagram

1100Ω50Ω50Ω

0.85V 5mA

200Ω

20pF

OUT

OUTB

GND GND CAP

FILTER

VCC

VCC_FILTER

3.3V

1400

Ω

RSSI

ADN2880 Preliminary Technical Data

Rev. PrC | Page 2 of 9

TABLE OF CONTENTS

Electrical Specifications................................................................... 3

Absolute Maximum Ratings............................................................ 4

ESD Caution.................................................................................. 4

Pad Descriptions............................................................................... 5

Pad Layout..........................................................................................6

Pad Coordinates ............................................................................6

Die Information.............................................................................6

Assembly Recommendations...........................................................7

REVISION HISTORY

07/04—Revision PrB

11/04 – Revision C – RSSI added.

Preliminary Technical Data ADN2880

Rev. PrC | Page 3 of 9

ELECTRICAL SPECIFICATIONS

Table 1.

Parameter Conditions1 Min Typ Max Unit

DYNAMIC PERFORMANCE

Bandwidth (BW)2 −3 dB 2.1 2.3 GHz

Total Input RMS Noise (IRMS)2 DC to 3.2 GHz 375 400 nA

Small Signal Transimpedance (ZT) 100 MHz 4000 5000 6000 V/A

Low Frequency Cutoff CAP = Open

CAP = 1nF

kHz

Output Return Loss2 DC to 3.2 GHz, differential −20 −12 dB

Input Overload Current3 Pavg TBD 3.25 dBm

Maximum Output Swing pk-pk diff, IIN,PK- PK = 2.0 mA 180 250 350 mV

Output Data Transition Time 20% to 80% rise/fall time IIN,PK- PK = 2.5 mA 55 ps

PSRR < 10 MHz −35 dB

Group Delay Variation 50 MHz to 3.2 GHz TBD ps

Transimpedance Ripple 50 MHz to 3.2 GHz TBD dB

Total Jitter2 10 µA < IIN,PK- PK ≤ 100 µA TBD TBD ps

100 µA < IIN,PK- PK ≤ 2.0 µA TBD TBD ps

Deterministic Jitter2 10 µA < IIN,PK- PK ≤ 100 µA 4 ps

100 µA < IIN,PK- PK ≤ 2.0 µA 8 ps

DC PERFORMANCE

Power Dissipation IIN,AVE = 0 mA 50 75 120 mW

Input Voltage 0.85 V

Output Common-Mode Voltage DC terminated to Vcc Vcc – 0.12 V

Output Impedance Single-ended 50 Ω

PD FILTER Resistance RF 200 Ω

PD FILTER Capacitance CF 20 pF

RSSI Sensitivity IIN, AVE = 0 uA to 1 mA 0.8 V/mA

RSSI Offset IIN, AVE = 0 uA TBD mV

1 Min/Max Vcc = +3.3V ± 0.3V, Tambient = −40 °C to +95°C; Typ Vcc=3.3V, Tambient = +25C

2 Photodiode capacitance CD = 0.7 pF ± 0.15 pF, photodiode resistance = 5 Ω input wire bond inductance LIN = 0.3nH ± 0.1nH, Output bond wire inductance LOUT,OUTB =

0.8nH ± 0.1nH Load impedance = 50 Ω (each output, ac-coupled)

3 10-10 BER, 10dB ER, 0.85 A/W PIN responsivity

ADN2880 Preliminary Technical Data

Rev. PrC | Page 4 of 9

ABSOLUTE MAXIMUM RATINGS

Table 2.

Parameters Ratings

Supply Voltage (Vcc to GND) 5 V

Internal Power Dissipation

Output Short Circuit Duration TBD

Maximum Input Current 10 mA

Storage Temperature Range −65°C to +125°C

Operating Ambient Temperature Range −40°C to +95°C

Maximum Junction Temperature 165°C

Die Attach Temperature (<60 seconds) 450°C

Stresses above those listed under ‘Absolute Maximum Rating’

may cause permanent damage to the device. This is a stress

rating only and functional operation of the device at these or

any other conditions above those indicated in the operational

section of this specification is not implied. Exposure to absolute

maximum rating conditions for extended periods may affect

device reliability.

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. 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.

Preliminary Technical Data ADN2880

Rev. PrC | Page 5 of 9

PAD DESCRIPTIONS

Table 3.

PAD # PAD FUNCTION

1 GND Ground (input return).

2 IN Current Input. Bond directly to PD anode.

3 TEST Test Probe Pad. Leave Floating.

4 FILTER Filter Output.

5 FILTER Filter Output

6 GND Ground.

7 RSSI Voltage Output (provides average input current reading)

8 CAP Low Frequency Setpoint. Connect with 1 nF capacitance to GND for < 30 kHz.

9 GND Ground.

10 GND Ground (output return).

11 OUTB Negative Output. Drives 50 ohm termination (ac or dc termination).

12 OUT Positive Output. Drives 50 ohm termination (ac or dc termination).

13 GND Ground (output return).

14 GND Ground

15 VCCFILTER Filter Supply. Connect to Vcc to enable on-chip 200 Ω*20 pf filter.

16 VCC 3.3 V Positive Supply. Recommended bypass to GND is 100 pF RF capacitor.

17 VCC 3.3 V Positive Supply. Recommended bypass to GND is 100 pF RF capacitor.

FILTER

RSSI

ADN2880 Preliminary Technical Data

Rev. PrC | Page 6 of 9

PAD LAYOUT

Figure 2.. Pad Layout

PAD COORDINATES

Table 4.

PAD # PAD X (um) Y (um)

1 GND −500 260

2 IN −500 130

3 TEST −500 10

4 FILTER −500 −120

5 FILTER −500 −260

6 GND −350 −260

7 RSSI −200 −260

8 CAP −50 −260

9 GND 130 −260

10 GND 500 −260

11 OUTB 350 −60

12 OUT 350 60

13 GND 500 260

14 GND 130 260

15 VCCFILTER −50 260

16 VCC −200 260

17 VCC −350 260

DIE INFORMATION

Die Size

0.7mm × 1.2mm

(edge-edge including 1mil scribe)

Die Thickness

10mils = 0.25mm

Passivation Openings

0.075 mm × 0.075 mm

(pads 1-8, 9, 10, 13, 15, 16, 17)

0.144mm × 0.075mm

(pads 9, 11, 12, 14)

Passivation Composition

5000Å Si3N4 (top)

+5000 Å SiO2 (bot)

Pad Composition

Al/1%Cu

Backside Contact

FILTER

RSSI

Preliminary Technical Data ADN2880

Rev. PrC | Page 7 of 9

ASSEMBLY RECOMMENDATIONS

560pF

200pF

1000pF

VPD VCC

OUTB OUT

Figure 3. 5-Pin TO-46 with External Photodiode Supply VPD Connected through FILTER Pin

1× Vendor Specific (0.3 mm × 0.3 mm) 2.5 Gbps Photo Diode

1× ADN2880 (0.7mm × 1.2 mm) Analog Devices SiGe 3.2 Gbps Transimpedance Amplifier

1× 200 pF RF Single-Layer Capacitor

1× 560 pF RF Single Layer Capacitor

1x 1000pF Ceramic Capacitor

Notes

Minimize all GND bond wire lengths

Minimize IN, OUT and OUTB bond wire lengths

Maintain symmetry in length and orientation between OUT and OUTB bond wires

Maintain symmetry between IN and OUT/OUTB bond wires

ADN2880 Preliminary Technical Data

Rev. PrC | Page 8 of 9

200pF

VCC

OUTB OUT

Ceramic

Standoff

Figure 4. Recommended Layout of 4-Pin TO-46

1× Vendor Specific (0.3 mm × 0.3 mm) 2.5 Gbps Photo Diode

1× ADN2880 (0.7mm × 1.2 mm) Analog Devices SiGe 3.2 Gbps Transimpedance Amplifier

1× 200 pF RF Single-Layer Capacitor

1× Ceramic Standoff

1x 1000pF Ceramic Capacitor

Notes

Minimize all GND bond wire lengths

Minimize IN, OUT and OUTB bond wire lengths

Maintain symmetry in length and orientation between OUT and OUTB bond wires

Maintain symmetry between IN and OUT/OUTB bond wires

Preliminary Technical Data ADN2880

Rev. PrC | Page 9 of 9

ORDERING GUIDE

Model Temperature Package Description Package Option

ADN2880XCHIPS-WP -40oC to 95oC NA Tested Die

registered trademarks are the property of their respective companies.

PR04945–0–11/04(PrC)