Datasheet SA5211D Datasheet (Philips)

INTEGRATED CIRCUITS

SA5211

Transimpedance amplifier (180MHz)

Product specification Replaces datasheet NE/SA5211 of 1995 Apr 26 IC19 Data Handbook

 

1998 Oct 07

Philips Semiconductors Product specification

SYMBOL

PARAMETER

RATING

UNIT

SA521 1Transimpedance amplifier (180MHz)

DESCRIPTION

The SA521 1 is a 28kΩ transimpedance, wide-band, low noise amplifier with differential outputs, particularly suitable for signal recovery in fiber optic receivers. The part is ideally suited for many other RF applications as a general purpose gain block.

FEA TURES

•Extremely low noise:

1.8pA  Hz



•Single 5V supply

•Large bandwidth: 180MHz

•Differential outputs

•Low input/output impedances

•High power supply rejection ratio

•28kΩ differential transresistance

APPLICATIONS

•Fiber optic receivers, analog and digital

•Current-to-voltage converters

•Wide-band gain block

PIN CONFIGURATION

D Package

1

GND

2

GND

2

3

NC

4

I

IN

5

NC

6

V

CC1

78

V

CC2

TOP VIEW

Figure 1. Pin Configuration

•Medical and scientific Instrumentation

•Sensor preamplifiers

•Single-ended to differential conversion

•Low noise RF amplifiers

•RF signal processing

14

OUT (–)

13

GND

12

OUT (+)

11

GND

10

GND

9

GND

SD00318

2

1

1 1

ORDERING INFORMATION

DESCRIPTION TEMPERATURE RANGE ORDER CODE DWG #

14-Pin Plastic Small Outline (SO) Package -40 to +85°C SA5211D SOT108-1

ABSOLUTE MAXIMUM RATINGS

V

CC

T

A

T

J

T

STG

P

D MAX

I

IN MAX

θ

JA

NOTES:

1. Maximum dissipation is determined by the operating ambient temperature and the thermal resistance: =125°C/W

θ

2. The use of a pull-up resistor to V

JA

Power supply 6 V Operating ambient temperature range -40 to +85 °C Operating junction temperature range -55 to +150 °C Storage temperature range -65 to +150 °C Power dissipation, TA=25°C (still-air) Maximum input current

2

1

1.0 W 5 mA

Thermal resistance 125 °C/W

, for the PIN diode is recommended.

CC

1998 Oct 07 853-1799 20142

2

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

RECOMMENDED OPERATING CONDITIONS

SYMBOL PARAMETER RATING UNIT

V

CC

T

A

T

J

DC ELECTRICAL CHARACTERISTICS

Min and Max limits apply over operating temperature range at VCC=5V, unless otherwise specified. Typical data apply at VCC=5V and TA=25°C.

SYMBOL

V

IN

V

±

O

V

OS

I

CC

I

OMAX

I

IN

I

IN MAX

NOTES:

1. Test condition: output quiescent voltage variation is less than 100mV for 3mA load current.

Input bias voltage 0.55 0.8 1.00 V Output bias voltage 2.7 3.4 3.7 V Output offset voltage 0 130 mV Supply current 20 26 31 mA Output sink/source current Input current

(2% linearity) Maximum input current

overload threshold

Supply voltage 4.5 to 5.5 V Ambient temperature range -40 to +85 °C Junction temperature range -40 to +105 °C

PARAMETER TEST CONDITIONS Min Typ Max UNIT

1

Test Circuit 8,

Procedure 2

Test Circuit 8,

Procedure 4

3 4 mA

±20 ±40 µA

±30 ±60 µA

1998 Oct 07

3

Philips Semiconductors Product specification

1

SA521 1Transimpedance amplifier (180MHz)

AC ELECTRICAL CHARACTERISTICS

Typical data and Min and Max limits apply at VCC=5V and TA=25°C

SYMBOL

R R R R f R

C

T

O

T

O

3dB

IN IN

Transresistance (differential output) Output resistance (differential output) DC tested 30 Ω Transresistance (single-ended output) Output resistance (single-ended output) DC tested 15 Ω Bandwidth (-3dB) Input resistance 200 Ω

Input capacitance 4 pF

∆R/∆V Transresistance power supply sensitivity V ∆R/∆T Transresistance ambient temperature sensitivity ∆T

I

N

I

T

RMS noise current spectral density (referred to input)

Integrated RMS noise current over the bandwidth (referred to input)

CS=0

CS=1pF ∆f = 100MHz 21 nA

PSRR

Power supply rejection ratio (V

= V

CC1

PSRR Power supply rejection ratio2 (V

PSRR Power supply rejection ratio (ECL configuration)

V

OMAX

V

IN MAX

t

R

Maximum differential output voltage swing Maximum input amplitude for output duty cycle of

3

50±5% Rise time for 50mV output signal

NOTES:

1. Package parasitic capacitance amounts to about 0.2pF

2. PSRR is output referenced and is circuit board layout dependent at higher frequencies. For best performance use RF filter in V

3.

Guaranteed by linearity and overload tests.

4. t

defined as 20-80% rise time. It is guaranteed by -3dB bandwidth test.

R

PARAMETER TEST CONDITIONS Min Typ Max UNIT

DC tested R

Test Circuit 8, Procedure 1

DC tested

T

A

Test circuit 1

CC

= T

A

= ∞

L

= ∞

R

L

= 25°C

= 5±0.5V 3.7 %/V

A MAX-TA MIN

21 28 36 kΩ

10.5 14 18.0 kΩ

180 MHz

0.025 %/°C

Test Circuit 2

f = 10MHz T

= 25°C

A

T

= 25°C

A

1.8 pA/√Hz

Test Circuit 2

∆f = 50MHz 13 ∆f = 100MHz 20 nA ∆f = 200MHz 35

∆f = 50MHz 13

∆f = 200MHz 41

CC

= 0.1V

23 32 dB

CC2

2

)

DC tested, ∆V

Equivalent AC

Test Circuit 3

DC tested, ∆V

CC1

)

Equivalent AC

Test Circuit 4

CC2

DC tested, ∆V

)

Equivalent AC

CC

= 0.1V

45 65 dB

Test Circuit 5

2

f = 0.1MHz

Test Circuit 6

R

= ∞

L

Test Circuit 8, Procedure 3

23 dB

1.7 3.2 V

Test Circuit 7 160 mV

4

Test Circuit 7 0.8 1.8 ns

CC

P-P

lines.

1998 Oct 07

4

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

TEST CIRCUITS

ZO = 50

NETWORK ANALYZER

S-PARAMETER TEST SET

PORT 1

0.1µF

R = 1k

50

5V

V

CC1VCC2

IN DUT

GND

1

OUT

GND

PORT 2

0.1µF

33

0.1µF

33

2

Test Circuit 1

SPECTRUM ANALYZER

V

CC1VCC2

NC

IN DUT

GND

SINGLE-ENDED DIFFERENTIAL

V

OUT

RT[

RO[ Z

= 50

Z

O

= 50

R

L

5V

33

OUT

33

OUT

GND

1

2

R + 2 @ S21 @ RRT+

V

IN

1 ) S22

Ť

O

AV = 60DB

0.1µF

* 33 RO+ 2Z

1 * S22

= 50

Z

O

R

= 50

L

V

OUT

V

IN

1 ) S22

Ť

O

1 * S22

R + 4 @ S21 @ R

Ť

* 66

1998 Oct 07

Test Circuit 2

Figure 2. Test Circuits 1 and 2

5

SD00319

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

TEST CIRCUITS (Continued)

NETWORK ANALYZER

5V

10µF

0.1µF

IN

V

GND

CC1

16

1

CURRENT PROBE

1mV/mA

V

CC2

GND

33

2

OUT

0.1µF

PORT 1 PORT 2

100 BAL.

S-PARAMETER TEST SET

TRANSFORMER

NH0300HB

50 UNBAL.

CAL

TEST

Test Circuit 3

NETWORK ANALYZER

1998 Oct 07

5V

10µF

0.1µF

IN

V

CC2

GND

PORT 1 PORT 2

CURRENT PROBE

1mV/mA

16

V

CC1

OUT

1

GND

0.1µF

33

100

33

0.1µF

2

BAL.

Test Circuit 4

S-PARAMETER TEST SET

TRANSFORMER

NH0300HB

50 UNBAL.

CAL

TEST

SD00320

Figure 3. Test Circuits 3 and 4

6

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

TEST CIRCUITS (Continued)

NETWORK ANALYZER

5V

10µF

0.1µF

IN

V

GND

CC1

PORT 1 PORT 2

CURRENT PROBE

1mV/mA

16

V

CC2

OUT

1

GND

0.1µF

33

100

33

0.1µF

2

BAL.

S-PARAMETER TEST SET

TRANSFORMER

NH0300HB

50 UNBAL.

CAL

TEST

Test Circuit 5

NETWORK ANALYZER

S-PARAMETER TEST SET

GND

PORT 1 PORT 2

1998 Oct 07

5.2V

10µF

0.1µF

CURRENT PROBE

1mV/mA

16

OUT

V

GND

CC2

2

0.1µF

33

100

33

0.1µF

BAL.

TRANSFORMER

NH0300HB

GND

1

IN

V

CC1

Test Circuit 6

50 UNBAL.

CAL

TEST

SD00321

Figure 4. Test Circuits 5 and 6

7

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

TEST CIRCUITS (Continued)

PULSE GEN.

V

CC1VCC2

0.1µF

33

0.1µF

50

GND

1

DUT

OUT

GND

33

0.1µF

2

IN

1k

A

= 50Ω

Z

O

OSCILLOSCOPE

B

ZO = 50Ω

Measurement done using

differential wave forms

Test Circuit 7

Figure 5. Test Circuit 7

SD00322

1998 Oct 07

8

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

TEST CIRCUITS (Continued)

Typical Differential Output Voltage

vs Current Input

5V

OUT +

IN

DUT

GND

1

OUT –

GND

2

CURRENT INPUT (µA)

IIN (µA)

2.00

1.60

1.20

0.80

0.40

0.00

–0.40

–0.80

DIFFERENTIAL OUTPUT VOLTAGE (V)

–1.20

–1.60

–2.00

–100 –80 –60 –40 –20 0 20 40 60 80 100

+

(V)

V

OUT

–

1998 Oct 07

NE5211 TEST CONDITIONS

Procedure 1

Procedure 2

Procedure 3

Procedure 4

Test Circuit 8

Figure 6. Test Circuit 8

measured at 15µA

R

T

= (VO1 – VO2)/(+15µA – (–15µA))

R

T

Where: V

Linearity = 1 – ABS((V Where: V

V

OMAX

Where: VO7 Measured at IIN = +65µA

IIN Test Pass Conditions: V

O7

Where: V

Measured at IIN = +15µA

O1

V

Measured at IIN = –15µA

O2

– VOB) / (VO3 – VO4))

OA

Measured at IIN = +30µA

O3

V

Measured at IIN = –30µA

O4

VOA+ RT@ () 30A) ) V

VOB+ RT@ (* 30A) ) V

= VO7 – V

– VO5 > 20mV and V06 – VO5 > 50mV

O8

Measured at IIN = –65µA

V

O8

Measured at IIN = +40µA

O5

V

Measured at IIN = –400µA

O6

V

Measured at IIN = +65µA

O7

Measured at IIN = –65µA

V

O8

9

OB

SD00331

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

TYPICAL PERFORMANCE CHARACTERISTICS

NE5211 Supply Current

vs Temperature

30

28

26

CC2

24

CC1

(I + I )

22

TOTAL SUPPLY CURRENT (mA)

20

18

–60 –20 0 20 40 60 80 100 120

5.5V

5.0V

4.5V

–40

AMBIENT TEMPERATURE (°C)

NE5211 Input Bias Voltage

vs Temperature

950

900

850

800

750

700

INPUT BIAS VOLTAGE (mV)

650

5.5V

4.5V

–60 –20 0 20 40 60 80 100 120–40 140

AMBIENT TEMPERATURE (°C)

140

NE5211 Output Bias Voltage

vs Temperature

3.50 VCC = 5.0V

3.45

PIN 14

3.40

3.35

PIN 12

3.30

OUTPUT BIAS VOLTAGE (V)

3.25

–60 –20 0 20 40 60 80 100 120–40 140

AMBIENT TEMPERATURE (°C)

NE5211 Output Bias Voltage

4.1

3.9

3.7

3.5

3.3

3.1

2.9

OUTPUT BIAS VOLTAGE (V)

2.7 –60 –20 0 20 40 60 80 100 120–40 140

vs Temperature

PIN 14

5.5V

5.0V

4.5V

AMBIENT TEMPERATURE (°C)

NE5211 Output Voltage

vs Input Current

2.0

0

–55°C

DIFFERENTIAL OUTPUT VOLTAGE (V)

+125°C

–2.0

–100.0 0 +100.0

+25°C +85°C

INPUT CURRENT (µA)

+85°C

+125°C

–55°C

NE5211 Differential Output Voltage

0

4.5V

5.5V

vs Input Current

5.5V5.0V

4.5V

5.0V

INPUT CURRENT (µA)

2.0

DIFFERENTIAL OUTPUT VOLTAGE (V) –2.0

–100.0 0 +100.0

+25°C

NE5211 Output Offset Voltage

vs Temperature

40

VOS = V

20

0

4.5V

–20 –40

5.0V

–60 –80

5.5V

–100 –120

OUTPUT OFFSET VOLTAGE (mV)

–140

–60 –20 0 20 40 60 80 100 120–40 140

AMBIENT TEMPERATURE (°C)

OUT12

– V

1998 Oct 07

OUT14

NE5211 Differential Output Swing

vs Temperature

4.0

3.8

DC TESTED R

= ∞

L

3.6

5.5V

3.4

3.2

5.0V

3.0

2.8

4.5V

2.6

2.4

DIFFERENTIAL OUTPUT SWING (V)

2.2 –60 –20 0 20 40 60 80 100 120–40 140

AMBIENT TEMPERATURE (°C)

Figure 7. Typical Performance Characteristics

10

NE5211 Output Voltage

vs Input Current

+125°C

4.5

OUTPUT VOLTAGE (V)

2.5 –100.0 0 +100.0

INPUT CURRENT (µA)

+85°C

+25°C

+125°C

+25°C

–55°C

+85°C

–55°C–55°C

+85°C

+25°C

SD00332

+125°C

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

TYPICAL PERFORMANCE CHARACTERISTICS (Continued)

NE5211 Gain vs Frequency NE5211 Gain vs Frequency

17 16 15 14 13

PIN 12

12

= 25°C

T

A

GAIN (dB)

R

= 50Ω

11

L

10

9 8

0.1 1 10 100 FREQUENCY (MHz)

5.5V

5.0V

4.5V

NE5211 Gain vs Frequency

17 16 15 14 13

PIN 12

12

V

= 5V

CC

GAIN (dB)

11 10

9 8

0.1 1 10 100 FREQUENCY (MHz)

–55°C

125°C

85°C 25°C

17 16 15 14 13

PIN 14

12

= 25°C

T

A

GAIN (dB)

11

= 50Ω

R

L

10

9 8

0.1 1 10 100 FREQUENCY (MHz)

NE5211 Gain vs Frequency

17 16 15 14 13

PIN 14

12

V

= 5V

CC

GAIN (dB)

11 10

9 8

0.1 1 10 100 FREQUENCY (MHz)

5.5V

5.0V

–55°C

4.5V

125°C

85°C

25°C

NE5211 Differential Transresistance

vs Temperature

33

Ω

DC TESTED

32

R

= ∞

L

31

30

5.5V

29

5.0V

28

4.5V

DIFFERENTIAL TRANSRESISTANCE (k )

27

–60 –40–20 0 20 40 10060 12080

AMBIENT TEMPERATURE (°C)

NE5211 Typical

Bandwidth Distribution

(70 Parts from 3 Wafer Lots)

60

PIN 12 SINGLE-ENDED

50

= 50Ω

R

L

40

30

20

POPULATION (%)

10

0

143 155 167 179 191 203

FREQUENCY (MHz)

VCC = 5.0V T

= 25°C

A

140

NE5211 Bandwidth

220

5.5V

200

5.0V

180

4.5V

160

140

BANDWIDTH (MHz)

120

100

–60 –40 –20 0 20 40 10060 12080

AMBIENT TEMPERATURE (°C)

1998 Oct 07

vs Temperature

PIN 12 SINGLE-ENDED

= 50Ω

R

L

NE5211 Gain and Phase

Shift vs Frequency

140

17 16 15 14 13 12

GAIN (dB)

PIN 12

11

V

10

= 5V

CC

= 25°C

T

A

9 8

0.1 1 10 100 FREQUENCY (MHz)

120

60

0

–60

–120

Figure 8. Typical Performance Characteristics (cont.)

11

NE5211 Gain and Phase

Shift vs Frequency

17 16 15 14

o

13 12

PIN 14

GAIN (dB)

PHASE ( )

11 10

9 8

= 5V

V

CC

= 25°C

T

A

0.1 1 10 100 FREQUENCY (MHz)

120

270

SD00333

o

PHASE ( )

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

TYPICAL PERFORMANCE CHARACTERISTICS (Continued)

NE5211 Output Resistance

vs Temperature

18

V

= 5.0V

CC

DC TESTED

17

Ω

16

15

14

OUTPUT RESISTANCE ( )

13

–60 –40 –20 0 20 40 10060 12080

PIN 14

PIN 12

AMBIENT TEMPERATURE (°C)

NE5211 Output Resistance

vs Frequency

40

Ω

35

PIN 12

30

T

= 25°C

A

25 20 15 10

5

OUTPUT RESISTANCE ( )

0

0.1 1 10 100

4.5V 5.0V

5.5V

FREQUENCY (MHz)

140

NE5211 Output Resistance

vs Temperature

18

PIN 12 DC TESTED

17

Ω

16

15

14

OUTPUT RESISTANCE ( )

13

–60 –40 –20 0 20 40 10060 12080

4.5V

5.0V

5.5V

AMBIENT TEMPERATURE (°C)

NE5211 Output Resistance

vs Frequency

80

Ω

70 60

VCC = 5.0V

50 40 30 20 10

OUTPUT RESISTANCE ( )

0

0.1 1 10 100 FREQUENCY (MHz)

+125°C +85°C

+25°C

–55°C

140

NE5211 Output Resistance

vs Temperature

19

PIN 14 DC TESTED

18

Ω

17

16

15

OUTPUT RESISTANCE ( )

14

–60 –40 –20 0 20 40 10060 12080

4.5V

5.0V

5.5V

AMBIENT TEMPERATURE (°C)

NE5211 Output Resistance

vs Frequency

80

Ω

70

VCC = 5.0V

60 50 40 30 20 10

OUTPUT RESISTANCE ( )

0

0.1 1 10 100 FREQUENCY (MHz)

PIN 14

140

PIN 12

NE5211 Power Supply Rejection Ratio

vs Temperature

40

V

= V

CC2

= ±0.1V

= 5.0V

CC1

38

∆V

CC

DC TESTED OUTPUT REFERRED

36

34

32

30

POWER SUPPLY REJECTION RATIO (dB)

28

–60 –40 –20 0 20 40 10060 12080

AMBIENT TEMPERATURE (°C)

1998 Oct 07

NE5211 Group Delay

vs Frequency

10

8 6 4 2 0

DELAY (ns)

0.1

20 40 60 80 100 120 140 160 180 200

140

FREQUENCY (MHz)

Figure 9. Typical Performance Characteristics (cont.)

12

SD00335

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

TYPICAL PERFORMANCE CHARACTERISTICS (Continued)

Output Step Response

VCC = 5V TA = 25°C

20mV/Div

0 2 4 6 8 10 12 14 16 18 20

Figure 10. Typical Performance Characteristics (cont.)

THEORY OF OPERATION

Transimpedance amplifiers have been widely used as the preamplifier in fiber-optic receivers. The SA5211 is a wide bandwidth (typically 180MHz) transimpedance amplifier designed primarily for input currents requiring a large dynamic range, such as those produced by a laser diode. The maximum input current before output stage clipping occurs at typically 50µA. The SA5211 is a bipolar transimpedance amplifier which is current driven at the input and generates a differential voltage signal at the outputs. The forward transfer function is therefore a ratio of the differential output voltage to a given input current with the dimensions of ohms. The main feature of this amplifier is a wideband, low-noise input stage which is desensitized to photodiode capacitance variations. When connected to a photodiode of a few picoFarads, the frequency response will not be degraded significantly. Except for the input stage, the entire signal path is differential to provide improved power-supply rejection and ease of interface to ECL type circuitry. A block diagram of the circuit is shown in Figure 11. The input stage (A1) employs shunt-series feedback to stabilize the current gain of the amplifier. The transresistance of the amplifier from the current source to the emitter of Q feedback resistor, R and emitter followers (A3 and A4) is about two. Therefore, the differential transresistance of the entire amplifier , R

V

(diff)

R

OUT

+

T

I

IN

The single-ended transresistance of the amplifier is typically 14.4kΩ. The simplified schematic in Figure 12 shows how an input current is

converted to a differential output voltage. The amplifier has a single input for current which is referenced to Ground 1. An input

current from a laser diode, for example, will be converted into a voltage by the feedback resistor R of the open loop gain of the circuit, A minimizes loading on Q1. The transistor Q4, resistor R7, and V provide level shifting and interface with the Q15– Q16 differential pair of the second stage which is biased with an internal reference, V

. The differential outputs are derived from emitter followers Q

B2

which are biased by constant current sources. The collectors of

Q

12

is approximately the value of the

3

=14.4kΩ. The gain from the second stage (A2)

F

is

T

+ 2RF+ 2(14.4K) + 28.8kW

. The transistor Q1 provides most

F

≈70. The emitter follower Q

VOL

B1

11

(ns)

– Q12 are bonded to an external pin, V

Q

11

SD00334

, in order to reduce

CC2

the feedback to the input stage. The output impedance is about 17Ω single-ended. For ease of performance evaluation, a 33Ω resistor is used in series with each output to match to a 50Ω test system.

BANDWIDTH CALCULATIONS

The input stage, shown in Figure 13, employs shunt-series feedback to stabilize the current gain of the amplifier. A simplified analysis can determine the performance of the amplifier. The equivalent input capacitance, CIN, in parallel with the source, IS, is approximately

7.5pF, assuming that C capacitance.

Since the input is driven by a current source the input must have a low input resistance. The input resistance, R incremental input voltage, V and can be calculated as:

V

R

IN

+

IN

+

I

IN

More exact calculations would yield a higher value of 200Ω. Thus C

and RIN will form the dominant pole of the entire amplifier;

IN

f

*3dB

Assuming typical values for RF = 14.4kΩ, RIN = 200Ω, CIN = 4pF

+

f

*3dB

The operating point of Q1, Figure 12, has been optimized for the lowest current noise without introducing a second dominant pole in the pass-band. All poles associated with subsequent stages have been kept at sufficiently high enough frequencies to yield an overall single pole response. Although wider bandwidths have been achieved by using a cascade input stage configuration, the present

2

solution has the advantage of a very uniform, highly desensitized frequency response because the Miller effect dominates over the external photodiode and stray capacitances. For example, assuming a source capacitance of 1pF, input stage voltage gain of 70, R

–

=0 where CS is the external source

S

, to the corresponding input current, I

IN

R

F

1 ) A

+

2p R

1

2p 4pF 200W

VOL

+

1

INCIN

+ 200MHz

14.4K 71

+ 203W

, is the ratio of the

IN

=

IN

1998 Oct 07

13

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

60Ω then the total input capacitance, C

= 4 pF which will lead to

IN

only a 12% bandwidth reduction.

NOISE

Most of the currently installed fiber-optic systems use non-coherent transmission and detect incident optical power. Therefore, receiver noise performance becomes very important. The input stage achieves a low input referred noise current (spectral density) of

2.9pA/√Hz

. The transresistance configuration assures that the external high value bias resistors often required for photodiode biasing will not contribute to the total noise system noise. The equivalent input quiescent current of Q

noise current is strongly determined by the

RMS

, the feedback resistor RF, and the

1

bandwidth; however, it is not dependent upon the internal Miller-capacitance. The measured wideband noise was 41nA RMS in a 200MHz bandwidth.

DYNAMIC RANGE CALCULATIONS

The electrical dynamic range can be defined as the ratio of maximum input current to the peak noise current:

Electrical dynamic range, D I

= 60µA and a wideband noise of IEQ=41nA

INMAX

external source capacitance of C

(Max. input current)

D

+

E

(Peak noise current)

DE(dB) + 20log

(2Ǹ41 10*9) (60mA)

(58nA)

In order to calculate the optical dynamic range the incident optical power must be considered.

For a given wavelength λ; Energy of one Photon =

Where h=Planck’s Constant = 6.6 ×10 c = speed of light = 3 × 10 c / λ = optical frequency

No. of incident photons/sec=

No. of generated electrons/sec =

where η = quantum efficiency

no. of generated electron hole paris

+

no. of incident photons

P

NI + h @

hs

@ e Amps (Coulombsńsec.)

l

where e = electron charge = 1.6 × 10

h@e

Responsivity R =

hs

l

I + P @ R

, in a 200MHz bandwidth assuming

E

= 1pF.

S

*6

(60 @ 10

)

+ 60dB

hc

watt sec (Joule)

l

-34

Joule sec.

8

m/sec

P

where P=optical incident power

hs

l

P

hs

h @

l

-19

Coulombs

Amp/watt

RMS

for an

Assuming a data rate of 400 Mbaud (Bandwidth, B=200MHz), the noise parameter Z may be calculated as:

I

EQ

Z +

qB

+

(1.6 @ 10

where Z is the ratio of

*9

41 @ 10

*19

)(200 @ 106)

noise output to the peak response to a

RMS

1

+ 1281

single hole-electron pair. Assuming 100% photodetector quantum efficiency, half mark/half space digital transmission, 850nm lightwave and using Gaussian approximation, the minimum required optical power to achieve 10

+ 12

hc

l

P

avMIN

-9

BER is:

BZ+ 12 @ 2.3 @ 10

*19

200 @ 106(1281) + 719nW +*31.5dBm

+ 1139nW +*29.4dBm

where h is Planck’s Constant, c is the speed of light, λ is the wavelength. The minimum input current to the SA5211, at this input power is:

*9

@ 1.6 @ 10

@

*19

Joule

sec

@ q + I

*19

I

avMIN

+ qP

avMIN

+

l

hc1Joule

707 @ 10

2.3 @ 10

= 500nA Choosing the maximum peak overload current of I

avMAX

=60µA, the

maximum mean optical power is:

P

avMAX

hcI

avMAX

+

lq

+

2.3 @ 10

1.6 @ 10

*19 *19

60 @ 10mA

+ 86mWor* 10.6dBm (optical)

Thus the optical dynamic range, DO is: D

= P

O

D

O

1. S.D. Personick, Plenum Press, NY, 1981, Chapter 3.

avMAX

+ P

avMAX

+ 20.8dB

INPUT

- P

= -4.6 -(-29.4) = 24.8dB.

avMIN

* P

Optical Fiber Transmission Systems

A1 A2

R

F

+*31.5 * (* 10.6)

avMIN

,

OUTPUT +

A3

A4

OUTPUT –

SD00327

Figure 11. SA5211 – Block Diagram

This represents the maximum limit attainable with the SA5211 operating at 200MHz bandwidth, with a half mark/half space digital transmission at 850nm wavelength.

1998 Oct 07

14

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

V

CC1

R

1

R

3

R

12

R

13

V

CC2

Q

INPUT

GND

PHOTODIODE

2

Q

1

3

R

2

R

5

R

Figure 12. Transimpedance Amplifier

V

CC

I

C1

R1

INPUT

I

IN

V

IN

I

B

Q1

I

F

R

F

Q2

R3

Q3

R2

V

EQ3

R4

SD00329

Figure 13. Shunt-Series Input Stage

APPLICATION INFORMATION

Package parasitics, particularly ground lead inductances and parasitic capacitances, can significantly degrade the frequency response. Since the SA5211 has differential outputs which can feed back signals to the input by parasitic package or board layout capacitances, both peaking and attenuating type frequency response shaping is possible. Constructing the board layout so that Ground 1 and Ground 2 have very low impedance paths has produced the best results. This was accomplished by adding a ground-plane stripe underneath the device connecting Ground 1,

Q

4

+

Q

15

R

14

R

7

4

GND

Q

16

R

15

VB2

2

Q

11

Q

12

OUT–

+

OUT+

SD00328

Pins 8–11, and Ground 2, Pins 1 and 2 on opposite ends of the SO14 package. This ground-plane stripe also provides isolation between the output return currents flowing to either V

or Ground

CC2

2 and the input photodiode currents to flowing to Ground 1. Without this ground-plane stripe and with large lead inductances on the board, the part may be unstable and oscillate near 800MHz. The easiest way to realize that the part is not functioning normally is to measure the DC voltages at the outputs. If they are not close to their quiescent values of 3.3V (for a 5V supply), then the circuit may be oscillating. Input pin layout necessitates that the photodiode be physically very close to the input and Ground 1. Connecting Pins 3 and 5 to Ground 1 will tend to shield the input but it will also tend to increase the capacitance on the input and slightly reduce the bandwidth.

As with any high-frequency device, some precautions must be observed in order to enjoy reliable performance. The first of these is the use of a well-regulated power supply. The supply must be capable of providing varying amounts of current without significantly changing the voltage level. Proper supply bypassing requires that a good quality 0.1µF high-frequency capacitor be inserted between V

CC1

and V

, preferably a chip capacitor, as close to the package

CC2

pins as possible. Also, the parallel combination of 0.1µF capacitors with 10µF tantalum capacitors from each supply, V

CC1

and V

CC2

, to the ground plane should provide adequate decoupling. Some applications may require an RF choke in series with the power supply line. Separate analog and digital ground leads must be maintained and printed circuit board ground plane should be employed whenever possible.

Figure 14 depicts a 50Mb/s TTL fiber-optic receiver using the BPF31, 850nm LED, the SA5211 and the SA5214 post amplifier.

1998 Oct 07

15

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

+V

CC

47µF

C1

GND

C2

CC

C9

R3 47k

C11

.01µF

pin(s).

D1

LED

100pF

C13

V

LED

1

C

2

PKDET

THRESH

3

GND

A

4

FLAG

5

JAM

6

V

CCD

7

V

CCA

8

GND

D

9

TTL

10 11

OUT

(TTL)

OUT

IN

C

OUT

IN

NE5214

OUT

IN

R

HYST

R

PKDET

1B

1A

AZP

AZN

1B

8B

1A

8A

R2

220

L2

10µH

C10

µF

10

C12

L3

10µH

10µF

NOTE: The NE5210/NE5217 combination can operate at data rates in excess of 100Mb/s NRZ The capacitor C7 decreases the NE5210 bandwidth to improve overall S/N ratio in the DC–50MHz band, but does create extra high frequency noise

on the NE5210 V

.01µF

C4

.01µF

10µH

C7

20

100pF

19

C8

18

17

0.1µF

16

15

14

13

12

GND

9

GND

10

GND

11

OUT

12

13

GND

OUT

14

R4 4k

V

NE5210

GND

CC

NC

I

IN

NC

78

6

5

4

3

2

1

Figure 14. A 50Mb/s Fiber Optic Receiver

L1

10µF

R1 100

C3

1.0µF

.01µF

BPF31

OPTICAL

INPUT

SD00330

C5

C6

1998 Oct 07

16

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

GND 2

INPUT

NC

1

GND 2

2

3

4

5

14

OUT (–)

13

GND 2

12

OUT (+)

GND 1

11

10

GND 1

VCC1

6

ECN No.: 06027 1992 Mar 13

VCC 2

78

Figure 15. SA5211 Bonding Diagram

Die Sales Disclaimer

Due to the limitations in testing high frequency and other parameters at the die level, and the fact that die electrical characteristics may shift after packaging, die electrical parameters are not specified and die are not guaranteed to meet electrical characteristics (including temperature range) as noted in this data sheet which is intended only to specify electrical characteristics for a packaged device.

All die are 100% functional with various parametrics tested at the wafer level, at room temperature only (25°C), and are guaranteed to be 100% functional as a result of electrical testing to the point of wafer sawing only. Although the most modern processes are utilized for wafer sawing and die pick and place into waffle pack

1998 Oct 07

GND 1

9

GND 1

SD00488

carriers, it is impossible to guarantee 100% functionality through this process. There is no post waffle pack testing performed on individual die.

Since Philips Semiconductors has no control of third party procedures in the handling or packaging of die, Philips Semiconductors assumes no liability for device functionality or performance of the die or systems on any die sales.

Although Philips Semiconductors typically realizes a yield of 85% after assembling die into their respective packages, with care customers should achieve a similar yield. However, for the reasons stated above, Philips Semiconductors cannot guarantee this or any other yield on any die sales.

17

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

SO14: plastic small outline package; 14 leads; body width 3.9 mm SOT108-1

1998 Oct 07

18

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

NOTES

1998 Oct 07

19

Philips Semiconductors Product specification

SA521 1Transimpedance amplifier (180MHz)

Data sheet status

Objective specification

Preliminary specification

Product specification

Product status

Development

Qualification

Production

Definition

This data sheet contains the design target or goal specifications for product development. Specification may change in any manner without notice.

This data sheet contains preliminary data, and supplementary data will be published at a later date. Philips Semiconductors reserves the right to make chages at any time without notice in order to improve design and supply the best possible product.

This data sheet contains final specifications. Philips Semiconductors reserves the right to make changes at any time without notice in order to improve design and supply the best possible product.

[1]

[1] Please consult the most recently issued datasheet before initiating or completing a design.

Definitions

Short-form specification — The data in a short-form specification is extracted from a full data sheet with the same type number and title. For

detailed information see the relevant data sheet or data handbook. Limiting values definition — Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 134). Stress above one

or more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation of the device at these or at any other conditions above those given in the Characteristics sections of the specification is not implied. Exposure to limiting values for extended periods may affect device reliability.

Application information — Applications that are described herein for any of these products are for illustrative purposes only. Philips Semiconductors make no representation or warranty that such applications will be suitable for the specified use without further testing or modification.

Disclaimers

Life support — These products are not designed for use in life support appliances, devices or systems where malfunction of these products can

reasonably be expected to result in personal injury . Philips Semiconductors customers using or selling these products for use in such applications do so at their own risk and agree to fully indemnify Philips Semiconductors for any damages resulting from such application.

Right to make changes — Philips Semiconductors reserves the right to make changes, without notice, in the products, including circuits, standard cells, and/or software, described or contained herein in order to improve design and/or performance. Philips Semiconductors assumes no responsibility or liability for the use of any of these products, conveys no license or title under any patent, copyright, or mask work right to these products, and makes no representations or warranties that these products are free from patent, copyright, or mask work right infringement, unless otherwise specified.

Philips Semiconductors 811 East Arques Avenue P.O. Box 3409 Sunnyvale, California 94088–3409 Telephone 800-234-7381

 Copyright Philips Electronics North America Corporation 1998

Date of release: 10-98

Document order number: 9397 750 04624

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1998 Oct 07

20

Datasheet SA5211D Datasheet (Philips)

Specifications and Main Features

Frequently Asked Questions

User Manual