Philips
Semiconductors
SA5214
Postamplifier with link status indicator
Product specification
Replaces datasheet NE/SA5214 of 1995 Apr 26
IC19 Data Handbook
1998 Oct 07
INTEGRATED CIRCUITS
Philips Semiconductors
Product specification
SA5214
Postamplifier with link status indicator
2
1998 Oct 07
853-1657 20142
DESCRIPTION
The SA5214 is a 75MHz postamplifier system designed to accept
low level high-speed signals. These signals are converted into a
TTL level at the output. The SA5214 can be DC coupled with the
previous transimpedance stage using SA5210, SA5211 or SA5212
transimpedance amplifiers. This “system on a chip” features an
auto-zeroed first stage with noise shaping, a symmetrical limiting
second stage, and a matched rise/fall time TTL output buffer. The
system is user-configurable to provide noise filtering, adjustable
input thresholds and hysteresis. The threshold capability allows the
user to maximize signal-to-noise ratio, insuring a low Bit Error Rate
(BER). An Auto-Zero loop can be used to minimize the number of
external coupling capacitors to one. A signal absent flag indicates
when signals are below threshold. Additionally, the low signal
condition forces the overall TTL output to a logical Low level. User
interaction with this “jamming” system is available. The SA5214 is
packaged in a standard 20-pin surface-mount package and typically
consumes 42mA from a standard 5V supply. The SA5214 is
designed as a companion to the SA5211/5212 transimpedance
amplifiers. These differential preamplifiers may be directly coupled
to the post-amplifier inputs. The SA5212/5214 or SA5211/5214
combinations convert nanoamps of photodetector current into
standard digital TTL levels.
APPLICATIONS
•
Fiber optics
•
Communication links in Industrial and/or Telecom environment
with high EMI/RFI
•
Local Area Networks (LAN)
•
Metropolitan Area Networks (MAN)
•
Synchronous Optical Networks (SONET)
•
RF limiter
PIN CONFIGURATION
GNDA
GNDD
THRESH
IN1B
JAM
VCCD
VCCA
RPKDET
RHYST
OUT1A
D
1
Package
TOP VIEW
1
2
3
4
5
6
7
8
9
10
11
12
13
14
20
19
18
17
16
15
VOUT
FLAG
LED
CPKDET
IN1A
CAZP
CAZN
OUT1B
IN2B
IN2A
NOTE:
1. SOL – Released in large SO package only.
SD00349
Figure 1. Pin Configuration
FEATURES
•
Postamp for the SA5211/5212 preamplifier family
•
Wideband operation: typical 75MHz (100MBaud NRZ)
•
Interstage filtering/equalization possible
•
Single 5V supply
•
Low signal flag
•
Low signal output disable
•
Link status threshold and hysteresis programmable
•
LED driver (normally ON with above threshold signal)
•
Fully differential for excellent PSRR
•
Auto-zero loop for DC offset cancellation
•
2kV ElectroStatic Discharge (ESD) protection
ORDERING INFORMATION
DESCRIPTION
TEMPERATURE RANGE
ORDER CODE
DWG #
20-Pin Plastic Small Outline Large (SOL) Package
-40
°
C to +85
°
C
SA5214D
SOT163-1
ABSOLUTE MAXIMUM RATINGS
SYMBOL
PARAMETER
RATING
UNIT
V
CCA
Power supply
+6
V
V
CCD
Power supply
+6
V
T
A
Operating ambient temperature range
-40 to +85
°
C
T
J
Operating junction temperature range
-55 to +150
°
C
T
STG
Storage temperature range
-65 to +150
°
C
P
D
Power dissipation
300
mW
V
IJ
Jam input voltage
-0.5 to 5.5
V
Philips Semiconductors
Product specification
SA5214
Postamplifier with link status indicator
1998 Oct 07
3
PIN DESCRIPTIONS
PIN
NO.
SYMBOL
DESCRIPTION
1
LED
Output for the LED driver. Open collector output transistor with 125
Ω
series limiting resistor. An above threshold signal
turns this transistor ON.
2
C
PKDET
Capacitor for the peak detector. The value of this capacitor determines the detector response time to the signal,
supplementing the internal 10pF capacitor.
3
THRESH
Peak detector threshold resistor. The value of this resistor determines the threshold level of the peak detector.
4
GND
A
Device analog ground pin.
5
FLAG
Peak detector digital output. When this output is LOW, there is data present above the threshold. This pin is normally
connected to the JAM pin and has a TTL fanout of two.
6
JAM
Input to inhibit data flow. Sending the pin HIGH forces TTL DATA OUT ON, Pin 10, LOW. This pin is normally connected
to the FLAG pin and is TTL-compatible.
7
V
CCD
Power supply pin for the digital portion of the chip.
8
V
CCA
Power supply pin for the analog portion of the chip.
9
GND
D
Device digital ground pin.
10
V
OUT
TTL output pin with a fanout of five.
11
R
PKDET
Peak detector current resistor. The value of this resistor determines the amount of discharge current available to the
peak detector capacitor, C
PKDET
.
12
R
HYST
Peak detector hysteresis resistor. The value of this resistor determines the amount of hysteresis in the peak detector.
13
IN
2A
Non-inverting input to amplifier A2.
14
OUT
1A
Non-inverting output of amplifier A1.
15
IN
2B
Inverting input to amplifier A2.
16
OUT
1B
Inverting output of amplifier A1.
17
C
AZN
Auto-Zero capacitor pin (Negative terminal). The value of this capacitor determines the low-end frequency response of
the preamp A1.
18
C
AZP
Auto-Zero capacitor pin (Positive terminal). The value of this capacitor determines the low-end frequency response of the
preamp A1.
19
IN
1A
Non-inverting input of the preamp A1.
20
IN
1B
Inverting input of the preamp A1.
BLOCK DIAGRAM
RPKDET
20
19
18
17
16 15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
A1
A2
A3
A4
A5
A6
A7
GATED AMP
OUTPUT BUFFER
OUTPUT DISABLE
PEAK DETECT
LED DRIVER
HYSTERESIS
VCCA
VCCD
OUT1A
OUT1B
A8
IN2B
IN2A
VOUT
JAM
FLAG
LED
IN1B
IN1A
CAZP
CAZN
GNDA
GNDD
THRESH
CPKDET
RHYST
SD00350
Figure 2. Block Diagram
Philips Semiconductors
Product specification
SA5214
Postamplifier with link status indicator
1998 Oct 07
4
RECOMMENDED OPERATING CONDITIONS
SYMBOL
PARAMETER
RATING
UNIT
V
CCA
Supply voltage
4.75 to 5.25
V
V
CCD
Power supply
4.75 to 5.25
V
T
A
Ambient temperature range
-40 to +85
°
C
T
J
Operating junction temperature range
-40 to +110
°
C
P
D
Power dissipation
250
mW
DC ELECTRICAL CHARACTERISTICS
Min and Max limits apply over the operating temperature range at V
CCA
=V
CCD
=+5.0V unless otherwise specified. Typical data applies at
V
CCA
=V
CCD
=+5.0V and T
A
=25
°
C.
SYMBOL
PARAMETER
TEST CONDITIONS
LIMITS
UNIT
SYMBOL
PARAMETER
TEST CONDITIONS
Min
Typ
Max
UNIT
I
CCA
Analog supply current
30
41.2
mA
I
CCD
Digital supply current
(TTL, Flag, LED)
10
13.5
mA
V
I1
A1 input bias voltage
(+/- inputs)
3.08
3.4
3.70
V
V
O1
A1 output bias voltage
(+/- outputs)
3.10
3.8
4.50
V
A
V1
A1 DC gain
(without Auto-Zero)
30
dB
A1
PSRR
A1 PSRR (v
CCA
, V
CCD
)
V
CCA
=V
CCD
=4.75 to 5.25V
60
dB
A1
CMRR
A1 CMRR
∆
V
CM
=200mV
60
dB
V
I2
A2 input bias voltage
(+/- inputs)
3.56
3.7
3.86
V
V
OH
High-level TTL output voltage
I
OH
=-200
µ
A
2.4
3.4
V
V
OL
Low-level TTL output voltage
I
OL
=8mA
0.3
0.4
V
I
OH
High-level TTL output current
V
OUT
=2.4V
-40
-24.4
mA
I
OL
Low-level TTL output current
V
OUT
=0.4V
7.0
30
mA
I
OS
Short-circuit TTL output current
V
OUT
=0.0V
-95
mA
V
THRESH
Threshold bias voltage
Pin 3 Open
0.75
V
V
RPKDET
RPKDET
Pin 11 Open
0.72
V
V
RHYST
RHYST bias voltage
Pin 12 Open
0.72
V
V
IHJ
High-level jam input voltage
2.0
V
V
ILJ
Low-level jam input voltage
0.8
V
I
IHJ
High-level jam input current
V
IJ
=2.7V
30
µ
A
I
ILJ
Low-level jam input current
V
IJ
=0.4V
-485
-240
µ
A
V
OHF
High-level flag output voltage
I
OH
=-80
µ
A
2.4
3.8
V
V
OLF
Low-level flag output voltage
I
OL
=3.2mA
0.33
0.4
V
I
OHF
High-level flag output current
V
OUT
=2.4V
-18
-5
mA
I
OLF
Low-level flag output current
V
OUT
=0.4V
3.25
10
mA
I
SCF
Short-circuit flag output current
V
OUT
=0.0V
-61
-40
-26
mA
I
LEDH
LED ON maximum sink current
V
LED
=3.0V
8
22
80
mA
Philips Semiconductors
Product specification
SA5214
Postamplifier with link status indicator
1998 Oct 07
5
AC ELECTRICAL CHARACTERISTICS
Min and Max limits apply over the operating temperature range at V
CCA
= V
CCD
= +5.0V unless otherwise specified. Typical data applies at
V
CCA
= V
CCD
= +5.0V and T
A
= 25
°
C.
SYMBOL
PARAMETER
TEST CONDITIONS
LIMITS
UNIT
SYMBOL
PARAMETER
TEST CONDITIONS
Min
Typ
Max
UNIT
f
OP
Maximum operating frequency
Test circuit
60
75
MHz
BW
A1
Small signal bandwidth (differential
OUT
1
/IN
1
)
Test circuit
75
MHz
V
INH
Maximum Functional A1
input signal (single ended)
Test Circuit
1.6
V
P-P
V
INL
Minimum Functional A1
input signal (single ended)
Test CIrcuit
1
12
mV
P-P
R
IN1
Input resistance
(differential at IN
1
)
1200
Ω
C
IN1
Input capacitance (differential at IN
1
)
2
pF
R
IN2
Input resistance
(differential at IN
2
)
1200
Ω
C
IN2
Input capacitance (differential at IN
2
)
2
pF
R
OUT1
Output resistance (differential at OUT
1
)
25
Ω
C
OUT1
Output capacitance (differential at
OUT
1
)
2
pF
V
HYS
Hysteresis voltage
Test circuit
3
mV
P-P
V
THR
Threshold voltage range (FLAG ON)
Test circuit, @ 50MHz R
RHYST
=5k
R
THRESH
=47k
12
mV
P-P
t
TLH
TTL Output Rise Time
20% to 80%
Test Circuit
1.3
ns
t
THL
TTL Output Fall Time
80% to 20%
Test Circuit
1.2
ns
t
RFD
t
TLH
/t
THL
mismatch
0.1
ns
t
PWD
Pulse width distortion of output
50mV
P-P
, 1010. . .input
Distortion=
T
H
-T
L
10
2
T
H
+T
L
2.5
2.5
%
NOTES:
1. The SA5214 is capable of detecting a much lower input level. Operation under 12mV
P-P
cannot be guaranteed by present day automatic
testers.
Philips Semiconductors
Product specification
SA5214
Postamplifier with link status indicator
1998 Oct 07
6
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
NE5214
LED
THRESH
FLAG
JAM
125
47k
15pF
400
10k
5k
25
50
VCC
+5V
VIN
VOUT
VOUT
GNDD
VCCA
VCCD
GNDA
CPKDET
IN1B
IN1A
CAZP
CAZN
OUT1B
IN2B
OUT1A
IN2A
RHYST
RPKDET
0.1
µ
F
0.1
µ
F
0.1
µ
F
0.1
µ
F
0.1
µ
F
10
µ
F
100
µ
H
100
µ
H
SD00351
Figure 3. AC Test Circuit
TYPICAL PERFORMANCE CHARACTERISTICS
Analog Supply Current vs Temperature
Digital Supply Current vs Temperature
Threshold Voltage vs R
THRESH
Hysteresis Voltage vs R
HYST
–60
–40
–20
0
20
40
60
80
100
120
36
34
32
30
28
26
24
ANALOG
SUPPL
Y
CURRENT (mA)
VCC = 5.25V
VCC = 5.00V
VCC = 4.75V
TEMPERATURE (
°
C)
–60
–40
–20
0
20
40
60
80
100
120
12.0
11.5
11.0
10.5
10.0
9.5
9.0
DIGIT
AL
SUPPL
Y
CURRENT (mA)
VCC = 5.25V
VCC = 5.00V
VCC = 4.75V
TEMPERATURE (
°
C)
20
30
40
50
22
THRESHOLD (mVp–p)
RHYST = 5k
RTHRESH (k
Ω
)
21
20
19
18
17
16
15
14
13
12
RTHRESH = 47
Ω
HYSTERSIS (mVp–p)
4
3
2
1
0
3
4
5
6
7
RHYST (k
Ω
)
SD00352
Figure 4. Typical Performance Characteristics
Philips Semiconductors
Product specification
SA5214
Postamplifier with link status indicator
1998 Oct 07
7
NOTE:
The NE5211/NE5214 combination can operate at data rates in excess of 100Mb/s NRZ.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
1
2
3
4
5
6
7
8
9
10
11
12
13
14
LED
CPKDET
THRESH
GNDA
FLAG
JAM
VCCD
VCCA
GNDD
TTLOUT
IN1B
IN1A
CAZP
CAZN
OUT1B
IN2B
OUT1A
IN2A
RHYST
RPKDET
NE5214
GND
GND
GND
OUT
GND
GND
OUT
VCC
VCC
NC
IIN
NC
GND
GND
NE521
1
R2
220
D1
LED
C9
100pF
100pF
C7
.01
µ
F
47
µ
F
C1
C2
GND
+VCC
0.1
µ
F
R4
5.1k
R3
47k
VOUT (TTL)
L3
10
µ
H
L2
10
µ
H
C11
C10
.01
µ
F
.01
µ
F
C13
C12
10
µ
F
10
µ
F
C8
L1
10
µ
H
BPF31
OPTICAL
INPUT
R1
100
C5
1.0
µ
F
C6
.01
µ
F
.01
µ
F
C4
10
µ
F
C3
SD00353
Figure 5. A 50Mb/s Fiber Optic Receiver
THEORY OF OPERATION AND APPLICATION
INFORMATION
The SA5214 postamplifier system is a highly integrated chip that
provides up to 60dB of gain at 60MHz, to bring mV level signals up
to TTL levels.
The SA5214 contains eight amplifier blocks (see Block Diagram).
The main signal path is made up of a cascade of limiting stages: A1,
A2 and A8. The A3-A4-A7 path performs a wideband full-wave
rectification of the input signal with adjustable hysteresis and decay
times. It outputs a TTL HIGH on the “FLAG” output (Pin 5) when the
input is below a user adjustable threshold. An on-chip LED driver
turns the external LED to the ON state when the input signal is
above the threshold. In a typical application the “FLAG” output is tied
back to the “JAM” input; this forces the TTL data OUT into a LOW
state when no signal is present at the input.
An auto zero loop allows the SA5214 to be directly connected to a
transimpedance amplifier such as the SA5210, SA5211, or SA5212
without coupling capacitors. This auto-zero loop cancels the
transimpedance amplifier’s DC offset, the SA5214 A1 offset, and the
data-dependent offset in the PIN diode/transimpedance amplifier
combination. For more information on the SA5214 Theory of
Operation, please refer to paper titled “A Low Cost 100 MBaud
Fiber-Optic Receiver” by W. Mack et al.
A typical application of the SA5214 postamplifier is depicted in
Figure 5. The system uses the SA5211 transimpedance amplifier
which has a 28k differential transimpedance gain and a -3dB
bandwidth of 140MHz. This typical application is optimized for a 50
Mb/s Non Return to Zero (NRZ) bit stream.
As the system’s gain bandwidth product is very high, it is crucial to
employ good RF design and printed circuit board layout techniques
to prevent the system from becoming unstable.
For more information on this application, please refer to AB 1432.
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.
Philips Semiconductors
Product specification
SA5214
Postamplifier with link status indicator
1998 Oct 07
8
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
carriers, it is impossible to guarantee 100% functionality through this
process. There is no post waffle pack testing performed on
individual die.