PHILIPS NE83Q93N Enhanced coaxial ethernet transceiver Datasheet

Philips Semiconductors
Product specification
Enhanced coaxial Ethernet transceiver
DESCRIPTION
NE83Q93
PIN CONFIGURATION
The NE83Q93 is a low power coaxial transceiver interface (CTI) for
Ethernet (10base5) and Thin Ethernet (10base2) local area
networks. The CTI is connected between the coaxial cable and the
Data Terminal Equipment (DTE) and consists of a receiver,
transmitter, receive-mode collision detector, heartbeat generator and
jabber timer (see Block Diagram). The transmitter output connects
directly to a doubly terminated 50Ω cable, while the receiver output,
collision detector output and transmitter input are connected to the
DTE through isolation transformers. Isolation between the CTI and
the DTE is an IEEE 802.3 requirement that can be met on signal
lines by using a set of pulse transformers. Power isolation for the
CTI is achieved using DC-to-DC conversion through a power
transformer (see Figure 1, Connection Diagram).
D, N Packages
The part is functionally the same as the NE83Q92, but with
additional features such as a transmit enable input, a carrier detect
output and five status LED driver outputs.
The NE83Q93 is manufactured on an advanced BiCMOS process
and is available in an SOL package making it ideally suited to
lap-top personal computers or systems where low power
consumption, limited board space and jumperless design is
required. Refer to selection flow chart for optimal application.
CD+
1
24 CDS
CD–
2
23 TXO
RX+
3
22 RXI
VEE
4
21 VEE
VEE
5
20 RR–
RX–
6
19 RR+
TX+
7
18 GND
TX–
8
17 HBE
TEN
9
16 CRS
XLED
10
15 RLED
JLED
11
14 LINK
LCOM
12
13 CLED
SD00311
• Smart squelch on data inputs eliminates false activations
• Transmit enable input and carrier sense output for repeater
FEATURES
• Fully compliant with Ethernet II, IEEE 802.3 10BASE-5 and
10BASE-2, and ISO 8802/3 interface specifications
applications
• Functionally compatible with industry standard 8392 applications
• Optimal implementation can use 1 Watt DC-DC converter and
• Five LED status drivers for transmit, receive, collision, jabber and
link fail indication
reduces external parts count
• Advanced BiCMOS process for extremely low power operation
• Available in 24-pin DIP and 24-pin SOL packages
• Full ESD protection
• Power-on reset prevents glitches on coaxial cable
• High efficiency AUI drivers minimize current consumption under
idle conditions by automatically powering-down
• Automatically disables AUI drivers when disconnecting coax
cable, allowing hard-wiring of AUI connector and local/integrated
CTI connection
ORDERING INFORMATION
DESCRIPTION
TEMPERATURE RANGE
ORDER CODE
DWG #
24-Pin Plastic Dual In-Line Package (DIP)
0 to +70°C
NE83Q93N
0410D
24-Pin Plastic Small Outline Large (SOL) Package
0 to +70°C
NE83Q93D
SOT137-1
1995 May 1
1
853-1738 15180
Philips Semiconductors
Product specification
Enhanced coaxial Ethernet transceiver
NE83Q93
PIN DESCRIPTIONS
PIN NO.
D, N PKG
SYMBOL
DESCRIPTION
1
2
CD+
CD–
Collision Outputs. Balanced differential line driver outputs which send a 10MHz signal to the DTE in the event of
a collision, jabber interrupt or heartbeat test. External pull-down resistors are optional.
3
6
RX+
RX–
Receiver Outputs. Balanced differential line driver outputs which send the received signal to the DTE. External
pull-down resistors are optional.
7
8
TX+
TX–
Transmitter Inputs. Balanced differential line receiver inputs which accept the transmission signal from the DTE
and apply it to the coaxial cable at TXO, if it meets Tx squelch threshold.
9
TEN
Transmit Enable. A CMOS compatible input requiring an input voltage range of VEE to VEE + 5V. The transmitter
and loopback functions are disabled when TEN is LOW and enabled when TEN is HIGH or left floating. TEN is
normally driven through an opto-coupler.
10
XLED
Transmit Indicator. Indicates a packet is being transmitted onto the coaxial cable.
11
JLED
Jabber Indicator. Indicates that the jabber timer has timed out and the coaxial driver is disabled.
12
LCOM
LED Common. The anodes of all status indicator LEDs are connected to this pin. It’s voltage is VEE + 5V.
13
CLED
Collision Indicator. Indicates that a collision has been detected.
14
LINK
Link Indicator. Indicates that a connection is present to the coaxial cable network.
15
RLED
Receive Indicator. Indicates that a packet is being received from the coaxial cable.
16
CRS
Carrier Sense. A real time output that indicates the presence of a carrier on the coaxial cable. CRS is normally
used to drive an opto-coupler.
17
HBE
Heartbeat Enable. The heartbeat function is disabled when this pin is connected to VEE and enabled when
connected to GND or left floating.
11
12
RR+
RR–
External Resistor. A 1kΩ (1%) resistor connected between these pins establishes the signaling current at TXO.
22
RXI
Receiver Input. This pin is connected directly to the coaxial cable. Received signals are equalized, amplified,
and sent to the DTE through the RX+ pins, if it meets Rx squelch threshold.
23
TXO
Transmitter Output. This pin is connected directly (Thin Ethernet) or through an external isolating diode
(Ethernet) to the coaxial cable.
24
CDS
Collision Detect Sense. Ground sense connection for the collision detection circuitry. This pin should be
connected directly to the coaxial cable shield for standard Ethernet operation.
18
GND
Positive Supply Pin.
4
5
21
VEE
Negative supply pins.
NOTE:
1. The IEEE 802.3 name for CD is CI; for RX is DI; for TX is DO.
1995 May 1
2
Philips Semiconductors
Product specification
Enhanced coaxial Ethernet transceiver
NE83Q93
BLOCK DIAGRAM
DTE
INTERFACE
COAX
CABLE
RXI
BUFFER
LINE
DRIVER
RECEIVE
PAIR
(RX+, RX–)
RECEIVER
EQUALIZER
4–POLE BESSEL
LOW PASS FILTER
CARRIER
SENSE
(CRS)
RECEIVER
SQUELCH
TXO
TRANSMIT
PAIR
(TX+, TX–)
TRANSMITTER
CDS
SENSE
BUFFER
TEN
LINK
STATUS
CONTROL
TRANSMITTER
SQUELCH
COLLISION
(CLED)
JABBER
(JLED)
XLED
RLED
COLLISION
COMPARATOR
&
HEARTBEAT
GENERATOR
HBE
LCOM
COLLISION
PAIR
(CD+, CD–)
10MHz
OSC
JABBER
TIMER
LINE
DRIVER
SD00312
ABSOLUTE MAXIMUM RATINGS
SYMBOL
VEE
PARAMETER
Supply voltage1
input1
VIN
Voltage at any
TSTG
Storage temperature range
TSOLD
Lead soldering temperature (10sec.)
temperature2
TJ
Recommended max junction
θJA
Thermal impedance (N and A packages)
NOTE:
1. 100% measured in production.
2. The junction temperature is calculated from the following expression:
TJ = TA + θJA [(VEE x 0.015 x nIDL) + (VEE x 0.027 x nRX) + (VEE x 0.075 x nTX)]
where
TA = Ambient temperature in °C.
θJA = Thermal resistance of package.
VEE = Normal operating supply voltage in volts.
nIDL = Percentage of duty cycle idle
nRX = Percentage of duty cycle receiving
nTX = Percentage of duty cycle transmitting
1995 May 1
3
RATING
UNIT
–12
V
0 to –12
V
–65 to +150
°C
+300
°C
+150
°C
60
°C/W
Philips Semiconductors
Product specification
Enhanced coaxial Ethernet transceiver
NE83Q93
ELECTRICAL CHARACTERISTICS
VEE = –9V ±6%; TA = 0°C to +70°C unless otherwise specified1,2. No external isolation.
LIMITS
SYMBOL
VUVL
PARAMETER
TEST CONDITIONS
MIN
Under voltage lockout. Transceiver disabled for
|VEE| < |VUVL|
Supply current transmitting (without collision)
Without external
pull-down resistors and
no LED loads
IRXI
Receive input bias current
VRXI = 0V
ICDS
Cable sense input bias current
VCDS = 0V
VIH
HBE input HIGH voltage
VIL
HBE input LOW voltage
IIH
HBE input HIGH current
VHBE = 0V
IIL
HBE input LOW current
VHBE = VEE
–20
mA
–80
–90
mA
+25
µA
+3
µA
–2
+1
V
VEE + 2
Input LOW voltage at TEN
VEE + 1
ITENL
Input LOW current at TEN
–50
ITDC
Transmit output DC current level3
ITAC
Transmit output AC current level3
ITX10
Transmit current
VDIS
AUI disable voltage at RXI
VOD
Differential output voltage – non idle at RX+ and
CD±6
VOB
Differential output voltage imbalance – idle at
RX± and CD±7
VOC
Output common mode voltage at RX± and CD±
VRS
Receiver squelch threshold
VTS
Transmitter squelch threshold
RRXI
Shunt resistance at RXI non–transmitting
CRXI
Input capacitance at RXI8
RTXO
Shunt resistance at TXO transmitting
RAUIZ
RTX
µA
V
V
–100
µA
–37
–45
mA
±28
±ITDC
mA
–250
+250
µA
–3.7
V
–1580
mV
Transmitter output voltage compliance4
Collision threshold5
V
+10
µA
Input HIGH voltage at TEN
Measured by applying
DC voltage at RXI
(CDS = 0V)
VEE +1.6
–30
VTENL
VCD
V
VEE +2.4
VTXO = –10V
UNIT
–15
VTENH
VTCOM
MAX
–7.5
Supply current idle
IEE
TYP
–1450
Measured as DC
voltage at RXI
–1530
–3.5
±600
V
±1100
mV
±40
mV
RXI = 0V
–4.0
–5.5
–7.0
V
VRXI average DC
(CDS = 0V)
–150
–250
–350
mV
(VTX+ – VTX–) peak
–175
–225
–275
mV
1
2
100
7.5
kΩ
pF
10
kΩ
Differential impedance at RX± and CD± with no
coaxial cable connected
6
kΩ
Differential impedance at TX±
20
kΩ
LED driver and CRS output
VOL
Output LOW voltage
IOL
Output leakage current inactive
IOUT = 8mA
VEE +1.4
V
VEE < VOUT < VEE + 5
10
µA
NOTES:
1. Currents flowing into device pins are positive. All voltages are referenced to ground unless otherwise specified. For ease of interpretation,
the parameter limit that appears in the MAX column is the largest value of the parameter, irrespective of sign. Similarly, the value in the MIN
column is the smallest value of the parameter, irrespective of sign.
2. All typicals are for VEE = –9V and TA = 27°C.
3. ITDC is measured as (VMAX + VMIN)/(2 x 25) where VMAX and VMIN are the max and min voltages at TXO with a 25Ω load between TXO and
GND. ITAC is measured as (VMAX – VMIN)/(2 x 25).
4. The TXO pin shall continue to sink at least ITDC min when the idle (no signal) voltage on this pin is –3.7V.
5. Collision threshold for an AC signal is within 5% of VCD.
6. Measured on secondary side of isolation transformer (see Connection Diagram, Figure 1). The transformer has a 1:1 turns ratio with an
inductance between 30 and 100µH at 5MHz.
7. Measured as the voltage difference between the RX pins or the CD pins with the transformer removed.
8. Not 100% tested in production.
1995 May 1
4
Philips Semiconductors
Product specification
Enhanced coaxial Ethernet transceiver
NE83Q93
TIMING CHARACTERISTICS
VEE = –9V +6%; TA = 0 to 70°C, unless otherwise specified1. No external isolation diode on TXO.
LIMITS
SYMBOL
PARAMETER
TEST CONDITIONS
tRON
Receiver start up delay RXI to RX± (Figure 4)
First received bit on RX±
MIN
TYP
MAX
UNIT
VRXI = –2V peak
3
5
bits
tRON +2
bits
VRXI = –2V peak
20
50
ns
First validly timed bit on RX±
tRD
Receiver prop. delay RXI to RX±
tRR
Differential output rise time on RX± and CD±2,3
5
7
ns
tRF
Differential output fall time on RX± and C±2,3
5
7
ns
tOS
Differential output settling time on RX± and CD±
to VOB = 40mV2 (see Figure 5)
1
tRJ
Receiver and cable total jitter
tRHI
Receiver high to idle time
tRM
Rise and fall time matching on RX+ and CD+
tTST
Transmitter start–up delay TX± to TXO (Fig. 6)
First transmitted bit on TXO
±2
Measured to +210mV
200
Transmitter prop delay TX± to TXO
(see Figure 6)
tTR
tTF
tTM
tTS
±6
ns
850
ns
tRF – tRR
0.1
±2
ns
VTX+ = –1V peak
1
2
bits
tTST + 2
bits
First validly timed bit
tTD
µs
VTX+ = 1V peak
5
20
50
ns
Transmitter rise time 10% to 90% (see Figure 6)
20
25
30
ns
Transmitter fall time 10% to 90% (see Figure 6)
20
25
30
ns
tTF – tTR mismatch5
0
±2
ns
Transmitter added skew4,5
0
±2
ns
tTON
Transmitter turn on pulse width (see Figure 6)
VTX± = 1V peak
10
35
ns
tTOFF
Transmitter turn off pulse width (see Figure 6)
VTX+ = 1V peak
125
200
ns
tCON
Collision turn on delay (see Figure 7)
0V to –2V step at RXI
13
bits
tCOFF
Collision turn off delay (see Figure 7)
–2V to 0V step at RXI
16
bits
tCHI
Collision high to idle time (see Figure 7)
Measured to +210mV
fCD
Collision frequency (see Figure 7)
tCP
200
8.5
10
850
ns
11.5
MHz
Collision signal pulse width (see Figure 7)
35
70
ns
tHON
Heartbeat turn on delay (see Figure 8)
0.6
1.6
µs
tHW
Heartbeat test duration (see Figure 8)
0.5
1.5
µs
tJA
Jabber activation delay measured from TX± to
CD± (see Figure 9)
20
60
ms
tJR
Jabber reset delay measured from TX± to CD±
(see Figure 9)
250
650
ms
LEDs
tLED
10
µs
135
ms
7
10
ms
115
135
ms
10
ms
18
ms
Turn-on or turn-off delay of LEDs
tXLEDON
XLED maximum on time
90
tXLEDOFF
XLED minimum off time
5
tRLEDON
RLED maximum on time
90
tRLEDOFF
RLED minimum off time
5
tCLEDON
CLED minimum on time
10
tJLEDON
JLED maximum on time
tJLEDOFF
JLED minimum off time
115
14
NOTES:
1. All typicals are for VEE = –9V and TA = 27°C.
2. Measured on secondary side of isolation transformer (see Figures 1 and 2, Connection Diagram). The transformer has a 1:1 turn ratio with
an inductance between 30 and 100µH at 5MHz.
3. The rise and fall times are measured as the time required for the differential voltage to change from –225mV to +225mV, or +225mV to
–225mV, respectively.
4. Difference in propagation delay between rising and falling edges at TXO.
5. Not 100% tested in production.
1995 May 1
5
Philips Semiconductors
Product specification
Enhanced coaxial Ethernet transceiver
NE83Q93
The differential line driver provides typically +900mV signals to the
DTE with less than 7ns rise and fall times. When in idle state (no
received signal) its outputs provide <20mV differential voltage offset
to minimize DC standing current in the isolation transformer.
FUNCTIONAL DESCRIPTION
The NE83Q93 is a low power BiCMOS coaxial Ethernet transceiver
which complies with the IEEE 802.3 specification and offers a
number of additional features. These features are:
1. Low current consumption of typically 15mA when idle and 80mA
while transmitting without collision allows smaller DC-DC
converter to be used for the isolated power supply (no external
pull-down resistors).
Transmitter Functions
The transmitter has differential inputs and an open collector current
driver output. The differential input common mode voltage is
established by the CTI and should not be altered by external
circuitry. Controlled rise and fall times of 25ns (+5ns) minimize
higher harmonic components in the transmitted spectrum, while
matching of these rise and fall times to typically 2ns minimizes
signal jitter. The drive current levels of the CTI are set by an on-chip
bandgap voltage reference and an external 1% resistor. An on-chip
isolation diode is provided to reduce the transmitter’s coaxial cable
load capacitance. For Thin Ethernet applications, no further external
isolation diode is required, since the NE83Q93 meets the capacitive
loading specifications. For Ethernet applications a further external
diode should be added to reduce loading capacitance.
2. Automatic selection between AUI cable and coaxial connections
by placing the AUI outputs in a high impedance state when the
coaxial cable is disconnected. This eliminates the need for
changing a jumper position on the Ethernet board when selecting
either Thin Ethernet or remote transceiver connections.
3. High efficiency AUI drivers for the RX± and CD± ports
automatically power down when idling and are powered-up when
a receive signal is detected. This is very important/useful for
power sensitive applications such as lap-top computers or
PCMCIA cards.
The transmitter squelch circuit ensures that the transmitter can only
be enabled if the transmitted packet begins with a 01 bit sequence
where the negative-going differential signals are typically greater
than 225mV in magnitude and 25ns in duration.
4. The NE83Q93 advanced AUI driver (RX± and CD±) design
requires no external pull-down resistors (500Ω) to drive a
terminated (78Ω) AUI cable and still meets the IEEE 802.3
specification. The drivers will also operate correctly if external
resistors are present, so that they can be retro-fitted into existing
8392 designs. However, an extra current of 7mA/output (for
500Ω resistors) would be generated, by these resistors,
regardless of whenther the transceiver is idle or responding to
traffic.
The transmitter will be disabled at the end of a packet if there are no
negative going signals of greater than 225mV for more than typically
150ns. Figure 6 illustrates transmitter timing.
Collision Functions
The collision detection scheme implemented in the NE83Q93 is
receive mode detection, which detects a collision between any two
stations on the network with certainty at all times, irrespective of
whether or not the local DTE is producing one of the colliding
signals. This is the only detection scheme allowed by the IEEE
802.3 standard for both repeater and non-repeater nodes.
5. Transmit enable input and carrier sense output for direct use in
repeater applications.
6. LED control circuitry and drivers for indicating the transmit,
receive, collision, jabber and link status of the transceiver unit.
The collision circuitry consists of the 4-pole Bessel low pass filter, a
comparator, a precision voltage reference that sets up the collision
threshold, a heartbeat generator, a 10MHz oscillator, and a
differential line driver.
Receiver Functions
The receiver consists of an input buffer, a cable equalizer, a 4-pole
Bessel low pass filter, a squelch circuit and a differential line driver.
The collision comparator monitors the DC level at the output of the
low pass filter and enables the line driver if it is more negative than
the collision threshold. A collision condition is indicated to the DTE
by a 10MHz oscillation signal at the CD outputs and typically occurs
within 700ns of the onset of the collision. The collision signal begins
with a negative-going pulse and ends with a continuous high-to-idle
state longer than 170ns. Figure 7 illustrates collision timing.
The buffer provides high input resistance and low input capacitance
to minimize loading and reflections on the coaxial cable.
The equalizer is a high pass filter that compensates for the low pass
effect of the coaxial cable and results in a flatband response over all
signal frequencies to minimize signal distortion.
The 4-pole Bessel low pass filter extracts the average DC voltage
level on the coaxial cable for use by the receiver squelch and
collision detection circuits.
At the end of every transmission, the heartbeat generator creates a
pseudo collision to ensure that the collision circuitry is properly
functioning. This pseudo collision consists of a 1µs burst of 10MHz
oscillation at the line driver outputs approximately 1µs after the end
of the transmission. The heartbeat function can be disabled
externally by connecting the HBE (heartbeat enable) to VEE. This
allows the CTI to be used in repeater applications. Figure 8
illustrates heartbeat timing.
The receiver squelch circuit prevents noise on the coaxial cable
from falsely triggering the receiver in the absence of a true signal.
At the beginning of a packet, the receiver turns on when the DC
level from the low pass filter exceeds the DC squelch threshold and
the received packet has started with a 01 bit sequence with
acceptable timing parameters. For normal signal levels this will take
less than 500ns, or 5 bits. However, at the end of a packet, a fast
receiver turn off is needed to reject both dribble bits on the coaxial
cable and spurious responses due to settling of the on-chip
bandpass filter. This is accomplished by an AC timing circuit that
disables the receiver if the signal level on the coaxial cable remains
high for typically 250ns and only enables the receiver again after
approximately .5µs. Figures 4 and 5 illustrate receiver timing.
1995 May 1
Jabber Functions
The jabber timer monitors the transmitter and inhibits transmission if
it is active for longer than typically 30ms. The jabber circuit then
enables the collision outputs for the remainder of the data packet
and for typically 450ns (unjab time) after it has ended. At this point
the transmitter becomes uninhibited. Figure 9 illustrates jabber
timing.
6
Philips Semiconductors
Product specification
Enhanced coaxial Ethernet transceiver
NE83Q93
There is a 400ms collision announcement on disconnecting RXI, but
there is no announcement on re-connection. This feature can be
disabled by pulling RXI up with a 200kΩ to ground.
Control Interface Signals
The NE83Q93 provides two input and one output signal for mode
control and interfacing within repeaters. The output signal is Carrier
Sense (CRS) and the input signals are Heartbeat Enable (HBE) and
Transmit Enable (TEN).
Detection of Coaxial Cable Faults
In the NE83Q93 there is no internal loopback path from the TX
inputs to the RX outputs. This means that, when the local DTE is
transmitting, the signal will only be present at the receiver outputs
RX+ and RX– if it appears on the coaxial cable and is larger than
the receiver squelch threshold VRS. If a short circuit fault condition
occurs at the cable connector to the CTI, then no signal will appear
at the receiver outputs.
The HBE input controls the transmission of the heartbeat (or SQE)
signal to the DTE for testing the collision detection function. It is
normally hardwired to VEE or GND.
1. The heartbeat (SQE) function is DISABLED when HBE is
connected to VEE
2. The heartbeat (SQE) function is ENABLED when HBE is
connected to GND or left floating
In the case of an open circuit at the coaxial cable connector there
will also be no signal at the receiver outputs due to the AUI disabling
mode of the NE83Q93. However, a heartbeat signal will be present
following a transmission attempt for the short circuit condition, but
not for the open circuit.
The TEN input controls the coaxial transmitter. It is a CMOS
compatible input requiring a driving signal with a voltage range of
VEE to VEE + 5V. It is normally driven through an opto-coupler to
provide electrical isolation. A typical application circuit is shown in
Figure 2.
A coaxial cable with only a single 50Ω termination will generate a
collision not only at every transmission attempt, but also for every
reception attempt due to the receive mode collision detection of the
NE83Q93.
1. The coaxial transmitter is DISABLED when a LOW is applied to
TEN or it is directly connected to VEE. Since the loopback
function of the NE83Q93 occurs through the coaxial connection
the loopback function is also disabled.
Status Indicator Functions
The NE83Q93 provides five status outputs, the open drain device
connected to each is capable of directly driving an LED or
opto-coupler, or other logic circuits if an external pull-up resistor is
used. The functional descriptions below are for an LED connected
between the output and LCOM (VEE + 5V) through a current limiting
series resistor.
2. The coaxial transmitter is ENABLED when a HIGH is applied to
TEN or it is directly connected to GND or left floating.
The CRS output indicates the presence of a carrier signal on the
coaxial cable. It is open drain output designed to drive the LED of
an opto-coupler connected between CRS and LCOM through a
current limiting series resistor. A LOW at CRS is VEE and a HIGH is
the voltage at LCOM (VEE + 5V).
The LINK signal indicates the status of the coaxial connection.
• The LED is ON when the transceiver is connected to a properly
terminated coaxial cable.
• The LED is OFF when the coaxial cable is disconnected from the
1. CRS is HIGH (no current) when no carrier is present
transceiver, or if the coaxial connection is unterminated.
The XLED signal indicates the status of the transmitter.
2. CRS is LOW (current sinking) when carrier is present
• The LED is OFF when there is no transmission in progress
• The LED is turned ON when data is being transmitted and
On applying a HIGH to TEN through an opto-coupler the transmitter
is enabled but it still has to recognize the normal squelch-qualified
01 bit sequence with the negative-going differential signals meeting
the necessary magnitude and duration requirements. The set-up
time needed from application of a HIGH at TEN to recognizing the
first 01 bit sequence is typically 25ns. The propagation delay
through an opto-coupler is of the order of 200ns.
remains ON for typically 115ms.
The RLED signal indicates the status of the receiver.
• The LED is OFF when no signal is being received.
• The LED is turned ON when data is received and remains ON for
typically 115ms.
AUI Selection/Under Voltage Lockout
The CLED signal indicates the status of the collision detection
circuit.
The transmit and receive squelch circuits of the NE83Q93 remain
active if the absolute value of VEE is less than the threshold for
under voltage lockout, VUVL. This prevents glitches from appearing
on either the AUI or coaxial cable during power up and power down.
• The LED is OFF for no collision.
• The LED turns ON when a collision is detected and remains ON
for typically 12ms after the end of the collision.
There is no collision announcement during power up and the
transceiver waits for 400ms before becoming enabled.
• In the event of another collision during the latter 6ms of the 12 ms
delay period after the end of the last collision, the LED will turn off
for typically 6ms then back ON to indicate the new collision.
If RXI is disconnected from the coaxial cable after power up, its
voltage will fall towards VEE. If the absolute value of this voltage
exceeds the AUI disable voltage, VDIS, for longer than 800ms, the
transmit and receive squelch circuits remain active and, in addition,
the AUI drivers become high impedance. This permits AUI
connections to be hard wired together, e.g., the coaxial transceiver
and a 10BASE-T transceiver, with the signal path determined by
which transceiver is connected to its external cable.
1995 May 1
The JLED signal indicates the status of the jabber control circuit.
• The LED is OFF for a no-jab condition.
• The LED turns ON when the coaxial transmitter output is jabbed.
• The LED turns back off when the transmitter is unjabbed.
7
Philips Semiconductors
Product specification
Enhanced coaxial Ethernet transceiver
NE83Q93
AUI
CABLE
12 TO 15V DC
+
DC TO DC
CONVERTER
<200mA
9V (ISOLATED)
–
500Ω
1
COLLISION
PAIR
500Ω
500Ω
78Ω
2
DTE
16
(NOTE 4)
500Ω
15
T1 (NOTE 1)
(NOTE 3)
COAX
4
13
CD+
RECEIVE
PAIR
78Ω
1
16
2
15
CD–
5
12
RX+
3
VEE
VEE
7
10
NE83C92
14
4
13
5
12
CTI
6
11
7
10
8
9
TX+
8
9
78Ω
TXO
(NOTE 2)
RXI
VEE
RR–
RX–
TRANSMIT
PAIR
CDS
200kΩ
RR+ 1kΩ 1%
GND
TX–
HBE
(NOTE 5)
NOTES:
1. T1 is a 1:1 pulse transformer, with an inductance of 30 to 100µH.
2. IN916 or equivalent for Ethernet, not required for Thin Ethernet.
3. 78Ω resistors not required if AUI cable is not used, i.e., local transceiver.
4. Typical pull-down resistors are not required for either 10BASE2 or 10BASE5 application. Remove them for minimum current consumption.
5. Install 200kΩ to disable the 400ms collision announcement when disconnecting cable.
SD00313
Figure 1. Connection Diagram for Standard 8392 Applications
1995 May 1
8
Philips Semiconductors
Product specification
Enhanced coaxial Ethernet transceiver
NE83Q93
NE83Q93
+5V
OPTO-ISOLATOR
CTI
+5V
16
LCOM
15
OPTO-ISOLATOR
14
TEN
9
13
TRANSMIT
ENABLE
(TTL/CMOS)
12
CRS
CARRIER
DETECT
(TTL/CMOS)
RLED
LINK
CLED
LCOM
JLED
11
VEE
VEE
10
XLED
SD00314
Figure 2. Control Interface Connections
MAU
COAX
I
S
O
L
A
T
I
O
N
NE83Q93
COAX
TRANSCEIVER
INTERFACE
SERIAL
NETWORK
INTERFACE
(OPTIONAL)
(AUI CABLE)
NETWORK
INTERFACE
CONTROLLER
B
U
S
DTE
MAU = Medium Attachment Unit
AUI Cable = Attachment Unit Interface Cable (not used in Thin Ethernet applications)
SD00315
Figure 3. Interface Diagram for Ethernet/Thin Ethernet Local Area Network
RXI
1
2
3
4
PHASE VIOLATION
ALLOWED
5
6
VALID
TIMING
7
8
9
10
11
tRD
90%
RX+
10%
5
6
7
8
9
tRON+2
tTR
tRON
10
tTF
tRR
11
tRF
SD00306
Figure 4. Receiver Timing
1995 May 1
9
Philips Semiconductors
Product specification
Enhanced coaxial Ethernet transceiver
NE83Q93
RXI
tOS
tRHI
RX+
SD00279
Figure 5. Receiver End–of–Packet Timing
tTST+2
100ns
tTST
tTOFF
TX+
1
2
3
4
5
6
7
tTON
tTD
8
9
10
TXO
11
90%
10%
1
2
3
4
5
6
7
8
9
tTR
10 11
tTF
tRF
tRR
SD00305
Figure 6. Transmitter Timing
RXI
0V
–2V
tCON
tCOFF
tCHI
CD+
1/FCD
tCP
SD00280
Figure 7. Collision Timing
TX+
tHON
tHW
CD+
SD00281
Figure 8. Heartbeat Timing
1995 May 1
10
Philips Semiconductors
Product specification
Enhanced coaxial Ethernet transceiver
NE83Q93
TX+
tJA
tJR
TXO
CD+
SD00282
Figure 9. Jabber Timing
TX,
RX
(LCOM)
XLED,
RLED (V )
EE
TXLEDON
TRLEDON
TXLEDOFF
TRLEDOFF
CD
(COLLISION)
(LCOM)
CLED
TCLEDON
TCLEDON
TCLEDON
(VEE)
CD
(JABBER ON)
(LCOM)
JLED
JABBER
LED ON
(VEE)
LINE
DISCONNECTED
COAX
(LCOM)
LINK
(LED)
(VEE)
LINK
LED OFF
RX
(LCOM)
CRS
(VEE)
SD00510
Figure 10. LED Timing
1995 May 1
11
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