ETC HDMP

Agilent HDMP-1685A
1.25 Gbps Four Channel SerDes
with 5-pin DDR SSTL_2
Parallel Interface
Data Sheet
Functional Description
This data sheet describes HDMP1685A, a 1.25 Gbps, four-channel,
5-pin per channel parallel interface
SERDES device. The HDMP-1685A
5-pin parallel interface device enables a single ASIC to drive twice as
many channels using half as many
parallel lines. This is accomplished
without increasing the clock
frequency by utilizing the bandwidth
on the parallel interface more
efficiently.
The HDMP-1685A SERDES is a
single silicon bipolar integrated
circuit packaged in a 208-pin BGA.
This integrated circuit provides a
low-cost, small-form-factor physicallayer solution for multi-link
1.25 Gbps cables or optical transceivers. Each IC contains transmit
and receive channel circuitry for all
four channels.
A 125 MHz LVTTL reference clock
must be supplied to the reference
clock input pin, RFCT.
The transmitter section accepts
four, 5-bit-wide parallel SSTL_2
data (TX [0:3] [0:4]), a 125 MHz
SSTL_2 byte clock (TC) and serializes them into four high-speed
serial streams. The parallel data
is expected to be “8B/10B” encoded data, or equivalent. TX and
TC are source synchronous. New
data are accepted on both edges
of TC; this is called Double Data
Rate (DDR). HDMP-1685A finds
a sampling window in between
the two edges of TC to latch
TX [0:3] [0:4] data into the input
register of the transmitter section.
This timing scheme assumes that
the driving ASIC and HDMP-1685A
operate in the same clock domain.
8B/10B encoded data comes in
10-bit characters. This data is
latched onto the 5 TX pins of each
channel in 5-bit groups. It is expected that the beginning half of
each 10-bit character is latched on
the rising edge of TC.
Features
• 5-bit wide Tx, Rx bus pairs
• 208-ball, 23 mm TBGA package
• Parallel data I/O and clocks
compatible with SSTL_2
(EIA/JESD8-9)
• 125 MHz TC, RC clocks
• One TC clock for 4 channels
• Single or paired RC clocks
• LVTTL RefClk input
• Source synchronous clocking of
transmit data
• Source centered clocking of
receive data
• Double data rate (DDR) parallel
transfers
• Parallel loopback
• Differential BLL serial I/O
• Single +3.3 V power supply
• Copper drive capability
Applications
• High density fast ports
• Fast serial backplanes
• Clusters of computers
• Clusters of network units
• Link aggregation, trunks
The transmitter section’s PLL
locks to the 125 MHz TC. This
clock is then multiplied by 10 to
generate the 1250 MHz serial
clock for the high-speed serial
outputs. The high-speed outputs
are capable of interfacing directly
to copper cables for electrical
transmission or to a separate fiber
optic module for optical
transmission.
The receiver section accepts four
serial electrical data streams at
1250 MBd and recovers the respective original 10-bit-wide data
for each channel over a 5-pin
parallel interface. The receiver
PLL locks onto the incoming
serial signal and recovers the
high-speed serial clock and data.
The serial data is converted back
into 10-bit parallel data, optionally recognizing the 8B/10B
comma character to establish
byte alignment. If comma character detection is enabled by raising
the SYNC signal high, the receiver section is able to detect
comma characters and indicate
their presence on each channel
with the appropriate SYN [0:3]
signal(s).
The recovered parallel data are
presented at SSTL_2-compatible
outputs RX [0:3] [0:4], and a pair
of 125 MHz SSTL_2 clocks,
RC [0:3] [1], and RC [0:3] [0],
that are 180 degrees out of phase
from one another and which represent the remote clock for that
channel. Rising edges of
RC [0:3] [1] and RC [0:3] [0]
may be used to latch RX data at
the destination. Alternatively,
both edges of either RC [0:3] [1]
or RC [0:3] [0] may be used to
latch RX data (DDR). When SYNC
is high, the beginning half of the
comma character shows up at the
rising edge of
RC [0:3] [1].
The timing of transmit and receive parallel data with respect to
TC and RC [0:3] [0:1] is arranged
so that the upstream protocol
device can generate and latch
data very simply. Specifically, in
the TX direction, the ASIC drives
four sets of 5-pin TX lines and the
TC line with the same timing. The
2
TC line is similar to a 6th data
line that is always toggling to
provide timing information to the
SERDES. On the RX side, the
SERDES drives four sets of 5-pin
RX data centered between the
edges of RC [0:3] [1] or
RC [0:3] [0].
For test purposes, the transceiver
provides for on-chip parallel
loopback functionality controlled
through an input pin. Additionally, the byte-edge alignment
feature via detection of the positive comma (K28.5+) character
may be disabled. This may be
useful in proprietary applications
that use alternative methods to
align the parallel data.
HDMP-1685A Block Diagram
The HDMP-1685A (Figure 2) is
designed to transmit and receive
10-bit 8B/10B character data
over 5-pin-wide parallel busses
via high-speed serial communication lines. The parallel data
applied to the transmitter is
expected to be encoded per the
8B/10B encoding scheme with
special reserve characters for link
management purposes. Other
encoding schemes will also work
as long as they provide dc balance and sufficient number of
transitions. In order to accomplish this task, the HDMP-1685A
incorporates the following:
• SSTL_2 Parallel Data I/O
• High-Speed Phase Locked
Loops
• Parallel-to-Serial Converters
• High-Speed Serial Clock and
Data Recovery Circuitry
• Comma Character Recognition
Circuitry (K28.5+)
• Byte Alignment Circuitry
• Serial-to-Parallel Converter
PARALLEL INPUT LATCH
For each channel, the transmitter
accepts 10-bit characters as two
groups of 5-pin single-ended
SSTL_2 parallel data at inputs
TX [0:3][0:4]. The SSTL_2 TC
clock provided by the sender of
transmit data is used for all channels as the transmit byte clock.
The TX [0:3][0:4] and TC signals
must be properly aligned, as
shown in Figure 3.
TX PLL/CLOCK GENERATOR
The transmitter Phase Locked
Loop and Clock Generator (TX
PLL/CLOCK GENERATOR) block
generates all internal clocks
needed by the transmitter section
to perform its functions. These
clocks are based on the transmit
byte clock (TC). TC is also used
to determine the sampling window for the incoming data
latches. Incoming data is synchronous with TC (see Figure 3).
FRAME MUX
The FRAME MUX accepts the
10-bit-wide parallel data from the
INPUT LATCH. Using internally
generated high-speed clocks, this
parallel data is multiplexed into
the 1250 MBd serial data
streams. The data bits are transmitted sequentially, from TX [0]
to TX [4]. The leftmost bit of
K28.5 is on TX [0].
SERIAL OUTPUT SELECT
The OUTPUT SELECT block provides a parallel loopback mode
for testing purposes. In normal
operation, PLUP is set low and
the serialized TX [0:3] [0:4] data
are placed at SO [0:3] +/-.
When parallel wrap-mode is activated by setting PLUP high, the
SO [0:3]+/- pins are held static
at logic 1 and the serial output
signal reflecting TX [0:3] [0:4]
data is internally wrapped to the
INPUT SELECT block of the receiver section.
SERIAL INPUT SELECT
The INPUT SELECT block determines whether the signal at
SI [0:3]+/- or the internal loopback serial signal is used to drive
RX [0:3] [0:4]. In normal operation, PLUP is set low and the
serial data is accepted at
SI [0:3]+/-.
When PLUP is set high, the outgoing high-speed serial signal is
internally looped back from the
transmitter section to the receiver
section. This feature allows parallel loopback testing, exclusive
of the transmission medium.
RX PLL/CLOCK RECOVERY
The RX PLL/CLOCK RECOVERY
block is responsible for frequency
and phase locking onto the incoming serial data stream and
recovering the bit and byte
clocks. It does this by continually
frequency locking onto the
125 MHz reference clock, and
then phase locking onto the selected input data stream. An
internal signal detection circuit
monitors the presence of the
input, and invokes the phase
detection once the minimum
differential input signal level is
supplied (AC Electrical
Specifications).
Once bit locked, the receiver
generates the high-speed sampling clock at 1250 MHz for the
input sampler.
3
SERIAL INPUT SAMPLER
The INPUT SAMPLER converts
the serial input signal into a
retimed bit stream. In order to
accomplish this, it uses the highspeed serial clock recovered from
the RX PLL/CLOCK RECOVERY
block. This serial bit stream is
sent to the FRAME DEMUX AND
BYTE SYNC block.
FRAME DEMUX, BYTE SYNC
The FRAME DEMUX AND BYTE
SYNC block is responsible for
restoring the 10-bit character
from the high-speed serial bit
stream. This block is also responsible for recognizing the comma
character (K28.5+) of positive
disparity (0011111xxx). When
recognized, the FRAME DEMUX
AND BYTE SYNC block works
with the RX PLL/CLOCK RECOVERY block to properly select the
parallel data edge out of the bit
stream so that the comma character starts at RX[0:3][0]. When a
comma character is detected and
realignment of the receiver byte
clock RC[0:3][0:1] is necessary,
this clock is stretched, not slivered, to the next possible correct
alignment position. This clock will
be fully aligned by the start of the
second 2-byte or 4-byte ordered
set. The second comma character
received will be aligned with the
rising edge of RC[0:3][1].
Comma characters of positive
disparity must not be transmitted
in consecutive bytes to allow the
receiver byte clocks to maintain
their proper recovered
frequencies.
PARALLEL OUTPUT DRIVERS
The OUTPUT DRIVERS present
the recovered 10-bit character in
two groups onto the 5-pin RX
bus, properly aligned to the receive byte clock RC [0:3] [0:1] as
shown in Figure 5. These output
data buffers provide single-ended
SSTL_2 compatible signals. Unlike the TX, where all four channels are driven with the same
transmit byte clock (TC), each
receive channel provides its own
clock aligned with its own data,
so the recovered clocks may not
be phase aligned.
SSTL_2 COMPATIBILITY
HDMP-1685A works with protocol devices whose VDDQ voltage
is nominally set at 2.5 Volts.
RX [0:3][0:4], RC [0:3][0:1] pins
generate output voltages that are
compatible with the SSTL_2
standard (EIA/JESD8-9). In addition, these devices provide a
VREFR output pin allowing the
receiving device to differentially
detect a high or a low. The
devices receive inputs on their
TX [0:3][0:4] and TC pins that
are also SSTL_2 compatible. The
VREFT input pin is driven by a
voltage divider whose supply
voltage is at the same level as the
VDDQ supply of the protocol
device. This allows differential
detection of a high or a low at TX
parallel inputs.
RFCT
RX3
RC31/0
TX3
RX2
TX2
RC21/0
TC
RX1
RC11/0
TX1
RX0
RC01/0
TX0
4-CHANNEL ASIC
SI3
SO3
SI2
SO2
SI1
SO1
SI0
SO0
HDMP-1685A
TX(0:3)[0:4]
INPUT
LATCH
Figure 1. Typical application of the four channel SERDES.
FRAME
MUX
OUTPUT
SELECT
SO[0:3]±
PLUP
TX PLL
CLOCK
GENERATOR
TC
CAP0
CAP1
OUTPUT
DRIVER
FRAME
DEMUX
AND
BYTE SYNC
Figure 2. Block diagram of HDMP-1685A.
4
INPUT
SELECT
RX PLL
CLOCK
RECOVERY
RFCT
RC(0:3)[0:1]
SYNC
SYN(0:3)
RX(0:3)[0:4]
TX CLOCKS
RX CLOCKS
INPUT
SAMPLER
Sl[0:3]±
HDMP-1685A Timing Characteristics – Transmitter Sections
TA = 0°C to T C = 85°C, VCC = 3.15 V to 3.45 V
Symbol
Parameter
Units
tTXCT[2]
tTXCV[2]
TX [0:3][0:4] Input Data and TC Clock Transition Range
ps
TX [0:3][0:4] Input Data and TC Clock Valid Time
ps
t_txlat[1]
Transmitter Latency
ns
bits
Min.
Typ.
Max.
1600
2400
4
5
Note:
1. The transmitter latency, as shown in Figure 4, is defined as the time between the leading edge of the first half of a parallel 10-bit word and the
leading edge of the first transmitted serial output bit of that 10-bit word.
2. Agilent‘s HDMP-1685A internally generates another clock which is 90 degrees out of phase with the TC clock supplied. This clock, which will
have its edges at the center of the data valid eye, is used to clock in the TX[0:4] data. Setup and hold times are taken care of by the
HDMP-1685A provided the specifications indicated are met.
8 ns
TXCT
TX[0:3][0:4]
TXCV
TXCV
TC
Figure 3. Transmitter section parallel input timing.
10-BIT CHAR A
10-BIT CHAR B
SO[0:3]±
TX[0]
TXLAT
TX[0:3][0:4]
CHAR B[4:0]
CHAR B[9:5]
TC
Figure 4. Transmitter section latency. TX[0] is first on serial wire.
5
TX[9]
HDMP-1685A Timing Characteristics – Receiver Sections – Rising Edge Clocking
TA = 0°C to TC = 85°C, VCC = 3.15 V to 3.45 V
Symbol
Parameter
Units
f_lock
Frequency Lock at Powerup
µs
500
B_sync[1,2]
Bit Sync Time
bits
2500
tRXS
RX [0:3][0:4] Setup Time (Data Valid Before Clock)
ps
1200
tRXH
RX [0:3][0:4] Hold Time (Data Valid After Clock)
ps
800
RC [0:3][1] to RC [0:3][0] Skew
ns
3.5
4.5
RC [0:3][1] and RC [0:3][0] Duty Cycle
%
40
60
Receiver Latency
ns
bits
t_rxlat[3]
Min.
Typ.
Max.
16
20
Notes:
1. This is the recovery time for input phase jumps, per the Fibre Channel Specification X3.230-1994 FC-PH Standard, Sec 5.3.
2. Tested using CPLL = 0.1 µF.
3. The receiver latency, as shown in Figure 6, is defined as the time between receiving the first serial bit of a parallel data word (defined as the
edge of the first serial bit) and the clocking out of that parallel word (defined by the rising edge of the receive byte clock, RC [0:1]).
8 ns
RC[0:3][1]
RC[0:3][0]
RXS
RXS
RXH
RXH
RX[0:3][0:4]
Figure 5a. Receiver section parallel output timing using rising edge of both RC[0:3][0] and RC[0:3][1].
6
HDMP-1685A Timing Characteristics – Receiver Sections – Rising and Falling Edge Clocking
TA = 0°C to T C = 85°C, VCC = 3.15 V to 3.45 V
Symbol
Parameter
Units
f_lock
Frequency Lock at Powerup
µs
500
B_sync[1,2]
Bit Sync Time
bits
2500
tRXS
RX [0:3][0:4] Setup Time (Data Valid Before Clock)
ps
1000
tRXH
RX [0:3][0:4] Hold Time (Data Valid After Clock)
ps
800
RC [0:3][1] and RC [0:3][0] Duty Cycle
%
40
Receiver Latency
ns
bits
t_rxlat[3]
Min.
Typ.
Max.
60
16
20
Notes:
1. This is the recovery time for input phase jumps, per the Fibre Channel Specification X3.230-1994 FC-PH Standard, Sec 5.3.
2. Tested using CPLL = 0.1 µF.
3. The receiver latency, as shown in Figure 6, is defined as the time between receiving the first serial bit of a parallel data word (defined as the
edge of the first serial bit) and the clocking out of that parallel word (defined by the rising edge of the receive byte clock, RC [0:1]).
8 ns
RC[0:3][0]
or
RC[0:3][1]
RXS
RXS
RXH
RXH
RX[0:3][0:4]
Figure 5b. Receiver section parallel output timing using rising and falling edge of either RC[0:3][0] or RC[0:3][1].
10-BIT CHAR B
10-BIT CHAR C
SI[0:3]±
RX[0]
RX[9]
RXLAT
RX[0:3][0:4]
CHAR A[4:0]
RC[0:3][1]
RC[0:3][0]
Figure 6. Receiver section latency. First bit on serial wire drives RX[0:3][0].
7
CHAR A[9:5]
CHAR B[4:0]
HDMP-1685A Absolute Maximum Ratings
TA = 25°C, except as specified. Sustained operation at or beyond any of these conditions may result in long-term
reliability degradation or permanent damage, and is not recommended.
Symbol
Parameter
Units
Min.
Max.
VCC
Supply Voltage
V
–0.5
5.0
VIN,LVTTL
RFCT LVTTL Input Voltage
V
–0.7
VCC + 2.8
VIN,SSTL
SSTL Input Voltage
V
–0.7
VCC + 0.7
VIN,HS_IN
HS_IN Input Voltage (Differential)
V
Tstg
Storage Temperature
°C
–65
+150
Tj
Junction Temperature
°C
0
+125
TC
Case Temperature
°C
0
95
2.2
HDMP-1685A Guaranteed Operating Rates
TA = 0°C to TC = 85°C, VCC = 3.15 V to 3.45 V
Parallel Clock Rate (MHz)
Min.
Max.
Serial Baud Rate (MBaud)
Min.
Max.
124.0
1240
126.0
1260
HDMP-1685A Reference Clock and Transmit Byte Clock Requirements
TA = 0°C to TC = 85°C, VCC = 3.15 V to 3.45 V
Symbol
Parameter
Units
Min.
Typ.
Max.
f
Nominal Frequency
MHz
Ftol
Frequency Tolerance
ppm
–100
+100
SymmRFC
Symmetry (Duty Cycle) Reference Clock
%
40
60
SymmTC
Symmetry (Duty Cycle) Transmit Byte Clock
%
40
60
125
HDMP-1685A LVTTL I/O DC Electrical Specifications
TA = 0°C to TC = 85°C, VCC = 3.15 V to 3.45 V
Symbol
Parameter
Units
Min.
VIH,LVTTL
LVTTL Input High Voltage Level,
Guaranteed High Signal for All Inputs
V
2
5.5
VIL,LVTTL
LVTTL Input Low Voltage Level,
Guaranteed Low Signal for All Inputs
V
0
0.8
VOH,LVTTL
LVTTL Output High Voltage Level, IOH = –400 µA
V
2.2
VCC
VOL,LVTTL
LVTTL Output Low Voltage Level, IOL = 1 mA
V
0
0.5
IIH,LVTTL
Input High Current, VIN = 2.4 V, VCC = 3.45 V
µA
40
IIL,LVTTL
Input Low Current, VIN = 0.4 V, VCC = 3.45 V
µA
–600
8
Typ.
Max.
HDMP-1685A SSTL_2 I/O DC Electrical Parameters
TA = 0°C to T C = 85°C, VCC = 3.15 V to 3.45 V, VDDQ = 2.30 V to 2.70 V. VDDQ is the FC-1/MAC device I/O supply voltage.
SSTL-2 inputs can receive LVTTL signals successfully. SSTL-2 outputs do not output LVTTL compliant levels.
Symbol
Parameter
Units
Min.
Typ.
Max.
VREFT
SSTL_2 Input Reference Voltage
V
1.15
1.25
1.35
VIH
Input High Voltage
V
VREFT +0.18
VDDQ +0.30
VIL
Input Low Voltage
V
–0.30
VREFT –0.18
VREFR
SSTL_2 Output Reference Voltage
V
1.15
VOH
Output High Voltage
V
VREFR +0.38
VDDQ
VOL
Output Low Voltage
V
GND
VREFR –0.38
1.25
1.35
HDMP-1685A AC Electrical Specifications (TRx)
TA = 0°C to T C = 85°C, VCC = 3.15 V to 3.45 V
Symbol
Parameter
Units
Min.
Typ.
Max.
tr,RFCT
RFCT LVTTL Input Rise Time, 0.8 to 2.0 Volts
ns
0
2.4
tf,RFCT
RFCT LVTTL Input Fall Time, 2.0 to 0.8 Volts
ns
0
2.4
tr,SSTLo
SSTL Output Rise Time, 1.0 V to 1.6 V
ns
0.4
1.5
tf,SSTLo
SSTL Output Fall Time, 1.6 V to 1.0 V
ns
0.28
1.5
trs, HS_OUT
HS_OUT Single-Ended (SO[0:3]±) Rise Time (20% - 80%) ps
85
205
300
tfs, HS_OUT
HS_OUT Single-Ended (SO[0:3]±) Fall Time (20% - 80%)
ps
85
180
300
trd, HS_OUT
HS_OUT Differential Rise Time
ps
85
300
tfd, HS_OUT
HS_OUT Differential Fall Time
ps
85
300
VIP,HS_IN
HS_IN (SI[0:3]±) Input Peak-To-Peak Differential Voltage mV
200
1200
2000
VOP,HS_OUT [1]
HS_OUT Output Pk-Pk Diff. Voltage (Z0=50 Ohms, Fig.10) mV
1000
1300
1800
Note:
1. Output Peak-to-Peak Differential Voltage specified as SO[0:3]+ minus SO[0:3]–. The amplitude will be 25% higher when terminating into 75 Ω
loads.
X1
WAVEFORM MATH
f1 = 3 – 4
f2 = 1 – 2
X2
FUNCTION
f1
f2
DEFINE
FUNCTION...
DISPLAY
off
on
VERTICAL SCALE
auto
120.0 ps/div
130.3664 ns
Y
1 (f2) = –637.00 mV
2 (f2) = 636.00 mV
∆ =
9
Y SCALE
X
130.549 ns
131.349 ns
800 ps
1.27300 V
1/∆X = 1.250 GHz
Figure 7. Eye diagram of a high speed differential output.
manual
250 mV/div
Y OFFSET
0.0 V
HDMP-1685A Output Jitter Characteristics – Transmitter Section
TA = 0°C to TC = 85°C, VCC = 3.15 V to 3.45 V
Symbol
Parameter
Units
Typ.
RJ[1]
Random Jitter at DOUT, the High Speed Electrical Data Port,
specified as 1 sigma deviation of the 50% crossing point (RMS)
ps
11
DJ[1]
Deterministic Jitter at DOUT, the High Speed Electrical Data Port (pk-pk)
ps
26
Note:
1. Defined by Fibre Channel Specification X3.230-1994 FC-PH Standard, Annex A, Section A.4 and tested using measurement method shown
in Figure 8.
A 70841B
PATTERN
GENERATOR
A 70311A
CLOCK SOURCE
+K28.5, -K28.5
A 70841
PATTERN
GENERATOR
+ DATA
- DATA
1.25 GHz
A 83480A
OSCILLOSCOPE
A 83480A
OSCILLOSCOPE
1000001111
+ DATA
- DATA
125 MHz
TRIGGER
CH1
CH2
DIVIDE
BY 10
CIRCUIT
DIVIDE
BY 2
TRIGGER
CH1
CH2
A 70311A
CLOCK SOURCE
SOi+
BIAS
TEE
SOi–
HDMP-1685
SOi+
VARIABLE
DELAY
TXi[0:4]
125 MHz
SYNC
PLUP
TC
TXi[0:4]
1.4 V
SIi–
SIi+
HDMP-1685A
HDMP-1685
PLUP
TC
SOi–
RXi[0:4]
0011111000
(STATIC K28.7)
A. BLOCK DIAGRAM OF RJ MEASUREMENT METHOD
B. BLOCK DIAGRAM OF DJ MEASUREMENT METHOD
Figure 8. Transmitter jitter measurement method.
HDMP-1685A Thermal and Power Temperature Characteristics (TRx)
TA = 0°C to TC = 85°C, VCC = 3.15 V to 3.45 V
Symbol
Parameter
Units
Typ.
Max.
ICC,TRx
Transceiver VCC Supply Current, TA = 25°C
mA
900
PD, TRx [1]
Transceiver Power Dissipation, Outputs Connected
per Recommended Bias Terminations with 27–1 PRBS Pattern
W
2.97
Θjc[1]
Thermal Resistance, Junction to Case
°C/W
7.8
Tj
Junction Temperature (absolute maximum)
°C
0
+125
TC
Case Temperature (absolute maximum)
°C
0
+95
3.5
Note:
1. Based on independent package testing by Agilent. Θja for these devices is 36°C/W for the HDMP-1685A. Θja is measured on
a standard 3x3" FR4 PCB in a still air environment. To determine the actual junction temperature in a given application, use the following:
Tj = Tc + (Θjc x PD), where Tc is the case temperature measured on the top center of the package and PD is the power being dissipated.
10
HDMP-1685A I/O Type Definitions
I/O Type
Definition
I-LVTTL
Input LVTTL, floats high when left open
I-SSTL2
Input SSTL_2, floats low when left open
O-SSTL2
Output SSTL_2
HS_OUT
50 Ω matched Output Driver. Will drive AC coupled 50 Ω loads. PECL level compatible (Figure 10).
HS_IN
PECL level compatible. Must be AC coupled (Figure 10).
C
External Circuit Node
S
Power Supply or Ground
HDMP-1685A Pin Input Capacitance (TRx)
Symbol
Parameter
Units
Typ.
CINPUT
Input Capacitance on SSTL input pins
pF
1.6
I_TTL
VCC
VCC
VBB 1.4 V
GND
ESD
PROTECTION
GND
Figure 9. LVTTL input simplified circuit schematic (for RFCT).
HS_OUT
HS_IN
VCC
VCCP
Zo
+
–
VCC
Zo
+
–
VCC
SO[0:3]+
SI[0:3]+
Zo = 50 Ω
0.01 µF
2 * Zo
= 100 Ω
SO[0:3]–
Zo = 50 Ω
0.01 µF
GND
SI[0:3]–
GND
ESD
ESD
PROTECTION
PROTECTION
GND
GND
NOTES:
1. HS_IN INPUTS SHOULD NEVER BE CONNECTED TO GROUND AS PERMANENT DAMAGE TO THE DEVICE MAY RESULT.
2. CAPACITORS MAY BE PLACED AT THE SENDING END OR THE RECEIVING END.
Figure 10. HS_OUT and HS_IN simplified circuit schematic.
11
Max.
VCC (SERDES) = 3.3 V
VCC (SERDES) = 3.3 V
VCC (MAC)
VDDQ (MAC)
R1
VCC
VCC
0.1 µF
VDDQ
R2
VREFR
VREFT
RS = 50 Ω
UNTERMINATED
RX[0:3][0:4]
RC[0:3][0:1]
DATAIN
RS = 50 Ω
USE TERMINATION, IF NECESSARY, TO
DELIVER PROPER VOLTAGE SWINGS AT TX[0:4]
TX[0:3][0:4]
DATAOUT
TC
VDDQ (MAC)
R1
VREFT
0.1 µF
R2
HDMP-1685
MAC
NOTE: VREFR ON EACH DEVICE MAY BE USED TO DRIVE VREFT ON THE OTHER DEVICE INSTEAD OF USING
THE CONFIGURATION ABOVE. VREFR SHOULD BE BYPASSED WITH 0.1 µF IN THIS CASE. IF USED, R1 AND R2
SHOULD BE 500-1000 Ω. 1% RESISTORS SHOULD BE USED FOR R1 AND R2. WHEN USING THE CONFIGURATION
ABOVE, VREFT TO THE MAC SHOULD BE SET TO 1.25 V NOMINAL. USING THIS VALUE CENTERS VREFR RELATIVE
TO THE RX[0:3][0:4] OUTPUT SWINGS PROVIDED BY THE HDMP-1685A.
Figure 11. O-SSTL_2 and I-SSTL_2 simplified circuit schematic.
A
01
02
GND
VCC
03
04
05
06
07
08
GND SYN1 RC10 RX10 RX14
B
09
10
VCR1 VCC
11
12
13
14
GND RX21 VCR2
15
16
17
GND VCR2 GND
GND RC11 RX11 VCR1
GND SYN2 RX20 RX22
SYN3 RC30 RC31
C
RX04
VCR0 VCR1 RX12 GND
RC20 VCR2 RX23
VCC VCR3 GND RX30
D
RX00 RX01 VCR0 GND GND RX13 VRFR
RC21 GND RX24
RX31 RX32 RX33 RX34
E
RC00 RC01 RX02 RX03
F
SYN0 VCR0 GND
G
GND
VCR3 GND
GND
VCC
GND
TX22 TX21 TX20 VCR3
H
TX14
GNDA
J
TX10 TX11 TX12 TX13
VCCP
VCC
K
GND GND
VCC
GND GND
L
GND
VCCA
TX33 TX32 TX31 TX30
VCC
TX04
N
TX00 TX01 TX02 TX03
P
VRFT
R
RFCT
U
TC
TX34
PLUP VCC
GND SO0— GND SO1— GND CAP0 GND SO2+ GND SO3+
GND
GND
VCC SO0+ GND SO1+ GNDA CAP1 GND SO2— GND SO3— VCC
GND
VCC
VCC VCP0 GND VCP1 GND VCCA GND VCP2 GND VCP3 VCC
GND GND
GND GND SIO— SI0+
VCC
Figure 12. Pinout of HDMP-1685A (top view).
12
VCC
VCR
M
T
TX24 TX23
VCC SYNC
SI1— SI1+ GND GND SI2— SI2+ GND SI3— SI3+ GND GND GND
+
VCC
10 µF *
Filtering Schematic
C5
D3
0.1 µF
F3
G4
A16
A13
A10
VCR
VCR
VCR
0.1 µF
VCR
VCR
VCR
VCR
VCC
VCR
VCR
VCR
VCC
L4
VCR
VCC
B7
A2
VCC
C4
A9
0.1 µF
0.1 µF
HDMP-1685A
GUIDELINES FOR
DECOUPLING CAPACITOR
PLACEMENTS/CONNECTIONS
VCR
C11
C14
0.1 µF
C15
E14
G17
VCC
VCC
J14
VCC
N15
0.1 µF
K16
VCC
0.1 µF
0.1 µF
0.1 µF
R4
0.1 µF
VCC
02
03
04
10 µF
05
06
GND
VCC
C
07
08
09
VCR
VCR
VCR
GND
GND
F
VCR
GND
G
GND
VCC
E
VCC
VCC
T14
R14
VCP
10
11
12
13
14
16
17
GND
VCR
GND
VCC
VCR
GND
VCR
GND
10 µF*
VCC
15
0.1 µF
GND
VCR
GND
VCR
VCR
PLACEMENT NOT CRITICAL. INDICATES
THE NEED FOR ADDITIONAL LOW FREQUENCY
CAPACITIVE DECOUPLING.
+ OPTIONAL – PROVIDES INCREASED LOW
FREQUENCY DECOUPLING.
GND
GND
D
T13
T11
0.1 µF
0.1 µF
B
R16
0.1 µF
*
+
10 µF
+
0.1 µF
A
0.1 µF
1 µH
+
0.1 µF
01
VCP
VCCA
T9
VCP
T7
T5
U5
T3
T4
VCP
VCC
VCC
VCC
VCC
VCC
GND
VCR
GND
0.1 µF
0.1 µF
GND
VCR
0.1 µF
* 10 µF PLACEMENT NOT CRITICAL – INDICATES
NEED FOR LOW-FREQUENCY BYPASS CAPACITANCE
H
VCC
J
GND
GND
L
GND
VCC
0.1 µF
K
HDMP-1685A
GND
GND
VCC
M
0.1 µF
N
GND
GND
GND
GND
GND
VCC
GND
GND
GND
GND
GND
T
U
GND
GND
VCC
VCC
VCP
VCC
0.1 µF
GND
VCP
GND VCCA GND
GND GND
0.1 µF
10 µF
13
VCP
GND
GND
0.1 µF
VCP
VCC
GND
VCC
VCC
GND
GND
GND
GND
0.1 µF
TO VCCA PI-FILTER (SEE SCHEMATIC)
0.1 µF
R
VCC
GND
P
GND
HDMP-1685A TRx I/O Definition
Name
Pin
Type
Signal
CAP0
P09
C
Loop Filter Capacitor: A loop filter capacitor for the internal PLLs must be connected
across the CAP0 and CAP1 pins. (typical value = 0.1 µF)
CAP1
R09
PLUP
N14
I-SSTL2
Parallel Loopback Enable Input: When set high, a high-speed serial signal from the
transmitter section’s serial output select block, reflecting TX data, is driven to the
receiver section’s serial input select block. RX data reflects this serial signal. Also
when in parallel loopback mode, the SO [0:3]+/- outputs are held static at logic 1.
RFCT
R01
I-LVTTL
LVTTL Reference Clock: RFCT is a 125 MHz clock signal supplied to the IC.
RC00
RC01
RC10
RC11
RC20
RC21
RC30
RC31
E01
E02
A05
B05
C10
D10
B16
B17
O-SSTL2
Receiver Byte Clocks: The receiver sections drive 125 MHz receive byte
clocks RC [0:3] [0:1].
RX00
RX01
RX02
RX03
RX04
RX10
RX11
RX12
RX13
RX14
RX20
RX21
RX22
RX23
RX24
RX30
RX31
RX32
RX33
RX34
D01
D02
E03
E04
C01
A06
B06
C06
D06
A07
B11
A12
B12
C12
D12
C17
D14
D15
D16
D17
O-SSTL2
Data Outputs: Four 5-pin data busses. RX [0:3] [0] are the first bits received.
SI0+
SI0SI1+
SI1SI2+
SI2SI3+
SI3-
U04
U03
U07
U06
U11
U10
U14
U13
HS_IN
Serial Data Inputs: High-speed inputs. Serial data are accepted from the SI [0:3]+/inputs except when PLUP is high.
14
HDMP-1685A TRx I/O Definition, continued
Name
Pin
Type
Signal
SO0+
SO0SO1+
SO1SO2+
SO2SO3+
SO3-
R05
P05
R07
P07
P11
R11
P13
R13
HS_ OUT
Serial Data Outputs: High-speed outputs. These lines are active except when
PLUP is high, in which case these outputs are held static at logic 1.
SYNC
R17
I-SSTL2
Enable Byte Sync Input: When high, turns on the internal byte sync functions to allow
clock synchronization to a comma character of positive disparity (0011111XXX). When
the line is low, the function is disabled and will not reset registers and clocks, or strobe
the SYN [0:3] lines.
SYN0
SYN1
SYN2
SYN3
F02
A04
B10
B15
O-SSTL2
Byte Sync Outputs: Active high outputs. Used to indicate detection of a comma
character of positive disparity (0011111XXX) when SYNC is enabled.
TC
K17
I-SSTL2
Transmit Byte Clock: This signal is used to latch transmit data for all channels
into the IC.
TX00
TX01
TX02
TX03
TX04
TX10
TX11
TX12
TX13
TX14
TX20
TX21
TX22
TX23
TX24
TX30
TX31
TX32
TX33
TX34
N01
N02
N03
N04
M01
J01
J02
J03
J04
H01
G16
G15
G14
H17
H16
L17
L16
L15
L14
M17
I-SSTL2
Data Inputs: Four 5-pin data busses. TX [0:3] [0] are the first bits transmitted.
VREFT
P01
I-S
TX Parallel Interface SSTL_2 Reference Voltage: Voltage reference derived from
2 resistor network with VDDQ (ASIC) as supply, as recommended in Figure 11.
VREFR
D07
O-S
RX Parallel Interface SSTL_2 Reference Voltage: Provided by HDMP-1685A.
Drives the VREF input of the ASIC.
15
HDMP-1685A TRx I/O Definition, continued
Name
Pin
Type
Signal
VCC
A02
A10
C14
G04
J14
K16
L04
N15
R04
R14
R16
T03
T04
T14
U05
S
Power Supply: Normally 3.3 volts. Used for logic, SSTL inputs, and LVTTL I/O.
VCCA
T09
S
Analog Power Supply: Normally 3.3 volts. Used to provide a clean supply line for the
PLLs and high-speed analog cells.
VCR0
C04
D03
F03
A09
B07
C05
A13
A16
C11
C15
E14
G17
S
Rx SSTL2 Output Power Supply: Normally 3.3 volts. Used for all SSTL2 receiver
output buffer cells.
VCP0
VCP1
VCP2
VCP3
T05
T07
T11
T13
S
High-Speed Output Supply: Normally 3.3 volts. Used only for the last stage
of the high-speed transmitter output cells (HS_OUT) as shown in Figure 10.
Due to high current transitions, this VCC should be well bypassed to a ground plane.
GNDA
R08
S
Analog Ground: Normally 0 volts. All GND pads on the chip are connected to one
ground slug in the package, which then distributes these to GND balls.
VCR1
VCR2
VCR3
16
HDMP-1685A TRx I/O Definition, continued
Name
Pin
Type
Signal
GND
A01
A03
A11
A15
A17
B04
B09
C07
C16
D04
D05
D11
E15
F04
F17
G03
K03
K04
K14
K15
L03
P04
P06
P08
P10
P12
R03
R06
R10
R12
R15
T02
T06
T08
T10
T12
T15
T16
U01
U02
U08
U09
U12
U15
U16
U17
S
Logic Ground: Normally 0 volts. All GND pads on the chip are connected to one
ground slug in the package, which then distributes these to GND balls.
17
HDMP-1685A TRx I/O Definition, continued
Name
Pin
NC
A08
A14
B01
B02
B03
B08
B13
B14
C02
C03
C08
C09
C13
D08
D09
D13
E16
E17
F01
F14
F15
F16
G01
G02
H02
H03
H04
H14
H15
J15
J16
J17
K01
K02
L01
L02
M02
M03
M04
M14
M15
M16
N16
N17
P02
P03
P14
P15
P16
P17
R02
T01
T17
18
Type
Signal
These pins are connected to an isolated pad and have no functionality.
They may be left open, or LVTTL levels may be applied.
Package Drawing
D1
A2
S
A
O (4x)
e
e
S
E1
E
D
C
B
A
1 2 3 4 5
(CAVITY DOWN)
(BACKFILL)
Nx0b
DETAIL A
ddd
Z
∅ eee M Z X Y
[–Z–] SEATING PLANE
A1 CORNER
[–X–]
D
[–Y–]
A3
[–Z–]
SEATING PLANE
(BACKFILL)
DETAIL A
E
DIMENSIONS IN MILLIMETERS
SYMBOL
MIN.
NOM.
1.35
1.50
1.65
A1
0.60
0.65
0.70
A2
0.85
0.90
0.95
A3
0.15
D
23.00 ± 0.20
D1
TOLERANCE OF FORM AND POSITION
SYMBOL
19
MIN.
NOM.
MAX.
A
20.32 BSC
E
23.00 ± 0.20
E1
20.32 BSC
MD/ME
17
N
208
N1
4
MAX.
O
0.60
ddd
0.15
b
0.60
eee
0.30
e
0.75
1.27 ± 0.10
0.90
A1
www.semiconductor.agilent.com
Data subject to change.
Copyright © 2001 Agilent Technologies, Inc.
May 7, 2001
Obsoletes 5988-1304EN
5988-2143EN