AGERE FW802A-DB Datasheet

FW802A Low-Power PHY IEEE* 1394A-2000 Two-Cable Transceiver/Arbiter Device
Supports PHY pinging and remote PHY access

Distinguishing Features

Compliant with IEEE Standard 1394a-2000, IEEE Standard for a High Performance Serial Bus
Low-power consumption during powerdown or
microlow-power sleep mode.
Supports extended BIAS_HANDSHAKE time for
enhanced interoperability with camcorders.
While unpowered and connected to the bus, will not
drive TPBIAS on a connected port even if receiving incoming bias voltage on that port.
Does not require external filter capacitors for PLL.
Does not require a separate 5 V supply for 5 V link
controller interoperability.
Interoperable across 1394 cable with 1394 physical
layers (PHY) using 5 V supplies.
Interoperable with 1394 link-layer controllers using
5 V supplies.
1394a-2000 compliant common mode noise filter
on incoming TPBIAS.
Powerdown features to conserve energy in battery-
powered applications include: — Device powerdown pin. — Link interface disable using LPS. — Inactive ports power down. — Automatic microlow-power sleep mode during
suspend.
Interface to link-layer controller supports Annex J
electrical isolation as well as bus-keeper isolation.

Features

packets.
Fully supports suspend/resume.
Supports PHY-link interface initialization and reset.
Supports 1394a-2000 register set.
Supports LPS/link-on as a part of PHY-link inter-
face.
Supports provisions of IEEE 1394-1995 Standard
for a High Performance Serial Bus.
Fully interoperable with FireWire† implementation
of IEEE 1394-1995.
Reports cable power fail interrupt when voltage at
CPS pin falls below 7.5 V.
Separate cable bias and driver termination voltage
supply for each port.
Meets IntelMobile Power Guideline 2000.

Other Features

64-pin TQFP package.
Single 3.3 V supply operation.
Data interface to link-layer controller provided
through 2/4/8 parallel lines at 50 Mbits/s.
25 MHz crystal oscillator and PLL provide transmit/
receive data at 100 Mbits/s, 200 Mbits/s, and 400 Mbits/s, and link-layer controller clock at 50 MHz.
Node power-class information signaling for system
power management.
Multiple separate package signals provided for ana-
log and digital supplies and grounds.
Data Sheet, Rev. 3
June 2001
Provides two fully compliant cable ports at
100 Mbits/s, 200 Mbits/s, and 400 Mbits/s.
Fully supports OHCI requirements.
Supports arbitrated short bus reset to improve
utilization of the bus.
Supports ack-accelerated arbitration and fly-by con-
catenation.
Supports connection debounce.
Supports multispeed packet concatenation.
IEEE is a registered trademark of The Institute of Electrical and
*
Electronics Engineers, Inc.
FireWire
† ‡ Intel is a registered trademark of Intel Corporation.
is a registered trademark of Apple Computer, Inc.
FW802A Low-Power PHY IEEE 1394A-2000 Two-Cable Transceiver/Arbiter Device
Data Sheet, Rev. 3
June 2001
Table of Contents
Contents Page
Distinguishing Features ......................................................................................................................................... 1
Features ................................................................................................................................................................ 1
Other Features ...................................................................................................................................................... 1
Description ............................................................................................................................................................. 3
Signal Information .................................................................................................................................................. 6
Application Information ........................................................................................................................................ 10
Crystal Selection Considerations ......................................................................................................................... 11
1394 Application Support Contact Information .................................................................................................... 12
Absolute Maximum Ratings ................................................................................................................................. 12
Electrical Characteristics ..................................................................................................................................... 13
Timing Characteristics ......................................................................................................................................... 16
Timing Waveforms ............................................................................................................................................... 17
Internal Register Configuration ............................................................................................................................ 18
Outline Diagrams ................................................................................................................................................. 23
Ordering Information ............................................................................................................................................ 23
List of Figures

Figures Page

Figure 1. Block Diagram ........................................................................................................................................ 5
Figure 2. Pin Assignments ..................................................................................................................................... 6
Figure 3. Typical External Component Connections ........................................................................................... 10
Figure 4. Typical Port Termination Network ........................................................................................................ 11
Figure 5. Dn, CTLn, and LREQ Input Setup and Hold Times Waveforms .......................................................... 17
Figure 6. Dn, CTLn Output Delay Relative to SYSCLK Waveforms .................................................................... 17
List of Tables

Tabl es Page

Table 1. Signal Descriptions................................................................................................................................... 7
Table 2. Absolute Maximum Ratings.................................................................................................................... 12
Table 3. Analog Characteristics............................................................................................................................ 13
Table 4. Driver Characteristics ............................................................................................................................. 14
Table 5. Device Characteristics ............................................................................................................................ 15
Table 6. Switching Characteristics ....................................................................................................................... 16
Table 7. Clock Characteristics ............................................................................................................................. 16
Table 8. PHY Register Map for the Cable Environment ...................................................................................... 18
Table 9. PHY Register Fields for the Cable Environment .................................................................................... 18
Table 10. PHY Register Page 0: Port Status Page ............................................................................................. 20
Table 11. PHY Register Port Status Page Fields ................................................................................................ 21
Table 12. PHY Register Page 1: Vendor Identification Page ............................................................................. 22
Table 13. PHY Register Vendor Identification Page Fields ................................................................................. 22
22 Agere Systems Inc.
Data Sheet, Rev. 3 FW802A Low-Power PHY IEEE 1394A-2000 June 2001 Two-Cable Transceiver/Arbiter Device

Description

The Agere Systems Inc. FW802A device provides the analog physical layer functions needed to implement a two-port node in a cable-based IEEE 1394-1995 and IEEE 1394a-2000 network.
Each cable port incorporates two differential line trans­ceivers. The transceivers include circuitry to monitor the line conditions as needed for determining connec­tion status, for initialization and arbitration, and for packet reception and transmission. The PHY is designed to interface with a link-layer controller (LLC).
The PHY requires either an external 24.576 MHz crystal or crystal oscillator. The internal oscillator drives an internal phase-locked loop (PLL), which generates the required 400 MHz reference signal. The 400 MHz reference signal is internally divided to provide the 49.152 MHz, 98.304 MHz, and
196.608 MHz clock signals that control transmission of the outbound encoded strobe and data information. The 49.152 MHz clock signal is also supplied to the associated LLC for synchronization of the two chips and is used for resynchronization of the received data. The powerdown function, when enabled by the PD signal high, stops operation of the PLL and disables all circuitry except the cable-not-active signal circuitry.
The PHY supports an isolation barrier between itself and its LLC. When /ISO is tied high, the link interface outputs behave normally. When /ISO is tied low, internal differentiating logic is enabled, and the outputs become short pulses, which can be coupled through a capacitor or transformer as described in the IEEE 1394-1995 Annex J. To operate with bus-keeper isolation, the /ISO pin of the FW802A must be tied high.
Data bits to be transmitted through the cable ports are received from the LLC on two, four, or eight data lines (D[0:7]), and are latched internally in the PHY in synchronization with the 49.152 MHz system clock. These bits are combined serially, encoded, and transmitted at 98.304 Mbits/s, 196.608 Mbits/s, or
393.216 Mbits/s as the outbound data-strobe information stream. During transmission, the encoded data information is transmitted differentially on the TPA and TPB cable pair(s).
During packet reception, the TPA and TPB transmitters of the receiving cable port are disabled, and the receivers for that port are enabled. The encoded data information is received on the TPA and TPB cable pair. The received data-strobe information is decoded to recover the receive clock signal and the serial data bits. The serial data bits are split into two, four, or eight parallel streams, resynchronized to the
local system clock, and sent to the associated LLC. The received data is also transmitted (repeated) out of the other active (connected) cable ports.
Both the TPA and TPB cable interfaces incorporate differential comparators to monitor the line states during initialization and arbitration. The outputs of these comparators are used by the internal logic to determine the arbitration status. The TPA channel monitors the incoming cable common-mode voltage. The value of this common-mode voltage is used during arbitration to set the speed of the next packet transmission. In addition, the TPB channel monitors the incoming cable common-mode voltage for the presence of the remotely supplied twisted-pair bias voltage. This monitor is called bias-detect.
The TPBIAS circuit monitors the value of incoming TPA pair common-mode voltage when local TPBIAS is inactive. Because this circuit has an internal current source and the connected node has a current sink, the monitored value indicates the cable connection status. This monitor is called connect-detect.
Both the TPB bias-detect monitor and TPBIAS connect-detect monitor are used in suspend/resume signaling and cable connection detection.
The PHY provides a 1.86 V nominal bias voltage for driver load termination. This bias voltage, when seen through a cable by a remote receiver, indicates the presence of an active connection. The value of this bias voltage has been chosen to allow interoperability between transceiver chips operating from 5 V or 3 V nominal supplies. This bias voltage source should be stabilized by using an external filter capacitor of approximately 0.33 µF.
The transmitter circuitry, the receiver circuitry, and the twisted-pair bias voltage circuity are all disabled with a powerdown condition. The powerdown condition occurs when the PD input is high. The port transmitter circuitry, the receiver circuitry, and the TPBIAS output are also disabled when the port is disabled, suspended, or disconnected.
The line drivers in the PHY operate in a high­impedance current mode and are designed to work with external 112 line-termination resistor networks. One network is provided at each end of each twisted­pair cable. Each network is composed of a pair of series-connected 56 resistors. The midpoint of the pair of resistors that is directly connected to the twisted-pair A (TPA) signals is connected to the PBIAS voltage signal. The midpoint of the pair of
Agere Systems Inc. 3
FW802A Low-Power PHY IEEE 1394A-2000 Data Sheet, Rev. 3 Two-Cable Transceiver/Arbiter Device June 2001
Description
resistors that is directly connected to the twisted-pair B (TPB) signals is coupled to ground through a parallel RC network with recommended resistor and capacitor values of 5 k and 220 pF, respectively.
The value of the external resistors are specified to meet the standard specifications when connected in parallel with the internal receiver circuits.
The driver output current, along with other internal operating currents, is set by an external resistor. This resistor is connected between the R0 and R1 signals and has a value of 2.49 kΩ ± 1%.
The FW802A supports suspend/resume as defined in the IEEE 1394a-2000 specification. The suspend mechanism allows an FW802A port to be put into a suspended state. In this state, a port is unable to transmit or receive data packets, however, it remains capable of detecting connection status changes and detecting incoming TPBias. When all ports of the FW802A are suspended, all circuits except the bias voltage reference generator, and bias detection circuits are powered down, resulting in significant power savings. The use of suspend/resume is recommended.
Four signals are used as inputs to set four configuration status bits in the self-identification (self­ID) packet. These signals are hardwired high or low as a function of the equipment design. PC[0:2] are the three signals that indicate either the need for power from the cable or the ability to supply power to the cable. The fourth signal, C/LKON, as an input, indicates whether a node is a contender for bus manager. When the C/LKON signal is asserted, it means the node is a contender for bus manager. When the signal is not asserted, it means that the node is not a contender. The C bit corresponds to bit 20 in the self-ID packet, PC0 corresponds to bit 21, PC1 corresponds to bit 22, and PC2 corresponds to bit 23 (see Table 4-29 of the IEEE 1394-1995 standard for additional details).
A powerdown signal (PD) is provided to allow a powerdown mode where most of the PHY circuits are powered down to conserve energy in battery-powered applications. The internal logic in FW802A is reset as long as the powerdown signal is asserted. A cable status signal, CNA, provides a high output when none of the twisted-pair cable ports are receiving incoming bias voltage. This output is not debounced. The CNA output can be used to determine when to power the PHY down or up. In the powerdown mode, all circuitry is disabled except the CNA circuitry. It should be noted
(continued)
that when the device is powered down, it does not act in a repeater mode.
When the power supply of the PHY is removed while the twisted-pair cables are connected, the PHY transmitter and receiver circuitry has been designed to present a high impedance to the cable in order to not load the TPBIAS signal voltage on the other end of the cable.
For reliable operation, the TPBn signals must be terminated using the normal termination network regardless of whether a cable is connected to a port or not connected to a port. For those applications, when FW802A is used with one of the ports not brought out to a connector, those unused ports may be left unconnected without normal termination. When a port does not have a cable connected, internal connect­detect circuitry will keep the port in a disconnected state.
Note: All gap counts on all nodes of a 1394 bus must
be identical. This may be accomplished by using PHY configuration packets (see Section 4.3.4.3 of IEEE 1394-1995 standard) or by using two bus resets, which resets the gap counts to the maximum level (3Fh).
The link power status (LPS) signal works with the C/LKON signal to manage the LLC power usage of the node. The LPS signal indicates that the LLC of the node is powered up or powered down. If LPS is inac­tive for more than 1.2 µs and less than 25 µs, PHY/link interface is reset. If LPS is inactive for greater than 25 µs, the PHY will disable the PHY/link interface to save power. FW802A continues its repeater function. If the PHY then receives a link-on packet, the C/LKON signal is activated to output a 6.114 MHz signal, which can be used by the LLC to power itself up. Once the LLC is powered up, the LPS signal communicates this to the PHY and the PHY/link interface is enabled. C/LKON signal is turned off when LPS is active or when a bus reset occurs, provided the interrupt that caused C/LKON is not present.
When the PHY/link interface is in the disabled state, the FW802A will automatically enter a low-power mode, if all ports are inactive (disconnected, disabled, or suspended). In this low-power mode, the FW802A disables its PLL and also disables parts of reference circuitry depending on the state of the ports (some ref­erence circuitry must remain active in order to detect incoming TP bias). The lowest power consumption (the microlow-power sleep mode) is attained when all ports are either disconnected or disabled with the ports inter­rupt enable bit cleared. The FW802A will exit the low­power mode when the LPS input is asserted high or when a port event occurs that requires the FW802A
4 Agere Systems Inc.
Data Sheet, Rev. 3 FW802A Low-Power PHY IEEE 1394A-2000 June 2001 Two-Cable Transceiver/Arbiter Device
Description
(continued)
to become active in order to respond to the event or to notify the LLC of the event (e.g., incoming bias or dis­connection is detected on a suspended port, a new connection is detected on a nondisabled port, etc.). The SYSCLK output will become active (and the PHY/ link interface will be initialized and become operative) within 3 ms after LPS is asserted high, when the FW802A is in the low-power mode.
CPS
LPS
/ISO
CNA
SYSCLK
LREQ
CTL0
CTL1
D0 D1 D2 D3 D4 D5 D6 D7
PC0 PC1 PC2
C/LKON
SE
SM
LINK
INTERFACE
I/O
RECEIVED
DATA
DECODER/
RETIMER
ARBITRATION
CONTROL
STATE
MACHINE
LOGIC
Two of the signals are used to set up various test conditions used in manufacturing. These signals (SE and SM) should be connected to V
for normal
SS
operation.
BIAS
VOLTAGE
AND
CURRENT
GENERATOR
AND
CABLE PORT 0
R0
R1
TPA0+ TPA0–
TPBIAS0
TPB0+ TPB0–
PD
TPA1+ TPA1– TPBIAS1 TPB1+ TPB1–
XI
XO
5-5459.f (F)
/RESET
TRANSMIT
DATA
ENCODER
CABLE PORT 1
CRYSTAL OSCILLATOR, PLL SYSTEM,
AND
CLOCK
GENERATOR

Figure 1. Block Diagram

Agere Systems Inc. 5
FW802A Low-Power PHY IEEE 1394A-2000 Two-Cable Transceiver/Arbiter Device

Signal Information

LREQ
V
CTL0
CTL1
D0
D1
V
DD
D2
D3
D4
D5
D6
D7
V
CNA
LPS
SS
V
64
1
SS
2
3
4
5
6
7
8
9
10
11
12
13
14
SS
15
16
17
/RESET
VDDSYSCLK
61
62
63
PIN #1 IDENTIFIER
18
19
20
PLLVSS
XI
XO
58
59
60
AGERE FW802A
21
22
23
Data Sheet, Rev. 3
June 2001
DDA
DDA
SSAVSSA
V
R0
R1
VSSPLLVDD
52
53
54
55
56
57
24
25
26
27
28
29
VSSA
V
V
49
50
51
30
48
NC
47
NC
46
NC
45
NC
44
NC
43
V
DDA
42
TPBIAS1
41
TPA1+
40
TPA1–
39
TPB1+
38
TPB1–
37
TPBIAS0
36
TPA0+
35
TPA0–
34
TPB0+
33
TPB0–
31
32
VDD
C/LKON
PD
PC0
PC1
PC2
SS
V
/ISO
CPS
VDD
VDD
SE
SM
DDAVDDA
V
Note: Active-low signals are indicated by “/” at the beginning of signal names, within this document.

Figure 2. Pin Assignments

SSA
V
5-6236.b (F)
66 Agere Systems Inc.
Data Sheet, Rev. 3 June 2001
FW802A Low-Power PHY IEEE
Two-Cable Transceiver/Arbiter Device
Signal Information
Table 1. Signal Descriptions
Pin Signal* Type Name/Description
18 C/LKON I/O Bus Manager Capable Input and Link-On Output. On hardware reset,
15 CNA O Cable-Not-Active Output. CNA is asserted high when none of the PHY
24 CPS I Cable Power Status. CPS is normally connected to the cable power
3 CTL0 I/O Control I/O. The CTLn signals are bidirectional communications control
4CTL1
5, 6, 8,
9, 10, 11,
12, 13
23 /ISO I Link Interface Isolation Disable Input (Active-Low). /ISO controls the
* Active-low signals are indicated by “/ ” at the beginning of signal names, within this document.
D[0:7] I/O Data I/O. The Dn signals are bidirectional and pass data between the
(continued)
this pin is used to set the default value of the contender status indicated during self-ID. The bit value programming is done by tying the signal through a 10 k resistor to V (low, not bus manager capable). Using either the pull-up or pull-down resistor allows the link-on output to override the input value when neces­sary.
After hardware reset, this pin is set as an output. If the LPS is inactive, C/LKON indicates one of the following events by asserting a 6.114 MHz signal.
1. FW802A receives a link-on packet addressed to this node.
2. Port_event register bit is 1.
3. Any of the Timeout, Pwr_Fail, or Loop register bits are 1 and the Resume_int register bit is also 1. Once activated, the C/LKON output will continue active until the LPS becomes active. The PHY also deas­serts the C/LKON output when a bus reset occurs, if the C/LKON is active due solely to the reception of a link-on packet.
Note: If an interrupt condition exists which would otherwise cause the
C/LKON output to be activated if the LPS were inactive, the C/LKON output will be activated when the LPS subsequently becomes inactive.
ports are receiving an incoming bias voltage. This circuit remains active during the powerdown mode.
through a 400 k resistor. This circuit drives an internal comparator that detects the presence of cable power. This information is maintained in one internal register and is available to the LLC by way of a register read (see Table 8, Register 0).
signals between the PHY and the LLC. These signals control the passage of information between the two devices. Bus-keeper circuitry is built into these terminals.
PHY and the LLC. Bus-keeper circuitry is built into these terminals.
operation of an internal pulse differentiating function used on the PHY-LLC interface signals, CTLn and Dn, when they operate as outputs. When /ISO is asserted low, the isolation barrier is implemented between PHY and its LLC (as described in Annex J of IEEE 1394-1995). /ISO is normally tied high to disable isolation differentiation. Bus-keepers are enabled when /ISO is high (inactive) on CTL, D, and LREQ. When /ISO is low (active), the bus-keepers are disabled. Please refer to Agere’s application note AP98-074CMPR for more information on isolation.
(high, bus manager capable) or to GND
DD
Agere Systems Inc. 7
FW802A Low-Power PHY IEEE 1394A-2000 Two-Cable Transceiver/Arbiter Device
Data Sheet, Rev. 3
June 2001
Signal Information
(continued)
Table 1. Signal Descriptions (continued)
Pin Signal* Type Name/Description
supplying the
16 LPS I Link Power Status. LPS is connected to either the V
DD
LLC or to a pulsed output that is active when the LLC is powered for the purpose of monitoring the LLC power status. If LPS is inactive for more than 1.2 µs and less than 25 µs, interface is reset. If LPS is inactive for greater than 25 µs, the PHY will disable the PHY/Link interface to save power. FW802A continues its repeater function.
1LREQ ILink Request. LREQ is an output from the LLC that requests the PHY to
perform some service. Bus-keeper circuitry is built into this terminal.
44, 45, 46,
NC No Connect.
47, 48
20 PC0 I Power-Class Indicators. On hardware reset, these inputs set the default
21 PC1
22 PC2
value of the power class indicated during self-ID. These bits can be programmed by tying the signals to V
(high) or to ground (low).
DD
19 PD I Powerdown. When asserted high, PD turns off all internal circuitry except
the bias-detect circuits that drive the CNA signal. Internal FW802A logic is kept in the reset state as long as PD is asserted. PD terminal is provided for backward compatibility. It is recommended that the FW802A be allowed to manage its own power consumption using suspend/resume in conjunction with LPS. C/LKON features are defined in 1394a-2000.
57 PLLV
DD
Power for PLL Circuit. PLLV
supplies power to the PLL circuitry
DD
portion of the device.
58 PLLV
SS
Ground for PLL Circuit. PLLVSS is tied to a low-impedance ground
plane.
54 R0 I Current Setting Resistor. An internal reference voltage is applied to a
resistor connected between R0 and R1 to set the operating current and the cable driver output current. A low temperature-coefficient resistor
55 R1
(TCR) with a value of 2.49 kΩ ± 1% should be used to meet the IEEE 1394-1995 standard requirements for output voltage limits.
61 /RESET I Reset (Active-Low). When /RESET is asserted low (active), the FW802A
is reset. An internal pull-up resistor, which is connected to V
DD
, is provided, so only an external delay capacitor is required. This input is a standard logic buffer and can also be driven by an open-drain logic output buffer.
28 SE I Test Mode Control. SE is used during the manufacturing test and should
be tied to V
SS
.
29 SM I Test Mode Control. SM is used during the manufacturing test and should
be tied to V
SS
.
63 SYSCLK O System Clock. SYSCLK provides a 49.152 MHz clock signal, which is
synchronized with the data transfers to the LLC.
36 TPA0+ Analog I/O Portn, Port Cable Pair A. TPAn is the port A connection to the twisted-
41 TPA1+
pair cable. Board traces from each pair of positive and negative differen­tial signal pins should be kept matched and as short as possible to the external load resistors and to the cable connector.
* Active-low signals are indicated by “/ ” at the beginning of signal names, within this document.
88 Agere Systems Inc.
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