CY7C65640-LFC Cypress Semiconductor Corp, CY7C65640-LFC Datasheet - Page 8

• Manufacturer Part Number: CY7C65640-LFC
• Manufacturer: Cypress Semiconductor Corp

Specifications of CY7C65640-LFC

• Operating Temperature (min): 0C
• Operating Temperature Classification: Commercial
• Operating Temperature (max): 70C
• Rad Hardened: No
• Lead Free Status / Rohs Status: Not Compliant

For high-speed multi-TT support, the host must also set the alternate interface setting to 1 (the default mode is single-TT). Once
the hub is configured, the full hub functionality is available.
4.3
After TetraHub is configured in a high-speed system, it will be in Single TT mode. The host may then set the hub into Multiple TT
mode by sending a SetInterface command. In Multiple TT mode, each full-speed port is handled independently and thus has a
full 12-Mbps bandwidth available. In Single TT mode, all traffic from the host destined for full- or low-speed ports will be forwarded
to all of those ports. This means that the 12-Mbps bandwidth is shared by all full- and low-speed ports.
4.4
TetraHub supports a maximum of four downstream ports, each of which may be marked as usable or removable in the extended
configuration (0xD2 EEPROM load, see section 8.2). Downstream D+ and D– pull-down resistors are incorporated in TetraHub
for each port. Prior to the hub being configured, the ports are driven SE0 (Single Ended Zero, where both D+ and D– are driven
low) and are set to the unpowered state. Once the hub is configured, the ports are not driven, and the host may power the ports
by sending a SetPortPower command to each port. After a port is powered, any connect or disconnect event is detected by the
hub. Any change in the port state is reported by the hub back to the host through the Status Change Endpoint (endpoint 1). Upon
receipt of SetPortReset command from the host, the hub will
Babble consists of either unterminated traffic from a downstream port (or loss of activity), or a non-idle condition on the port after
EOF2. If babble is detected on an enabled port, that port will be disabled. A ClearPortEnable command from the host will also
disable the specified port.
Downstream ports can be individually suspended by the host with the SetPortSuspend command. If the hub is not suspended,
any resume will be confined to that individual port and reflected to the host through a port change indication in the Hub Status
Change Endpoint. If the hub is suspended, a resume on this port will be forwarded to the host, but other resume events will not
be seen on that port. The host may resume the port by sending a ClearPortSuspend command.
4.5
The upstream port includes the transmitter and the receiver state machine. The Transmitter and Receiver operate in high-speed
and full-speed depending on the current hub configuration.
The transmitter state machine monitors the upstream facing port while the Hub Repeater has connectivity in the upstream
direction. This monitoring activity prevents propagation of erroneous indications in the upstream direction. In particular, this
machine prevents babble and disconnect events on the downstream facing ports of this hub from propagating and causing the
hub to be disabled or disconnected by the hub to which it is attached. This allows the Hub to only disconnect the offensive port
on detecting a babble from it.
4.6
TetraHub includes interface signals for external port power switches. Both ganged and individual (per-port) configurations are
supported, with individual switching being the default. Initially all ports are unpowered. After enumerating, the host may power
each port by sending a SetPortPower command for that port. The power switching and over-current detection of downstream
ports is managed by control pins connected to an external power switch device. PWR [n]# output pins of the CY7C65640 series
are connected to the respective external power switch's port power enable signals. (Note that each port power output pin of the
external power switch must be bypassed with an electrolytic or tantalum capacitor as required by the USB specification. These
capacitors supply the inrush currents, which occur during downstream device hot-attach events.)
4.7
Over-current detection includes timed detection of 8 ms by default. This parameter is configured from the external EEPROM in
a range of 0 ms to 15 ms for both an enabled port and a disabled port individually. Detection of over-current on downstream ports
is managed by control pins connected to an external power switch device.
The OVR[n]# pins of the CY7C65640 series are connected to the respective external power switch's port over-current indication
(output) signals. Upon detecting an over-current condition, the hub device reports the over-current condition to the host and
disables the PWR# output to the external power device.
Document #: 38-08019 Rev. *E
• Drive SE0 on the corresponding port
• Put the port in an enabled state
• Enable the green port indicator for that port (if not previously overridden by the host)
• Enable babble detection once the port is enabled.
Multiple Transaction Translator Support
Downstream Ports
Upstream Port
Power Switching
Over-current Detection
CY7C65640
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