ST70235A STMicroelectronics, ST70235A Datasheet - Page 16

• Manufacturer Part Number: ST70235A
• Description: Transceiver 144-Pin TQFP
• Manufacturer: STMicroelectronics

Specifications of ST70235A

• Package: 144TQFP
• Power Supply Type: Analog
• Typical Operating Supply Voltage: 1.8|3.3 V
• Minimum Operating Supply Voltage: 1.62|3 V
• Maximum Operating Supply Voltage: 1.98|3.6 V
• Case: QFP

ST70235A
Figure 14 : Timing (Utopia 2 Receive Interface)
Pin Description
Note
When RxEnb is asserted, the ST70235A reads data from its internal fifo and presents it on RxData and
RxSOC on each low-to-high transition of RxClk, ie the ATM layer chip samples all RxData and RxSOC on
the rising edge of RxSOC on the rising edge of RxClk.
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RxClav
RxEnb
RxClk
RxData
RxSOC
RxRef
Name
Polling:
RxClk
RxAddr
RxClav
RxEnb*
RxData
RxSOC
Cell transmission from:
1. Active low signal
1
1
P41 P42
1F N-3
Type
1
O
O
O
O
I
I
2
Receive Cell available
Receive Enable
Receive Byte Clock
Receive Data (8bits)
Receive Start Cell
Reference Clock
N-3
P43 P44
1F
3
N+1
Meaning
4
PHY N
N+1
P45 P46 P47 P48
1F
5
N-1
6
Polling
N-1
1F
7
Signals to the ATM chip that the ST70235A
has a cell ready for transfer
Signals to the ST70235A that the ATM chip
will sample and accept data during next
clock cycle
Gives the timing signal for the transfer,
generated by ATM layer chip.
ATM cell data, from ST70235A chip to ATM
chip, byte wide. Rx Data [7] is the MSB.
Identifies the cell boundary on RxData
8 kHz clock transported over the network
N
8
1F
N
9
XX
N+3
10
N+3
Usage
1F
11
N-1
12
N-1
1F
13
Detection
N-3
14
N-3
1F
15
Selection
N-3
Remains active for the entire
cell transfer
RxData and RxSOC could be
tri-state when RxEnb* is
inactive (high). Active low
signal
Indicate to the ATM layer
chip that RxData contains
the first valid byte of a cell
Active low signal
16
N-3
1F
17
N+1
H1
Remark
18
Polling
PHY N-3
N+1
H2
1F
19
N+2
H3
20