DS33R11 Ethernet Mapper with Integrated T1/E1/J1 Transceiver

10 INTEGRATED T1/E1/J1 TRANSCEIVER

10.1 T1/E1/J1 Clocks

Figure 10-1 shows the clock map of the T1/E1 transceiver. The routing for the transmit and receive clocks are shown for the various loopback modes and jitter attenuator positions. Although there is only one jitter attenuator, which can be placed in the receive or transmit path, two are shown for simplification and clarity.

Figure 10-1. T1/E1/J1 Clock Map

 

 

 

 

 

 

MCLK

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TSYSCLK

MCLKS = 0

MCLKS = 1

 

 

 

 

 

 

 

PRE-SCALER

TR.LIC4.MPS0

 

 

 

 

 

 

 

 

 

TR.LIC4.MPS1

 

 

 

 

 

 

 

2.048 TO 1.544

TR.LIC2.3

 

 

 

 

 

 

 

SYNTHESIZER

 

 

 

 

 

 

 

 

 

 

 

 

 

DJA = 1

 

 

 

 

 

 

 

 

 

 

8 x PLL

 

 

8XCLK

 

LOCAL

JITTER ATTENUATOR

 

DJA = 0

 

 

 

 

 

 

 

 

 

 

 

 

LOOPBACK

SEE TR.LIC1

REMOTE

FRAMER

PAYLOAD

 

 

 

 

 

REGISTER

 

 

 

 

 

 

 

LOOPBACK

LOOPBACK

LOOPBACK

 

 

 

RCL = 1

 

 

JAS = 0

 

 

 

LLB = 0

 

 

 

(SEE NOTES)

BPCLK

 

 

 

AND

 

 

BPCLK

 

 

 

 

 

RXCLK

 

LTCA

DJA = 0

 

FLB = 0

 

SYNTH

 

 

 

RECEIVE

 

 

 

RCL = 0

LLB = 1

 

 

 

 

 

 

RCLK

 

 

JAS = 1

 

 

FRAMER

 

 

TO

 

 

 

FLB = 1

 

 

 

 

 

JAS = 0

OR

 

 

 

 

 

LIU

 

DJA = 1

 

 

 

 

 

 

 

 

OR

 

 

 

 

 

 

 

 

 

DJA = 1

 

RLB = 1

 

 

 

 

 

TXCLK

 

 

 

 

PLB = 1

 

 

 

 

 

 

 

 

 

 

 

 

 

LTCA

 

 

TRANSMIT

 

 

 

 

 

 

 

 

 

 

 

 

 

JAS = 1

 

RLB = 0

 

FORMATTER

 

 

 

 

 

AND

 

 

PLB = 0

 

 

 

 

 

DJA = 0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TCLKT

 

 

 

 

 

 

 

 

 

MUX

 

 

 

 

 

 

 

A

B

C

TCLKT

 

 

 

 

 

 

 

 

 

The TCLKT MUX is dependent on the state of the TCSS0 and TCSS1 bits in the TR.CCR1 register and the state of the TCLKT pin.

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Maxim DS33R11 specifications 10.1 T1/E1/J1 Clocks, T1/E1/J1 Clock Map