BT8376EPF datasheet(202/323 Pages) CONEXANT

202 / 323 page

Bt8370/8375/8376

3.14 Clock Rate Adapter Registers

Fully Integrated T1/E1 Framer and Line Interface

3-84

Conexant

N8370DSE

LFGAIN[3:0]

Loop Filter Gain—Determines CLAD jitter tolerance and jitter attenuation characteristics by

selecting the NCO loop filter's proportional phase error gain. Lower gain values improve jitter

tolerance by reducing phase response time, but provide less jitter attenuation. Higher gain

values increase the phase response time and improve jitter attenuation at the expense of loop

acquisition time.

NOTE:

Loop instability or acquisition failures may result from incorrectly programmed

LFGAIN values. Typically, LFGAIN is programmed to provide a minimum 3 Hz loop

bandwidth and 20 dB/decade jitter attenuation with 6 Hz filter cutoff frequency.

LFGAIN values of 5 or 6 are typically chosen to meet jitter requirements.

091—CLAD Frequency Select (CSEL)

VSEL[3:0]

CLADV Frequency Select—Applicable only if CEN [addr 90] is active. Picks one of eight

CLAD divider chain frequencies to feed back to the CPHASE detector. (Refer to Tables 2-8

through 2-9 for programming examples.) The selected CLADV frequency passes to VSCALE

for further division before phase detector comparison.

LFGAIN

Proportional Gain

0000

1/20

1111

1/215

VSEL[3]

VSEL[2]

VSEL[1]

VSEL[0]

OSEL[3]

OSEL[2]

OSEL[1]

OSEL[0]

VSEL

CLADV Frequency (kHz)

0000

1024

0001

2048

0010

4096

0011

8192

0100

2560

0101

1544

0110

1536

0111

T1/E1 line rate x 2XSEL (addr 090)

1xxx

16,384

BT8376EPF Datasheet(PDF) 202 Page - Synaptics Incorporated.

BT8376EPF Datasheet(HTML) 202 Page - Synaptics Incorporated.

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL