FIGURE 3. Code Type Allowance Versus VCO Frequency Range

RANGE SELECT Input

Equivalent

Minimum N (Allowed Code Type)

( Note 1 )

VCO Range

NRZ Data Rate

2

1

0

MHz

MFM or 2,7

1

2

3

4

(Mbit/sec)

(GCR)

(MFM; 1, N)

(2,7)

(2,7)

1

1

X

0.50

≤ Fvco ≤ 1.25

0.250

≤ Fnrz ≤ 0.625

√√√

√

1

0

1

≤ 2.5

≤ 1.25

√√√

√

1

0

0

≤ 5

≤ 2.5

√√√

√

01

1

≤ 10

≤ 5

√√√

√

01

0

≤ 20

≤ 10

N/A

√√

√

00

X

≤ 50

≤ 25

N/A

√√

√

(Note3)

Note 1: N/A—Not Allowed.

Note 2: Operation slightly beyond listed range boundaries may be acceptable in some applications. At or near range boundaries, range selection should be made

to place the operating frequency near the UPPER boundary; e.g., use RS2 = 0, RS1 = 1, and RS0 = 0 for 10 Mb/s.

≤ 38 MHz for 1, N codes.

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PrintDate=1996/07/31 PrintTime=11:05:45 ds009322 Rev. No. 1

Proof

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