AD9520-2SLASHPCBZ datasheet(73/84 Pages) AD

73 / 84 page

AD9520-2

Rev. 0 | Page 73 of 84

Reg.

Addr

(Hex) Bit(s) Name

Description

[4]

[3]

[2]

[1]

[0]

Level or

Dynamic

Signal

Signal at REFMON Pin

LVL

Holdover active (active high).

LVL

LD pin comparator output (active high).

LVL

VS (PLL supply).

DYN

REF1 clock (differential reference when in differential mode).

DYN

REF2 clock (not available in differential mode).

DYN

Selected reference to PLL (differential reference when in

differential mode).

DYN

Unselected reference to PLL (not available when in differential mode).

LVL

Status of selected reference (status of differential reference);

active low.

LVL

Status of unselected reference (not available in differential mode);

active low.

LVL

Status of REF1 frequency (active low).

LVL

Status of REF2 frequency (active low).

LVL

(Status of REF1 frequency) AND (status of REF2 frequency).

LVL

(DLD) AND (status of selected reference) AND (status of VCO).

LVL

Status of VCO frequency (active low).

LVL

Selected reference (low = REF2, high = REF1).

LVL

DLD; active low.

LVL

Holdover active (active low).

LVL

LD pin comparator output (active low).

01C

[7]

Disable

switchover

deglitch

Disables or enables the switchover deglitch circuit.

[7] = 0; enable the switchover deglitch circuit (default).

[7] = 1; disable the switchover deglitch circuit.

01C

[6]

Select REF2

If Register 0x01C[5] = 0, selects the reference for PLL when in manual; register selected reference control.

[6] = 0; select REF1 (default).

[6] = 1; select REF2.

01C

[5]

Use REF_SEL

If Register 0x01C[4] = 0 (manual), sets the method of PLL reference selection.

[5] = 0; use Register 0x01C[6] (default).

[5] = 1; use REF_SEL pin.

01C

[4]

Enable

automatic

reference

switchover

Automatic or manual reference switchover. Single-ended reference mode must be selected by

[4] = 0; manual reference switchover (default).

[4] = 1; automatic reference switchover.

Setting this bit also powers on REF1 and REF2 and overrides the settings in Register 0x01C[2:1].

01C

[3]

Stay on REF2

Stays on REF2 after switchover.

[3] = 0; return to REF1 automatically when REF1 status is good again (default).

[3] = 1; stay on REF2 after switchover. Do not automatically return to REF1.

01C

[2]

Enable REF2

This bit turns the REF2 power on. This bit is overridden when automatic reference switchover is enabled.

[2] = 0; REF2 power off (default).

[2] = 1; REF2 power on.

01C

[1]

Enable REF1

This bit turns the REF1 power on. This bit is overridden when automatic reference switchover is enabled.

[1] = 0; REF1 power off (default).

[1] = 1; REF1 power on.

01C

[0]

Enable

differential

reference

Selects the PLL reference mode, differential or single-ended.

[0] = 0; single-ended reference mode (default).

[0] = 1; differential reference mode.

AD9520-2/PCBZ 数据表(PDF) 73 Page - Analog Devices

AD9520-2/PCBZ 数据表(HTML) 73 Page - Analog Devices

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

数据表下载