74HCT7046A datasheet(3/38 Pages) PHILIPS

부품명	74HCT7046A

상세설명	Phase-locked-loop with lock detector

Download	38 Pages

Scroll/Zoom	100%

제조업체	PHILIPS [NXP Semiconductors]

홈페이지	http://www.nxp.com

Logo

3 / 38 page

December 1990

3

Philips Semiconductors

Product speciﬁcation

Phase-locked-loop with lock detector

74HC/HCT7046A

waveforms for the PC1 loop locked at

fo are shown in Fig.7.

The frequency capture range (2fc) is

defined as the frequency range of

input signals on which the PLL will

lock if it was initially out-of-lock. The

frequency lock range (2fL) is defined

as the frequency range of input

signals on which the loop will stay

locked if it was initially in lock. The

capture range is smaller or equal to

the lock range.

With PC1, the capture range depends

on the low-pass filter characteristics

and can be made as large as the lock

range. This configuration retains lock

even with very noisy input signals.

Typical behaviour of this type of

phase comparator is that it can lock to

input frequencies close to the

harmonics of the VCO centre

frequency.

Phase comparator 2 (PC2)

This is a positive edge-triggered

phase and frequency detector. When

the PLL is using this comparator, the

loop is controlled by positive signal

transitions and the duty factors of

SIGIN and COMPIN are not important.

PC2 comprises two D-type flip-flops,

control-gating and a 3-state output

stage. The circuit functions as an

up-down counter (Fig.5) where SIGIN

causes an up-count and COMPIN a

down-count. The transfer function of

PC2, assuming ripple (fr =fi) is

suppressed,

is:

where VDEMOUT is the demodulator

output at pin 10;

VDEMOUT =VPC2OUT (via low-pass

filter).

V

DEMOUT

V

CC

4

π

-----------

φ

SIGIN

φ

COMPIN

–

()

=

The phase comparator gain is:

VDEMOUT is the resultant of the initial

phase differences of SIGIN and

COMPIN as shown in Fig.8. Typical

waveforms for the PC2 loop locked at

fo are shown in Fig.9.

When the frequencies of SIGIN and

COMPIN are equal but the phase of

SIGIN leads that of COMPIN, the

p-type output driver at PC2OUT is held

“ON” for a time corresponding to the

phase difference (

φ

DEMOUT). When

the phase of SIGIN lags that of

COMPIN, the n-type driver is held

“ON”.

When the frequency of SIGIN is higher

than that of COMPIN, the p-type

output driver is held “ON” for most of

the input signal cycle time, and for

the remainder of the cycle both n and

p- type drivers are “OFF” (3-state). If

the SIGIN frequency is lower than the

COMPIN frequency, then it is the

n-type driver that is held “ON” for

most of the cycle. Subsequently, the

voltage at the capacitor (C2) of the

low-pass filter connected to PC2OUT

varies until the signal and comparator

inputs are equal in both phase and

frequency. At this stable point the

voltage on C2 remains constant as

the PC2 output is in 3-state and the

VCO input at pin 9 is a high

impedance.

Thus, for PC2, no phase difference

exists between SIGIN and COMPIN

over the full frequency range of the

VCO. Moreover, the power

dissipation due to the low-pass filter is

reduced because both p and n-type

drivers are “OFF” for most of the

signal input cycle. It should be noted

that the PLL lock range for this type of

phase comparator is equal to the

capture range and is independent of

K

p

V

CC

4

π

----------- Vr

⁄

() .

=

the low-pass filter. With no signal

present at SIGIN the VCO adjusts, via

PC2, to its lowest frequency.

APPLICATIONS

• FM modulation and demodulation

• Frequency synthesis and

multiplication

• Frequency discrimination

• Tone decoding

• Data synchronization and

conditioning

• Voltage-to-frequency conversion

• Motor-speed control

유사한 부품 번호 - 74HCT7046A

제조업체	부품명	데이터시트	상세설명
NXP Semiconductors	74HCT7046A	453Kb / 38P	Phase-locked-loop with lock detector December 1990

More results

유사한 설명 - 74HCT7046A

제조업체	부품명	데이터시트	상세설명
NXP Semiconductors	74HC7046AN	453Kb / 38P	Phase-locked-loop with lock detector December 1990
Unisonic Technologies	U74HCT7046	408Kb / 16P	PHASE LOCKED LOOP WITH VCO & LOCK DETECTOR
Unisonic Technologies	U74HCT7046	408Kb / 16P	PHASE LOCKED LOOP WITH VCO & LOCK DETECTOR
Texas Instruments	CD74HC7046A	446Kb / 28P	[Old version datasheet] Phase-Locked Loop with VCO and Lock Detector
	CD74HC7046A	586Kb / 29P	[Old version datasheet] Phase-Locked Loop with VCO and Lock Detector
	CD74HC7046A	302Kb / 26P	[Old version datasheet] Phase-Locked Loop with VCO and Lock Detector
NXP Semiconductors	74HC4046A	467Kb / 34P	Phase-locked-loop with VCO 1997 Nov 25
NXP Semiconductors	HEF4046B	416Kb / 15P	Phase-locked loop January 1995
Z-Communications, Inc	PSA4230C-LF	93Kb / 2P	PHASE LOCKED LOOP
Z-Communications, Inc	PSN1100A	74Kb / 2P	PHASE LOCKED LOOP

More results

74HCT7046A 데이터시트(PDF) 3 Page - NXP Semiconductors

74HCT7046A 데이터시트(HTML) 3 Page - NXP Semiconductors

유사한 부품 번호 - 74HCT7046A

유사한 설명 - 74HCT7046A

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

데이터시트 다운로드

링크 URL