High Speed CMOS Logic Phase-Locked Loop with VCO and Lock Detector



Product details


Technology Family HCT Bits (#) 1 VCC (Min) (V) 4.5 VCC (Max) (V) 5.5 Input type TTL Output type CMOS IOL (Max) (mA) 4 IOH (Max) (mA) -4 open-in-new Find other Phase-locked-loop (PLL)/oscillator

Package | Pins | Size

PDIP (N) 16 181 mm² 19.3 x 9.4 SOIC (D) 16 59 mm² 9.9 x 6 open-in-new Find other Phase-locked-loop (PLL)/oscillator


  • Center Frequency of 18MHz (Typ) at VCC = 5V, Minimum Center Frequency of 12MHz at VCC = 4.5V
  • Choice of Two Phase Comparators
    • Exclusive-OR
    • Edge-Triggered JK Flip-Flop
  • Excellent VCO Frequency Linearity
  • VCO-Inhibit Control for ON/OFF Keying and for Low Standby Power Consumption
  • Minimal Frequency Drift
  • Zero Voltage Offset Due to Op-Amp Buffer
  • Operating Power-Supply Voltage Range
    • VCO Section...3V to 6V
    • Digital Section...2V to 6V
  • Fanout (Over Temperature Range)
    • Standard Outputs...10 LSTTL Loads
    • Bus Driver Outputs...15 LSTTL Loads
  • Wide Operating Temperature Range... –55°C to 125°C
  • Balanced Propagation Delay and Transition Times
  • Significant Power Reduction Compared to LSTTL Logic ICs
  • HC Types
    • 2V to 6V Operation
    • High Noise Immunity: NIL = 30%, NIH = 30% of VCC at VCC = 5V
  • HCT Types
    • 4.5V to 5.5V Operation
    • Direct LSTTL Input Logic Compatibility, VIL = 0.8V (Max), VIH = 2V (Min)
    • CMOS Input Compatibility, Il ≤ 1µA at VOL, VOH
  • Applications
    • FM Modulation and Demodulation
    • Frequency Synthesis and Multiplication
    • Frequency Discrimination
    • Tone Decoding
    • Data Synchronization and Conditioning
    • Voltage-to-Frequency Conversion
    • Motor-Speed Control
    • Related Literature
      • AN8823, CMOS Phase-Locked-Loop Application Using the CD74HC/HCT7046A and CD74HC/HCT7046A
open-in-new Find other Phase-locked-loop (PLL)/oscillator


The CD74HC7046A and CD74HCT7046A high-speed silicon-gate CMOS devices, specified in compliance with JEDEC Standard No. 7A, are phase-locked-loop (PLL) circuits that contain a linear voltage-controlled oscillator (VCO), two-phase comparators (PC1, PC2), and a lock detector. A signal input and a comparator input are common to each comparator. The lock detector gives a HIGH level at pin 1 (LD) when the PLL is locked. The lock detector capacitor must be connected between pin 15 (CLD) and pin 8 (Gnd). For a frequency range of 100kHz to 10MHz, the lock detector capacitor should be 1000pF to 10pF, respectively.

The signal input can be directly coupled to large voltage signals, or indirectly coupled (with a series capacitor) to small voltage signals. A self-bias input circuit keeps small voltage signals within the linear region of the input amplifiers. With a passive low-pass filter, the 7046A forms a second-order loop PLL. The excellent VCO linearity is achieved by the use of linear op-amp techniques.

open-in-new Find other Phase-locked-loop (PLL)/oscillator

Technical documentation

= Top documentation for this product selected by TI
No results found. Please clear your search and try again. View all 15
Type Title Date
* Datasheet CD74HC7046A, CD74HCT7046A datasheet (Rev. C) Oct. 16, 2003
Selection guide Logic Guide (Rev. AB) Jun. 12, 2017
Application note Implications of Slow or Floating CMOS Inputs (Rev. D) Jun. 23, 2016
Application note Understanding and Interpreting Standard-Logic Data Sheets (Rev. C) Dec. 02, 2015
Technical articles Failure to lock: Why wideband PLL frequency synthesizers lose lock Mar. 22, 2013
User guide LOGIC Pocket Data Book (Rev. B) Jan. 16, 2007
Application note Semiconductor Packing Material Electrostatic Discharge (ESD) Protection Jul. 08, 2004
User guide Signal Switch Data Book (Rev. A) Nov. 14, 2003
More literature Logic Cross-Reference (Rev. A) Oct. 07, 2003
Application note CMOS Phase-Locked-Loop Applications (Rev. B) Sep. 19, 2002
Application note TI IBIS File Creation, Validation, and Distribution Processes Aug. 29, 2002
Application note CMOS Power Consumption and CPD Calculation (Rev. B) Jun. 01, 1997
Application note Designing With Logic (Rev. C) Jun. 01, 1997
Application note SN54/74HCT CMOS Logic Family Applications and Restrictions May 01, 1996
Application note Using High Speed CMOS and Advanced CMOS in Systems With Multiple Vcc Apr. 01, 1996

Design & development

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Hardware development

document-generic User guide
This EVM is designed to support any logic device that has a D, DW, DB, NS, PW, P, N, or DGV package in a 14 to 24 pin count.
  • Board design allows for versatility in evaluation
  • Supports a wide-range of logic devices

CAD/CAE symbols

Package Pins Download
PDIP (N) 16 View options
SOIC (D) 16 View options

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