CD74HCT7046A中文资料带 VCO 和锁定检测器的高速 CMOS 逻辑锁相环数据手册TI规格书

描述 Description

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.

特性 Features

• Center Frequency of 18MHz (Typ) at VCC = 5V, Minimum Center Frequency of 12MHz at VCC = 4.5V
• Edge-Triggered JK Flip-Flop
• VCO-Inhibit Control for ON/OFF Keying and for Low Standby Power Consumption
• Zero Voltage Offset Due to Op-Amp Buffer
• Digital Section...2V to 6V
• Bus Driver Outputs...15 LSTTL Loads
• Balanced Propagation Delay and Transition Times
• HC Types
• High Noise Immunity: NIL = 30%, NIH = 30% of VCC at VCC = 5V
• Direct LSTTL Input Logic Compatibility, VIL = 0.8V (Max), VIH = 2V (Min)
• Applications
• Frequency Synthesis and Multiplication
• Tone Decoding
• Voltage-to-Frequency Conversion
• Related Literature
- AN8823, CMOS Phase-Locked-Loop Application Using the CD74HC/HCT7046A and CD74HC/HCT7046A