Overview
The LMX2485ESQ/NOPB is a high-performance, low-power delta-sigma fractional-N PLL with an auxiliary integer-N PLL, designed and manufactured by Texas Instruments. This device is fabricated using Texas Instruments' advanced process technology, ensuring high reliability and performance. It is particularly suited for applications requiring fine frequency resolution, low spurs, and fast programming speed. The LMX2485ESQ/NOPB is ideal for direct digital modulation applications and is available in a 24-lead WQFN package.
Key Specifications
| Parameter | Value |
|---|---|
| Package Type | WQFN (RTW) |
| Pins | 24 |
| Operating Temperature Range (°C) | -40 to 85 |
| Minimum Output Frequency | 50 MHz |
| Maximum Output Frequency | 3000 MHz |
| Minimum Operating Supply Voltage | 2.5 V |
| Maximum Operating Supply Voltage | 3.6 V |
| Maximum Supply Current | 5 mA |
| Dimensions | 4 x 4 x 0.8 mm |
| RF PLL Frequency Range | 50 MHz to 3.0 GHz (LMX2485E), 500 MHz to 3.0 GHz (LMX2485) |
| IF PLL Frequency Range | 75 MHz to 800 MHz |
Key Features
- Quadruple Modulus Prescaler for Lower Divides
- RF PLL: 8/9/12/13 or 16/17/20/21
- IF PLL: 8/9 or 16/17
- Advanced Delta-Sigma Fractional Compensation
- 12-Bit or 22-Bit Selectable Fractional Modulus
- Up to 4th Order Programmable Delta-Sigma Modulator
- Fastlock / Cycle Slip Reduction With Integrated Time-Out Counter
- Digital Lock Detect Output
- Hardware and Software Power-Down Control
- On-Chip Input Frequency Doubler
- RF Phase Detector Frequency up to 50 MHz
Applications
- Cellular Phones and Base Stations
- Direct Digital Modulation Applications
- Satellite and Cable TV Tuners
- WLAN Standards
Q & A
- What is the operating temperature range of the LMX2485ESQ/NOPB?
The operating temperature range is -40°C to 85°C.
- What are the minimum and maximum output frequencies of the LMX2485ESQ/NOPB?
The minimum output frequency is 50 MHz, and the maximum output frequency is 3000 MHz.
- What is the package type and pin count of the LMX2485ESQ/NOPB?
The package type is WQFN (RTW) with 24 pins.
- What are the voltage and current specifications for the LMX2485ESQ/NOPB?
The minimum operating supply voltage is 2.5 V, the maximum operating supply voltage is 3.6 V, and the maximum supply current is 5 mA.
- What are the key features of the LMX2485ESQ/NOPB's delta-sigma modulator?
The delta-sigma modulator is programmable up to fourth order, and it features advanced delta-sigma fractional compensation and selectable fractional modulus (12-bit or 22-bit).
- What are some of the applications for the LMX2485ESQ/NOPB?
Applications include cellular phones and base stations, direct digital modulation applications, satellite and cable TV tuners, and WLAN standards.
- How does the LMX2485ESQ/NOPB handle power management?
The device features hardware and software power-down control, allowing for efficient power management.
- What is the significance of the Fastlock feature in the LMX2485ESQ/NOPB?
The Fastlock feature, along with cycle slip reduction and an integrated time-out counter, enhances the lock time performance of the device.
- How is the frequency programming done in the LMX2485ESQ/NOPB?
Serial data for programming is transferred through a three-line, high-speed (20-MHz) MICROWIRE interface, allowing for fast programming speed and single-word write to change the frequency.
- What are the dimensions of the LMX2485ESQ/NOPB package?
The dimensions are 4 x 4 x 0.8 mm.
