Overview
The CDCM1802RGTTG4, produced by Texas Instruments, is a clock buffer with programmable divider capabilities. This device is designed to distribute one differential clock input to one LVPECL (Low-Voltage Positive Emitter-Coupled Logic) differential clock output and one LVCMOS (Low-Voltage Complementary Metal-Oxide-Semiconductor) single-ended output. It is specifically engineered for driving 50-Ω transmission lines, making it suitable for high-speed clock distribution applications.
The CDCM1802 features a wide common-mode range and provides a VBB bias voltage output for single-ended input signals, enhancing its versatility in various clocking scenarios. The device operates over a temperature range of -40°C to 85°C, ensuring reliability in diverse environmental conditions.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Package | 16-Pin VQFN (RGT) | |
| Operating Temperature Range | -40 to 85 | °C |
| Supply Voltage (VDD) | 3.0 to 3.6 | V |
| LVPECL Signaling Rate | Up to 800 MHz | |
| LVCMOS Signaling Rate | Up to 200 MHz | |
| Output Skew (LVCMOS to LVPECL) | 1.6 ns | |
| Receiver Input Threshold | ±75 mV | |
| Output Capacitance | 2 pF | |
| Junction-to-Ambient Thermal Resistance (RθJA) | 48.4 °C/W |
Key Features
- Distributes one differential clock input to one LVPECL differential clock output and one LVCMOS single-ended output.
- Programmable output divider for both LVPECL and LVCMOS outputs, allowing division by 1, 2, 4, and 8.
- 1.6-ns output skew between LVCMOS and LVPECL transitions to minimize noise impact during signal transitions.
- 3.3-V power supply with 2.5-V functional capability.
- Differential input stage with wide common-mode range and VBB bias voltage output for single-ended input signals.
- Two control pins (S0 and S1) and an enable pin (EN) for selecting different output mode settings and enabling/disabling outputs.
- 16-Pin VQFN package with a size of 3.00 mm × 3.00 mm.
Applications
- Networking and Data Communications: Ideal for high-speed clock distribution in network equipment and data communication systems.
- Medical Imaging: Suitable for medical imaging devices that require precise clock signals.
- Portable Test and Measurement: Used in portable test and measurement equipment where high-speed clocking is necessary.
- High-end A/V: Applied in high-end audio and video systems requiring accurate clock signals.
Q & A
- What is the primary function of the CDCM1802?
The CDCM1802 is a clock buffer that distributes one differential clock input to one LVPECL differential clock output and one LVCMOS single-ended output.
- What are the signaling rates for LVPECL and LVCMOS outputs?
The signaling rates are up to 800 MHz for LVPECL and up to 200 MHz for LVCMOS.
- How does the CDCM1802 minimize noise during signal transitions?
The CDCM1802 minimizes noise by introducing a 1.6-ns output skew between LVCMOS and LVPECL transitions.
- What is the operating temperature range of the CDCM1802?
The operating temperature range is from -40°C to 85°C.
- How are the output modes selected on the CDCM1802?
The output modes are selected using two control pins (S0 and S1) and an enable pin (EN).
- What is the purpose of the VBB output pin?
The VBB output pin provides a common-mode voltage reference for single-ended input signals.
- What is the package type and size of the CDCM1802?
The CDCM1802 comes in a 16-Pin VQFN package with a size of 3.00 mm × 3.00 mm.
- Can the CDCM1802 be used in high-speed applications?
Yes, the CDCM1802 is designed for high-speed clock distribution applications.
- What are some common applications of the CDCM1802?
Common applications include networking and data communications, medical imaging, portable test and measurement, and high-end A/V systems.
- How does the CDCM1802 handle thermal management?
The CDCM1802 has specified thermal metrics, including a junction-to-ambient thermal resistance (RθJA) of 48.4 °C/W.
