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Linduino
Features
- Low Noise Fractional-N PLL with Integrated VCO
- No Δ-Σ Modulator Spurs
- 18-Bit Fractional Denominator
- –226 dBc/Hz Normalized In-Band Phase Noise Floor
- –274 dBc/Hz Normalized In-Band 1/f Noise
- –157 dBc/Hz Wideband Output Phase Noise Floor
- Excellent Integer Boundary Spurious Performance
- Output Divider (1 to 6, 50% Duty Cycle)
- Output Buffer Muting
- Reference Input Frequency Up to 425MHz
- Fast Frequency Switching
- FracNWizard™ Software Design Tool Support
Typical Application
Description
The LTC®6948 is a high performance, low noise, 6.39GHz phase-locked loop (PLL) with a fully integrated VCO, including a reference divider, phase-frequency detector (PFD), ultralow noise charge pump, fractional feedback divider, and VCO output divider.
The fractional divider uses an advanced, 4th order ΔΣ modulator which provides exceptionally low spurious levels. This allows wide loop bandwidths, producing extremely low integrated phase noise values.
The programmable VCO output divider, with a range of 1 through 6, extends the output frequency range.
4x5 QFN-28
Package Variations and Pricing
| Part Number | Package | Pins | Temp | Price (1-99) |
Price (1k)* |
|---|---|---|---|---|---|
| LTC6948IUFD-1#PBF | QFN | 28 | I | $10.36 | $7.25 |
| LTC6948IUFD-1#TRPBF | QFN | 28 | I | $7.31 | |
| LTC6948IUFD-2#PBF | QFN | 28 | I | $10.36 | $7.25 |
| LTC6948IUFD-2#TRPBF | QFN | 28 | I | $7.31 | |
| LTC6948IUFD-3#PBF | QFN | 28 | I | $10.36 | $7.25 |
| LTC6948IUFD-3#TRPBF | QFN | 28 | I | $7.31 | |
| LTC6948IUFD-4#PBF | QFN | 28 | I | $10.36 | $7.25 |
| LTC6948IUFD-4#TRPBF | QFN | 28 | I | $7.31 |
Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.
| Part Number | Description | Price | Documentation |
|---|---|---|---|
| DC1959A-B | LTC6948-2 Demo Board | Ultralow Noise and Spurious 513MHz to 4.91GHz Frac-N Synthesizer with Integrated VCO, (Req DC590) | $125.00 | |
| DC1959A-C | LTC6948-3 Demo Board| Ultralow Noise and Spurious 640MHz to 5.79GHz Frac-N Synthesizer with Integrated VCO, (Req DC590) | $125.00 | |
| DC1959B-A | LTC6948-1 Demo Board | Ultralow Noise and Spurious 373MHz to 3.74GHz Frac-N Synthesizer with Integrated VCO, (Req DC590 or DC2026) | $125.00 | |
| DC1959B-D | LTC6948-4 Demo Board | Ultralow Noise and Spurious 700MHz to 6.39GHz Frac-N Synthesizer with Integrated VCO, (Req DC590 or DC2026) | $125.00 |
Companion Boards
| Part Number | Description | Price | Documentation |
|---|---|---|---|
| DC2026C | Linduino One Isolated USB Demo Board: An Arduino- and QuikEval-Compatible Code Development Platform | $75.00 | |
| DC2429A | LT3042 PLL/VCO Supply and Reference Board | $150.00 | |
| DC590B | Isolated USB Serial Controller for Linear Technology QuikEval-Compatible Demo Boards | $50.00 |