GPS Timing Solution

With the Dapu GPS timing solution, typical sensitivity is -165dBm for tracking and -148dBm for acquisition when combined with a recommended LNA. The high-stability TCXO enables reliable tracking of weak signals, while the SAW filter removes interference that could desensitize the receiver. Actual sensitivity depends on the specific GPS chipset, antenna quality, and PCB layout. For best sensitivity, follow the reference design closely, use proper matching networks, and minimize trace lengths between components. We can provide sensitivity testing support during your design validation phase.

Solution provides -165dBm tracking sensitivity. Follow reference design for optimal performance.

Yes, the Dapu GPS timing solution can be adapted for GLONASS and other GNSS systems. The TCXO frequency may need adjustment - GLONASS uses 1602MHz L1 frequency compared to GPS 1575.42MHz. Dapu offers GLONASS-specific SAW filters at 1602MHz. The TCXO stability requirements are similar across GNSS systems. For multi-GNSS receivers using the same reference clock, select a TCXO frequency compatible with all target systems (e.g., 26MHz works for most GPS/GLONASS chipsets). Contact our FAE team for multi-GNSS solution recommendations and frequency planning.

Use GLONASS-specific filter at 1602MHz. TCXO and other components are compatible.

The total power consumption of the Dapu GPS timing solution is typically under 5mA at 3.3V. The TCXO consumes approximately 2-3mA, depending on the specific model and voltage. The SAW filter is passive and consumes no power. Additional power will be consumed by the LNA (typically 3-5mA) and the GPS chipset itself. For battery-powered applications, the TCXO can be put in standby mode when GPS is not needed, reducing power to microamps. The 32.768kHz RTC crystal consumes negligible power (<1μA). Total solution power is competitive with designs using more expensive Japanese components.

Total solution <5mA. Use standby mode for battery-powered applications.

In most applications, additional shielding is not required for the Dapu GPS timing components. The SAW filter provides excellent rejection of out-of-band interference. However, in high-interference environments (e.g., near cellular transmitters or WiFi hotspots), consider placing the GPS RF section away from digital circuits and using ground planes for isolation. For smartphone applications where GPS and cellular share the same PCB, careful layout and the Dapu SAW filter are usually sufficient. If you experience interference issues, our FAE team can provide layout review and recommendations. Conducted EMI testing is recommended for certification.

Usually No shielding is needed. Follow good RF layout practices. Contact us for interference issues.

The Dapu RF1608-GPS SAW filter is internally matched to 50Ω and typically does not require external matching components for basic operation. However, for optimal performance and return loss, small series inductors (1-3nH) may be added on the input and output. The exact values depend on your PCB layout and trace lengths. The reference design includes recommended matching values for typical layouts. For custom layouts, we recommend S-parameter simulation and optimization. Our FAE team can review your layout and provide matching recommendations. The matching network should use high-Q components (COG ceramic or wirewound inductors) for best performance.

Usually No matching is needed. Add 1-3nH series inductors for optimal performance if desired.