Introduction | GSM | DECT | PCS1900 |
PCS1900 Application Benchmarks
3. PCS1900 Low side injection
Figure 31. Application circuit, PCS1900 low side injection
This was simulated under the following conditions:-
| VCC | 3.0 V |
|---|---|
| V CP, V VCO | 4.6 V |
| Comparator frequency | 200 kHz |
| Prescaler divide ratio | 32/33 |
| Reference oscillator | 13 MHz, -3 dBm |
| RF out | 1767 MHz |
| Ambient temperature | 25°C |
| VCO | Murata MQE 520-1767(Kv = 31 MHz/V) |
Parts list:
| C1 | 100 pF |
|---|---|
| C2 | 10 nF |
| C3 | 10 µF |
| C4 | 100 pF |
| C5 | 33 pF |
| C6 | 33 pF |
| C10 | 100 pF |
| C11 | 10 µf |
| R3 | 0 Ω |
| R4 | 51 Ω |
| R5 | 47 κΩ |
| R6 | 47 κΩ |
| R7 | 47 κΩ |
| R8 | 18 Ω |
| R9 | 18 Ω |
| R10 | 18 Ω |
Loop filter:
| C7 | 3.3 NF |
|---|---|
| C8 | 33 NF |
| C9 | 220pF |
| R1 | 12 κΩ |
| R1 | 1.2 κΩ |
Test results
| Spurious performance | @Δf = 200 kHz | @Δf = 400 kHz | @Δf = 600 kHz | @Δf = 13 MHz |
|---|---|---|---|---|
| @1767 MHz | -65.6 dBc | -76.0 dBc | -83.5 dBc | -67 dBc |
| Phase noise performance | Measured value | Unit | Remarks |
|---|---|---|---|
| @1767 MHz | -71.8 | dBc/Hz | maximum within loop bandwidth = 12.5 kHz |
| Phase error | RMS value | Peak value | Unit |
|---|---|---|---|
| @1767 MHz | 2.3 | 6.5 | degrees |
| Hopping time | Measured value | Unit | Remarks |
|---|---|---|---|
| 1737 MHz → 1797 MHz | 466 | µs | |
| 1797 MHz → 1737 MHz | 466 | µs |
Figure 32 - Spurious performance at 1767 MHz -65.6 dBc
Figure 33 - Phase noise performance; C/N= -71.8 dBc/Hz, maximum within loop bandwidth
Figure 34 - Phase noise performance @ Δ f= 1MHz from carrier; C/N= -139.3 dBc/Hz « -146.3 dBm/Hz
Figure 35 - Phase noise performance @ Δ f= 10 MHz from carrier; C/N= -147.6 dBc/Hz « -154.6 dBm/Hz (close to measurable limit)
Figure 36 - Hopping time 466µs for frequency step 1737MHz → 1797MHz (Measurement triggered 100µs after PLL was programmed, therefore the marker readout shown on top is 100µs longer than the actual hopping time)
Figure 37 - Hopping time 466µs for frequency step 1797MHz → 1737MHz (Measurement triggered 100µs after PLL was programmed, therefore the marker readout shown on top is 100µs longer than the actual hopping time)
Figure 38 - Phase error @1767MHz, RMS value: 2.3°, peak value: 6.5°
Previous Page
1
2
3
4 
