ZHCSC07E December 2013 – March 2019 DLPC2607
PRODUCTION DATA.
请参考 PDF 数据表获取器件具体的封装图。
The device requires an external reference clock to feed its internal PLL. This reference may be supplied by a crystal or oscillator. For flexibility, the DLPC2607 device accepts either of two reference clock frequencies (see Table 5), but both must have a maximum frequency variation of 200 ppm (including aging, temperature, and trim component variation). When a crystal is used, the configuration requires several discrete components, as shown in Figure 11.
PARAMETER | NOM | UNIT |
---|---|---|
PLL_REFCLK_I TO GND capacitance | 4.5 | pF |
PLL_REFCLK_O TO GND capacitance | 4.5 | pF |
PARAMETER | RECOMMENDED | UNIT |
---|---|---|
Crystal circuit configuration | Parallel resonant | |
Crystal type | Fundamental (first harmonic) | |
Crystal nominal frequency (See TSTPT_6 in the Pin Functions table) | 16.667 or 8.333 | MHz |
Crystal frequency tolerance (including accuracy, temperature, aging, and trim sensitivity) | ±200 | PPM |
Crystal drive level | 100 max | µW |
Crystal equivalent series resistance (ESR) | 80 max | Ω |
Crystal load | 12 | pF |
RS drive resistor (nominal) | 100 | Ω |
RFB feedback resistor (nominal) | 1 | MΩ |
CL1 external crystal load capacitor | See Figure 11 | pF |
CL2 external crystal load capacitor | See Figure 11 | pF |
PCB layout | TI recommends a ground isolation ring around the crystal |
If an external oscillator is used, then the oscillator output must drive the PLL_REFCLK_I pin on the DLPC2607 ASIC. Leave the PLL_REFCLK_O pins unconnected. An oscillator that provides a spread-spectrum clock reduces EMI.
NOTE
The DLPC2607 device accepts between 0% to –2% spreading (that is, down spreading only) with a modulation frequency between 20 kHz and 65 kHz and a triangular waveform.
Similar to the crystal option, the oscillator input frequency is limited to 16.667 or 8.333 MHz. To configure the DLPC2607 device to accept the 8.333-MHz reference clock option, an external pullup resistor to VCC18 must be applied to the TSTPT (6) pin. To configure the DLPC2607 device to accept the 16.667-MHz reference clock option, leave the TSTPT (6) pin unconnected.
It is assumed that the external crystal or oscillator stabilizes within 50 ms after stable power is applied.