ZHCSEA4C May 2015 – December 2020 ADS54J40
PRODUCTION DATA
The steps described in Table 9-1 are recommended as the power-up sequence with the ADS54J40 in 20X mode (LMFS = 8224).
STEP | SEQUENCE | DESCRIPTION | PAGE BEING PROGRAMMED | COMMENT |
---|---|---|---|---|
1 | Power-up the device | Bring up IOVDD to 1.15 V before applying power to DVDD. Bring up DVDD to 1.9 V, AVDD to 1.9 V, and AVDD3V to 3.0 V. | — | See the Power Sequencing and Initialization section for power sequence requirements. |
2 | Reset the device | Hardware reset | ||
Apply a hardware reset by pulsing pin 48 (low → high → low). | — | A hardware reset clears all registers to their default values. | ||
Register writes are equivalent to a hardware reset. | ||||
Write address 0-000h with 81h. | General register | Reset registers in the ADC and master pages of the analog bank. | ||
This bit is a self-clearing bit. | ||||
Write address 4-001h with 00h and address 4-002h with 00h. | Unused page | Clear any unwanted content from the unused pages of the JESD bank. | ||
Write address 4-003h with 00h and address 4-004h with 68h. | — | Select the main digital page of the JESD bank. | ||
Write address 6-0F7h with 01h for channel A. | Main digital page (JESD bank) |
Use the DIG RESET register bit to reset all pages in the JESD bank. | ||
This bit is a self-clearing bit. | ||||
Write address 6-000h with 01h, then address 6-000h with 00h. | Pulse the PULSE RESET register bit for channel A. | |||
3 | Performance modes | Write address 0-011h with 80h. | — | Select the master page of the analog bank. |
Write address 0-059h with 20h. | Master page (analog bank) |
Set the ALWAYS WRITE 1 bit. | ||
4 | Program desired registers for decimation options and JESD link configuration |
Default register writes for DDC modes and JESD link configuration (LMFS 8224). | ||
Write address 4-003h with 00h and address 4-004h with 69h. | — | Select the JESD digital page. | ||
Write address 6-000h with 80h. | JESD digital page (JESD bank) |
Set the CTRL K bit for both channels by programming K according to the SYSREF signal later on in the sequence. | ||
JESD link is configured with LMFS = 8224 by default with no decimation. | See Table 8-14 for configuring the JESD digital page registers for the desired LMFS and programming appropriate DDC mode. | |||
Write address 4-003h with 00h and address 4-004h with 6Ah. | — | Select the JESD analog page. | ||
JESD link is configured with LMFS = 8224 by default with no decimation. | JESD analog page (JESD bank) |
See Table 8-14 for configuring the JESD analog page registers for the desired LMFS and programming appropriate DDC mode. | ||
Write address 6-017h with 40h. | PLL reset. | |||
Write address 6-017h with 00h. | PLL reset clear. | |||
Write address 4-003h with 00h and address 4-004h with 68h. | — | Select the main digital page. | ||
JESD link is configured with LMFS = 8224 by default with no decimation. | Main digital page (JESD bank) |
See Table 8-14 for configuring the main digital page registers for the desired LMFS and programming appropriate DDC mode. | ||
Write address 6-000h with 01h and address 6-000h with 00h. | Pulse the PULSE RESET register bit. All settings programmed in the main digital page take effect only after this bit is pulsed. | |||
5 | Set the value of K and the SYSREF signal frequency accordingly | Write address 4-003h with 00h and address 4-004h with 69h. | — | Select the JESD digital page. |
Write address 6-006h with XXh (choose the value of K). | JESD digital page (JESD bank) |
See the SYSREF Signal section to choose the correct frequency for SYSREF. | ||
6 | JESD lane alignment | Pull the SYNCB pin (pin 63) low. | — | Transmit K28.5 characters. |
Pull the SYNCB pin high. | After the receiver is synchronized, initiate an ILA phase and subsequent transmissions of ADC data. |