Datasheet

Data Sheet AD9548

Rev. E | Page 73 of 112

The IRQ mask register bits form a one-to-one correspondence with the bits of the IRQ monitor register (Address 0x0D02 to

Address 0x0D09). When set to Logic 1, the IRQ mask bits enable the corresponding IRQ monitor bits to indicate an IRQ event. The

default for all IRQ mask bits is Logic 0, which prevents the IRQ monitor from detecting any internal interrupts.

Table 50. IRQ Mask for SYSCLK

Address Bits Bit Name Description

0x0209 [7:6] Unused

[5]

SYSCLK unlocked

Enables IRQ for indicating a SYSCLK PLL state transition from locked to unlocked

[4] SYSCLK locked Enables IRQ for indicating a SYSCLK PLL state transition from unlocked to locked

[3:2] Unused

[1] SYSCLK Cal complete Enables IRQ for indicating that SYSCLK calibration has completed

[0] SYSCLK Cal started Enables IRQ for indicating that SYSCLK calibration has begun

Table 51. IRQ Mask for Distribution Sync, Watchdog Timer, and EEPROM

Address Bits Bit Name Description

0x020A [7:4] Unused

[3] Distribution sync Enables IRQ for indicating a distribution sync event

[2]

Watchdog timer

Enables IRQ for indicating expiration of the watchdog timer

[1] EEPROM fault Enables IRQ for indicating a fault during an EEPROM load or save operation

[0] EEPROM complete Enables IRQ for indicating successful completion of an EEPROM load or save

operation

Table 52. IRQ Mask for the Digital PLL

Address Bits Bit Name Description

0x020B [7] Switching Enables IRQ for indicating that the DPLL is switching to a new reference

[6] Closed Enables IRQ for indicating that the DPLL has entered closed-loop operation

[5] Freerun Enables IRQ for indicating that the DPLL has entered free-run mode

[4] Holdover Enables IRQ for indicating that the DPLL has entered holdover mode

[3] Freq unlocked Enables IRQ for indicating that the DPLL lost frequency lock

[2] Freq locked Enables IRQ for indicating that the DPLL has acquired frequency lock

[1] Phase unlocked Enables IRQ for indicating that the DPLL lost phase lock

[0] Phase locked Enables IRQ for indicating that the DPLL has acquired phase lock

Table 53. IRQ Mask for History Update, Frequency Limit, and Phase Slew Limit

Address Bits Bit Name Description

0x020C [7:5] Unused

[4] History updated Enables IRQ for indicating the occurrence of a tuning word history update

[3] Frequency unclamped Enables IRQ for indicating a state transition frequency limiter from clamped to

unclamped

[2] Frequency clamped Enables IRQ for indicating a state transition of the frequency limiter from

unclamped to clamped

[1] Phase slew unlimited Enables IRQ for indicating a state transition of the phase slew limiter from slew

limiting to not slew limiting

[0] Phase slew limited Enables IRQ for indicating a state transition of the phase slew limiter from not slew

limiting to slew limiting