[AK1542A]
5. Reference Input
The reference input could be set to a dividing number in the range of 4 to 16383 using {R[13:0]}, which is a 14-bit address of
D[13:0] in <Address3>. A dividing number from 0 to 3 could not be set.
6. Prescaler and Swallow Counter
The dual modular prescaler (P/P+1) and the swallow counter are used to provide a large dividing ratio. The prescaler is set by
{PRE[1:0]}, which is a 2-bit address of D[15:14] in <Address3>.
{PRE[1:0]}=”00”: P=8, dividing ratio = 8/9
{PRE[1:0]}=”01”: P=16, dividing ratio = 16/17
{PRE[1:0]}=”10”: P=32, dividing ratio = 32/33
{PRE[1:0]}=”11”: Prohibited
7. Power Save Mode
AK1542A can be operated in the power-down or power-save mode as necessary by using the external control pins [PDN1]
and [PDN2].
Power On
See “13. Power-up Sequence”. It is necessary to bring [PDN1] to “High” first, then [PDN2]. Bringing [PDN1] and [PDN2]
to “High” simultaneously is prohibited.
Normal Operation
Pin name
State
PDN1
“Low”
“Low”
“High”
“High”
PDN2
“Low”
“High”
“Low”
“High”
Power down
Prohibited
Power save Mode
Normal Operation
Note 1) and Note 2)
Note 1) Register setup can be made 50µs after [PDN1] is set to “High”. The charge pump is in the Hi-Z state.
Note 2) Register settings are maintained when [PDN2] is set to “Low” during normal operation.
MS1399-E-00
2012/3
- 17 -
AKM [ ASAHI KASEI MICROSYSTEMS ]
