Rainbow Electronics ATA5812 - Manual (Page 44)

44
ATA5811/ATA5812 [Preliminary]
4689B–RKE–04/04
Pin VAUX To switch the transceiver from OFF to AUX mode, the voltage on pin VAUX V
VAUX
must
exceed 3.5 V (typically) (see Figure 32). If V
VAUX
exceeds 2 V (typically) pin N_RESET
is set to low, DVCC and the power supply for external devices VSOUT are switched on.
If V
VAUX
exceeds 3.5 V (typically) the status bit P_On_Aux is set to 1 and an interrupt is
issued.
After the voltage on pin VSOUT exceeds 2.3 V (typically) and the start-up time of the
XTO is elapsed the output clock on pin CLK is available. Because the enabling of pin
CLK is asynchronous the first clock cycle may be incomplete. N_RESET is set to high if
V
VSOUT
exceeds 2.38 V (typically) and the XTO is settled.
If the transceiver is in any active mode (Idle, TX, RX, RX_Polling), a positive edge on pin
VAUX and V
VAUX
> VS1 + 0.5 V sets P_On_Aux to 1. The state transition P_On_Aux 0
→
1 generates an interrupt. If P_On_Aux is still 1 during the positive edge on pin VAUX no
interrupt is issued. P_On_Aux and the interrupt is deleted after reading the status
register.
Figure 32. Timing Pin VAUX, Status Bit P_On_Aux
VSOUT
VAUX
N_RESET
IRQ
P_On_Aux
(Status Register)
CLK
OFF
Mode
AUX
Mode
DVCC
3.5 V (typ)
2.0 V (typ)
IDLE, TX, RX, RX Polling
Mode
V
Thres_1
= 2.3 V (typ)
V
VAUX
> VS1 + 0.5 V (typ) V
VAUX
> VS1 + 0.5 V (typ)
V
Thres_2
= 2.38 V (typ)