MC145574APB Freescale Semiconductor, MC145574APB Datasheet - Page 122

• Manufacturer Part Number: MC145574APB
• Description: IC TRANSCEIVER ISDN 32-LQFP
• Manufacturer: Freescale Semiconductor
• Type: Transceiverr

Specifications of MC145574APB

• Voltage - Supply: 4.75 V ~ 5.25 V
• Mounting Type: Surface Mount
• Package / Case: 32-LQFP
• Number Of Line Interfaces: 1
• Control Interface: HDLC
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Number Of Drivers/receivers: -
• Protocol: -
• Lead Free Status / Rohs Status: Not Compliant

17–2
17.2.3
17.2.4
Absolute Minimum Power
In this mode, the device is forced into the absolute minimum power state from which it cannot be
activated from the S/T–interface. All internal circuits are disabled, including the XTAL oscillator, and
only the SCP interface remains functional. All possible power consumption in the Tx and Rx analog
circuitry is blocked.
In IDL2/SCP mode, this power mode is entered/exited by writing to the NR0(1) register in the SCP.
In GCI mode, this power reduction mode is not available.
The characteristics of this mode are identical to that in the MC145474 except for the XTAL oscillator,
which is disabled in the MC145574.
Sleep
In this mode, the device is in a power conservation mode where all possible power consuming circuitry
is switched off, including the XTAL OSC.
In SCP mode, the sleep mode is enabled by writing to OR8(0). When the device goes into the sleep
state, only the SCP and an energy detector with receiver remain operational.
In GCI mode, the sleep mode is enabled by default. The sleep mode can be disabled by writing the
OR8(0) via the Monitor channel. When the device goes into the sleep state, only the GCI interface
and an energy detector in the receiver remains operational. Sleep mode is not available with NT master
GCI/SCP configuration.
In both SCP and GCI modes, the device will enter the sleep state (assuming sleep mode is enabled)
when the MC145574 detects no activity on the S/T–interface and is in the deactivated state. A timer
is then enabled which will cause the MC145574 to enter the sleep state after a period of 2 ms.
The sleep state is exited when a signal is detected on the S/T–interface. In this case, the device exits
sleep mode and tries to synchronize to the signal. If successful, the device activates in the normal
function. The sleep state can also be exited by writing an activate request via the SCP. This cause
the device to exit the sleep state and attempt to activate in the normal function.
In GCI slave mode, the sleep state is exited by using the AR command on the C/I channel.
In GCI master mode (TE master only), the sleep mode is exited by first pulling the D in pin low to request
that the GCI clock starts, and then issuing the TIM command (if only the GCI interface is to be activated),
or by issuing the AR command if an activation is to be attempted.
When the MC145574 enters the sleep state, the crystal oscillator is disabled, i.e., stopped.
MC145574
MOTOROLA