Motorola SSETM 5000 service manual Audio and Power, Gcap II IC U501

Theory of Operation: VOCON Board 2-23

the Address(23:0) and Data(15:0) busses. The Flash memory contains host firmware, DSP firmware, and codeplug data with the exception of the tuning values that reside on the transceiver board’s serial EEPROM. The Flash memory IC is not field repairable.

The RESET_OUT of the dual-core processor is at a GPIO voltage logic level. Components D401 and R401 are used to convert the voltage down to a 1.8 V logic level, and this 1.8 V reset signal is fed to the Flash RESET pin. When this pin is asserted (active low logic), the Flash is in reset mode. In this mode, the internal circuitry powers down, and the outputs become high-impedance connections.

The Flash active-low chip select pin, EN_CE, is connected to the active-low CS0_N pin (CS0 test point) of the EIM. When the EN_CE is not asserted, the Flash is in standby mode, which reduces current consumption.

Several other active-low control pins determine what mode the Flash memory is in: the address valid pin ADV that is connected to the EIM LBA_N signal, the output enable pin EN_OE that is connected to the EIM OE_N signal, and the write enable pin EN_WE that is connected to the EIM EB1_N signal. For read mode, the ADV and EN_OE pins are asserted while the EN_WE pin is not asserted. When the EN_WE is asserted and the EN_OE pin is unasserted, the Flash operates in the write mode.

Figure 2-8illustrates the EIM and memory ICs block diagram.

RESET_OUT	Voltage		RESET
	Translator
LBA_N		CSO	ADV
CS0_N			EN_CE
EB1_N			EN_WE	Flash
OE_N			EN_OE	U402
		A(23:1)	A(22:0)
Dual-Core			D(15:0)
Processor
U401
A(23:0)		A(19:1)	A(18:0)
D(15:0)			D(15:0)
			EN_OE	SRAM
			LB
				U403
EB0_N
			UB
CS2_N		CS2	CS1
RW_N		R_W	EN_WE
				MAEPF-27414-A

Figure 2-8. Dual-Core Processor EIM and Memory Block Diagram

2.5.2.2 Audio and Power

The audio and power section contains the following components:

•GCAP II IC U501

•5 V regulator U505

•1.55 V regulator

•Audio pre-amplifier U502

•Audio power amplifier (PA) U503

•EEPOT U509

6881094C12-A November 11, 2004