STOTG04ES

Block description

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6.6

Control logic

some glue logic.

6.7

Modes of operation

The STOTG04ES can operate in two different power modes and in three operating modes. They can be

controlled by logic signals and control registers.

6.7.1

Power modes

To reduce power consumption when there is no need for the USB function, the STOTG04 implements

power-down mode. In this mode, the power consumption is strongly reduced. Power mode of the device

can be controlled by bit suspend of the Control Register 1 or/and the SUSPEND pin as can be seen in

table 8).

Table 8.

Power modes

Although in power down mode all analog blocks should be switched off, some of them could be turned on

by bits in the control registers having higher priority than suspend bit. In order to obtain minimum power

consumption in power down mode the device must be configured has shown in Table 9. The digital part is

fully static so that it almost does not consume power. All of the interrupts (except BDIS_ACON) are fully

Table 9.

Power down mode setup

X = Don’t care

- = Reserved

Bit order: 0...7

6.7.2

USB Modes

The STOTG04ES transceiver has two basic USB operational modes. These modes define how the digital

IO pins of the transceiver will be used. Independently of USB operating mode, some signals always have

the same function (see Table 10).

Table 10.

Digital interface signals

SUSPEND BIT

SUSPEND PIN

Power Mode

0X

normal operation

X0

1

1

power-down

SUSPEND BIT

SUSPEND PIN

Control register 1

Control register 2

Control register 3

1

1

X1X0XX0-

00XX00X0

-XXXX0XX

Signal

Function

RCV

Differential receiver output

VP

D+ single-ended receiver output

VM

D- single-ended receiver output

OE_TP_INT/

Output enable signal of the differential driver