PCM2704,PCM2705

PCM2706,PCM2707

SLES081A − JUNE 2003 – REVISED MAY 2004

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23

EXTERNAL ROM EXAMPLE

Here is an example of external ROM data, with an explanation of the example following the data.

0xBB, 0x08, 0x04, 0x27,

0x50, 0x72, 0x6F, 0x64, 0x75, 0x63, 0x74, 0x20, 0x73, 0x74, 0x72, 0x69, 0x6E, 0x67, 0x73, 0x2E,

0x56, 0x65, 0x6E, 0x64, 0x6F, 0x72, 0x20, 0x73, 0x74, 0x72, 0x69, 0x6E, 0x67, 0x73, 0x20, 0x61,

0x72, 0x65, 0x20, 0x70, 0x6C, 0x61, 0x63, 0x65, 0x64, 0x20, 0x68, 0x65, 0x72, 0x65, 0x2E, 0x20,

0x80,

0x7D,

0x0A, 0x93, 0x01

The data is stored beginning at address 0x00.

Vendor ID: 0x08BB

Device ID: 0x2704

Device string: Product strings. (16 bytes)

Vendor string: Vendor strings are placed here. (32 bytes, 31 visible characters are followed by 1 space)

bmAttribute: 0x80 (Bus-powered)

maxPower: 0x7D (250 mA)

Auxiliary HID usage ID: 0x0A, 0x93, 0x01 (AL A/V capture)

SERIAL PROGRAMMING INTERFACE (PCM2705/7)

The PCM2705/7 supports the serial programming interface (SPI) to program the descriptor and to set the HID state.

Descriptor data is described in the External ROM Descriptor section.

t(MCH)

50% of VDD

MS

t(MLS)

LSB

50% of VDD

50% of VDD

t(MCL)

t(MHH)

t(MLH)

t(MCY)

t(MDH)

t(MDS)

MC

MD

SYMBOL

PARAMETERS

MIN

TYP

MAX

UNITS

t(MCY)

MC pulse cycle time

100

ns

t(MCL)

MC low-level time

50

ns

t(MCH)

MC high-level time

50

ns

t(MHH)

MS high-level time

100

ns

t(MLS)

MS falling edge to MC rising edge

20

ns

t(MLH)

MS hold time

20

ns

t(MDH)

MD hold time

15

ns

t(MDS)

MD setup time

20

ns

Figure 26. SPI Timing Diagram