Datasheet

MCP2221

DS20005292A-page 34  2014 Microchip Technology Inc.

5Bit 7 Don’t

care

Bit 6: Interrupt detection –

negative edge

If set, the interrupt detection flag will be set when a negative

edge occurs.

Bit 5: Interrupt detection –

positive edge

If set, the interrupt detection flag will be set when a positive edge

occurs.

Bit 4-3: ADC Reference Voltage 11 Reference voltage is 4.096V (only if V

DD is above this voltage).

10 Reference voltage is 2.048V

01 Reference voltage is 1.024V

00 Reference voltage is off (this is useful for the case in which the

ADC uses other reference than V

RM ADC; e.g., VDD)

Bit 2: ADC Reference Option 1 ADC reference voltage is VRM ADC

0 ADC reference voltage is V

Bit 1 Don’t

care

Bit 0 Don’t

care

6 Lower byte of the 16-bit USB VID

value.

7 Higher byte of the 16-bit USB

VID value.

8 Lower byte of the 16-bit USB PID

value.

9 Higher byte of the 16-bit USB

PID value.

10 USB power attributes This value will be used by the MCP2221’s USB Configuration

Descriptor (power attributes value) during the USB enumeration.

11 USB requested number of mA(s) The requested mA value during the USB enumeration will

represent the value at this index multiplied by 2.

12-19 8-bytes password (for Flash

modifications protection)

20-63 Don’t

care

TABLE 3-12: SUB-COMMAND STRUCTURE – WRITE CHIP SETTINGS SUB-COMMAND (CONTINUED)

Byte

Index

Function Description Value Effect