Micrel, Inc.
MIC2555
USB mode: uart_en = 0
suspend
dat_se0
OE_INT/
RCV
DIFF
DIFF
Z
DAT_VP
TX data
SE_DP
TX data
DIFF
SE0_VM
TX data
SE_DM
TX data
RX_SE0
SE_DM
RX_SE0
D+
D-
0
0
0
0
1
1
0
0
1
1
0
1
0
1
0
1
1
1
DAT_VP
RX data
TX_DAT
RX data
RX data
RX data
SE0_VM
RX data
TX_SE0
RX data
RX data
RX data
Z
Z
SE_DP
SE_DP
Z
DIFF
= Differential receiver output
RX_SE0 = not (SE_DP) and not (SE_DM)
TX_DAT = DAT_VP and not (SE0_VM)
TX_SE0 = not (DAT_VP) and not (SE0_VM)
= Tri-State
Z
USB Transmit Operation
USB Mode
Inputs
Outputs
DAT_VP_RX
SE0_VM_TX
D+
0
D-
1
0
0
0
0
0
1
1
RCV
unused
unused
unused
unused
undefined
1
0
1
0
1
0
1
0
1
0
0
1
1
0
0
1
1
1
DAT-SE0
VP-VM
0
0
0
1
0
0
1
undefined
The transceiver receives USB data from D+, D- lines when:
Conditions:
Uart_en = 0
OE_INT/ = 0
Operation of the DAT_VP_RX, SE0_VM_TX and RCV pins during receive is shown on the following page.
M9999-121406
December 2006
15
MICREL [ MICREL SEMICONDUCTOR ]
