MIC2550 Datasheet, PDF (6/8 Pages) Micrel Semiconductor – Universal Serial Bus Transceiver Advance Information

MIC2550
OE# = 0 (Transmit):
Input
VP
VM
0
0
0
1
1
0
1
1
OE# = 1 (Receive):
Input
D+
D–
0
0
0
1
1
0
1
1
Output
D+
D–
0
0
0
1
1
0
1
1
Output
VP
VM
0
0
0
1
1
0
1
1
Table 1. Truth Table
RCV
X
0
1
X
RCV
X
0
1
X
Test Circuits
Device
Under
Test
Test
Point
24Ω
500Ω
50pF
V
For D+/D–:
V = 0V for t_PZH and t_PHZ
V = V_BUS for t_PZL and t_PLZ
Load for Enable and Disable Time (D+/D–)
Device
Under
Test
25pF
Result
SE0
Logic 0
Logic 1
Undefined
Result
SE0
Logic 0
Logic 1
Undefined
Micrel
MIC2550
V_P, V_M, and RCV Load
Device
Under
Test
V_TRM
1.5kΩ*
24Ω
15kΩ C_L
C_L = 50pF, full speed
C_L = 50pF, low speed (minimum timing)
C_L = 600pF, low speed (maximum timing)
*1.5k on D– for low speed or D+ for high speed
D+ and D– Load
6
October 4, 1999