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MIC2550A Datasheet, PDF (6/11 Pages) Micrel Semiconductor – Universal Serial Bus Transceiver
MIC2550A
Micrel, Inc.
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
Note. X = undefined.
Test Circuits
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
Device
Under
Test
Test
Point
24Ω
500Ω
50pF
V
For D+, D–:
V = 0V for tPZH and tPHZ
V = VBUS for tPZL and tPLZ
Figure 5. Load for Enable and Disable Time (D+, D–)
Result
SE0
Logic 0
Logic 1
Undefined
Result
SE0
Logic 0
Logic 1
Undefined
Device
Under
Test
25pF
M9999-031805
Figure 6. VP, VM and RCV Load
Device
Under
Test
VTRM
1.5kΩ*
24Ω
15kΩ CL
CL = 50pF, full speed
CL = 50pF, low speed (minimum timing)
CL = 600pF, low speed (maximum timing)
*1.5k on D– for low speed or D+ for high speed
Figure 7. D+ and D– Load
6
March 2005