Datasheet

731
32133D–11/2011
UC3D
Figure 32-6. Dual Supply Configuration
32.9.5 RESET_N Characteristics
32.10 USB Transceiver Characteristics
32.10.1 Electrical Characteristics
The USB on-chip buffers comply with the Universal Serial Bus (USB) v2.0 standard. All AC
parameters related to these buffers can be found within the USB 2.0 electrical specifications.
V
D
D
R
R
2
.
5
V
/
m
s
m
i
n
i
m
u
m
Vpor+ min
VDDIO min
<500us
VDDIO
VDDCORE
Internal
POR
(active low)
TRST
TSSU1
First instruction
fetched in flash
Table 32-30. RESET_N Waveform Parameters
Symbol Parameter Conditions Min. Typ. Max. Unit
t
RESET
RESET_N minimum pulse width 10 ns
Electrical Parameters
Symbol Parameter Conditions Min. Typ. Max. Unit
R
EXT
Recommended External USB Series
Resistor
In series with each USB pin with
±5%
39
Ω