MIC2551AYTS Micrel Inc, MIC2551AYTS Datasheet - Page 8

• Manufacturer Part Number: MIC2551AYTS
• Description: IC USB TRANSCEIVER 14-TSSOP
• Manufacturer: Micrel Inc
• Type: USB Transceiverr

Specifications of MIC2551AYTS

• Number Of Drivers/receivers: 1/1
• Protocol: USB 2.0
• Voltage - Supply: 4 V ~ 5.25 V
• Mounting Type: Surface Mount
• Package / Case: 14-TSSOP
• Number Of Transceivers: 1
• Esd Protection: YeskV
• Operating Supply Voltage (typ): Not RequiredV
• Package Type: TSSOP
• Operating Temperature Classification: Industrial
• Operating Supply Voltage (max): Not RequiredV
• Operating Supply Voltage (min): Not RequiredV
• Dual Supply Voltage (typ): 1.8/2.5/3.3/5V
• Pin Count: 14
• Mounting: Surface Mount
• Operating Temperature (max): 85C
• Operating Temperature (min): -40C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 576-2182; MIC2551AYTS

MIC2551A
Power Supply Configuration
The MIC2551A can be set up for different power supply
configurations which modify the behavior of the device. Both
V
are either removed or grounded. Table 3 depicts the behavior
under the different power supply configuration scenarios that
are explained below.
Normal Mode
V
connected to a supply voltage in the range of 1.6V to 3.6V. In
this case V
speed select resistor via V
pin.
Disconnect Mode
V
V
ting, the data lines (D+, D–) have sharing capability and may
be driven with external devices up to approximately 3.6V if
and only if SUSPEND is enabled (SUS = 1). With V
ground, D+, D– sharing mode is not permitted.
Disable Mode
V
open. All logic controlled inputs become high impedances,
thus minimal current will be supplied by V
pulled up to an external source.
Alternate Power Supply Configuration Options
I/O Interface Using 3.3V
In systems where the I/O interface utilizes a 3.3V USB
controller, an alternate solution is shown in Figure 7. No extra
components are required; however, the load on V
not exceed 10mA.
Signal Amplitude Respective to V
When operating the MIC2551A, it is necessary to provide
input signals which do not exceed V
M9999-112008
Configuration Mode
Normal
Disconnect
(D+/D– sharing)
Disconnect
Disable Mode
Prohibited
BUS
BUS
IF
BUS
BUS
is connected to a supply in a range of 1.6V to 3.6V and
is open or grounded. If V
and V
is connected to the 5.0V USB bus voltage and V
is connected to the 5.0V USB bus voltage and V
3.3V
Controller
IF
Figure 7. I/O Interface Using 3.3V
TRM
V
USB
have special thresholds that detect when they
DD
supplies a 3.3V voltage for powering the
I/O
PU
VBUS/VTRM
VIF
V
RCV/OE#
depending on the state of CON
Connected
Connected
Connected
P
/V
BUS
Ground
MIC2551
M
Open
/
is opened while transmit-
IF
IF
VTRM
VBUS
+ 0.3V.
IF
if the input pins are
Table 3. Power Supply Configuration
Connected
Connected
Connected
Ground
VBUS
Open
VIF
TRM
must
IF
IF
BUS
is
is
8
Normal supply configuration and operation.
VP/VM are HIGH outputs, RCV is LOW.
With OE# = 0 and SUS = 1, data lines may be driven with
external devices up to 3.6V.
With D+, D– floating, I
VP/VM are HIGH outputs, RCV is LOW.
With D+, D– floating, I
Logic controlled inputs pins are Hi-Z.
Prohibited condition.
Suspend
When the suspend pin (SUS) is high, power consumption is
reduced to a minimum. V
are still functional to enable the device to detect USB activity.
For minimal current consumption in suspend mode, it is
recommended that OE# = 1, and SPD = 0.
Speed
The speed pin (SPD) sets D+/D– output edge rates by increas-
ing or decreasing biasing current sources within the output
drivers. For low speed, SPD = 0. For full speed, SPD = 1. By
setting SPD = 0 during idle periods, in conjunction with suspend
(SUS), the lowest quiescent current can be obtained. However,
designers must provide a 300ns delay between changing SPD
from 0 to 1 and transmission of data at full speed. This delay
ensures the output drivers have arrived at their proper operating
conditions. Failure to do so can result in leading edge distortion
on the first few data bits transmitted.
External ESD Protection
The use of ESD transient protection devices is not required
for operation, but is recommended. We recommend the
following devices or the equivalent:
Cooper Electronic Technologies (www.cooperet.com)
Littelfuse (www.littelfuse.com)
Non-Multiplexed Bus
In order to save pin count for the USB logic controller
interface, the MIC2551A was designed with V
directional pins. To interface the MIC2551A with a non-
multiplexed data bus, resistors can be used for low cost
isolation as shown in Figure 8.
41206ESDA SurgX
0805ESDA SurgX
V0402MHS05
SP0503BAHT
Figure 8. MIC2551A Interface to
Non-Multiplexed Data Bus
USB Logic
Controller
IF
IF
(SIE)

draws less than 1µA.
draws less than 1µA.

V
V
V
V
MO
PO
TRM
M
P
Notes
is not disabled. RCV, V
10k
10k
V
V
P
M
MIC2551
November 2008
P
and V
Micrel, Inc.
P
and V
M
as bi-
M