Datasheet

MAX3453E–MAX3456E
±15kV ESD-Protected USB Transceivers
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Detailed Description
The MAX3453E–MAX3456E USB-compliant transceivers
convert single-ended or differential logic-level signals to
USB signals, and USB signals to single-ended or differ-
ential logic-level signals. The MAX3453E fully complies
with full-speed (12Mbps) operation under USB specifica-
tion 2.0. The MAX3454E–MAX3456E fully comply with
USB specification 1.1, and full-speed (12Mbps) and low-
speed (1.5Mbps) operation under USB specification 2.0.
The MAX3453E–MAX3456E operate with V
L
as low as
+1.65V, ensuring compatibility with low-voltage ASICs.
The MAX3453E–MAX3456E derive power from the USB
host (V
BUS
) or from a single-cell Li+ battery
(MAX3454E/MAX3456E) connected to V
BUS
or from a
+3.3V regulated supply connected to V
BUS
and V
TRM
.
The MAX3453E–MAX3456E meet the physical layer
specifications for logic-level supply voltages (V
L
) from
+1.65V to +3.6V. Integrated ±15kV ESD protection safe-
guards the D+ and D- USB I/O ports.
The MAX3453E/MAX3454E feature an enumerate func-
tion providing an internal 1.5kΩ pullup resistor from D+
(MAX3453E/MAX3454E) or D- (MAX3454E only) to
V
TRM
. The enumerate function disconnects the 1.5kΩ
pullup resistor, allowing the MAX3453E/MAX3454E to
simulate a bus disconnect while powered and connect-
ed to the USB cable. The MAX3453E/MAX3455E fea-
ture a bus-detect output (BD) that asserts high if V
BUS
> +4V. BD asserts low if V
BUS
< +3.6V. The
MAX3455E/MAX3456E require external pullup resistors
from either D+ or D- to V
TRM
to utilize the appropriate
bus speed. The MAX3456E is pin-for-pin compatible
with the Micrel MIC2550A.
Applications Information
Power-Supply Configurations
Normal Operating Mode
Connect V
L
and V
BUS
to system power supplies (Table 1).
Connect V
L
to a +1.65V to +3.6V supply. Connect V
BUS
to a +4.0V to +5.5V supply. Alternatively, the MAX3454E/
MAX3456E can derive power from a single Li+ battery.
Connect the battery to V
BUS
.
Additionally, the MAX3454E/MAX3456E can derive
power from a +3.3V ±10% voltage regulator. Connect
V
BUS
and V
TRM
to an external +3.3V voltage regulator.
V
BUS
no longer consumes current to power the internal
linear regulator in this configuration.
Table 1. Power-Supply Configurations
V
BUS
(V) V
TRM
(V) V
L
(V) CONFIGURATION NOTES
4.0 to 5.5 3.0 to 3.6 output 1.65 to 3.6 Normal mode —
3.1 to 4.5 3.0 to 3.6 output 1.65 to 3.6 Battery supply
MAX3454E/MAX3456E
3.0 to 3.6 3.0 to 3.6 input 1.65 to 3.6
Voltage regulator supply
MAX3454E/MAX3456E
GND or floating High-Z 1.65 to 3.6 Sharing mode Table 2
3.0 to 5.5 High-Z GND or floating Disable mode Table 2
*High impedance or low.
**High or low.
INPUTS/OUTPUTS DISABLE MODE SHARING MODE
V
BUS
/V
TRM
+3.0V to +5.5V / High Impedance
• Floating or connected to GND
(MAX3453E/MAX3454E/MAX3456E) / High Impedance
• < 3.6V (MAX3453E/MAX3455E) / High Impedance
V
L
Floating or connected to GND 1.65V to 3.6V input
D+ and D- High impedance High impedance
High impedance for OE = low
VP and VM Invalid*
High for OE = high
RCV Invalid* Undefined**
SPD (MAX3454E–MAX3456E),
SUS, OE, ENUM
(MAX3453E/MAX3454E)
High impedance High impedance
BD (MAX3453E/MAX3455E)
Invalid* Low
Table 2. Disable-Mode and Sharing-Mode Connections