FUNCTION
11 11 11 11 D+
USB Input/Output. For OE = GND, D+ functions as a USB
output, with VP providing the input signal. For OE = V
L
, D+
functions as a USB input, with VP functioning as a single-ended
receiver output. Connect a 1.5kΩ resistor from D+ to V
TRM
for
full-speed (12Mbps) operation (MAX3455E/MAX3456E). Drive
ENUM to V
L
to connect the internal 1.5kΩ resistor (MAX3453E/
MAX3454E) from D+ to V
TRM
for full-speed (MAX3454E, SPD =
V
L
) operation.
12 12 12 12 V
TRM
Internal Regulator Output. V
TRM
provides a regulated +3.3V
output. Bypass V
TRM
to GND with a 1µF (min) ceramic
capacitor as close to the device as possible. V
TRM
normally
derives power from V
BUS
. Alternatively, drive V
TRM
directly with
a +3.3V ±10% supply (MAX3454E/MAX3456E). V
TRM
provides
power to internal circuitry and provides the pullup voltage for an
external USB pullup resistor (MAX3455E/MAX3456E). Do not
use V
TRM
to power external circuitry.
13
(MAX3455E
only)
13
(MAX3455E
only)
13 13 BD
Bus-Detection Output (MAX3453E/MAX3455E). The push-pull
BD output asserts low and the device enters sharing mode if
V
BUS
< +3.6V. BD asserts high if V
BUS
> +4.0V.
13
(MAX3454E
only)
13
(MAX3454E
only)
21
Enumerate Function Selection Input (MAX3453E/MAX3454E).
Drive ENUM to V
L
to connect the internal 1.5kΩ resistor
between V
TRM
and D+ or D-, depending on the state of SPD.
Drive ENUM to GND to disconnect the internal 1.5kΩ resistor.
For SPD = V
L
, the 1.5kΩ resistor connects to D+. For SPD =
GND, the 1.5kΩ resistor connects to D-. For the MAX3453E, the
resistor only connects to D+.
14 14 14 14 V
BUS
USB Power-Supply Input. Connect a +4.0V to +5.5V power
supply to V
BUS
. V
BUS
provides power to the internal linear
regulator. Bypass V
BUS
to GND with a 0.1µF ceramic capacitor
as close to the device as possible. Connect V
BUS
and V
TRM
together when powering the MAX3454E/MAX3456E with an
external power supply (+3.3V ±10%).
