The SN74AXCH8T245 device is an 8-bit non-inverting bus transceiver that resolves voltage
level mismatch between devices operating at the latest voltage nodes (0.7 V, 0.8 V, and 0.9 V) and
devices operating at industry standard voltage nodes (1.8 V, 2.5 V, 3.3 V) and vice versa.
The device operates by using two independent power-supply rails
(VCCA and VCCB) . Data pins A1 through A8 are designed to track VCCA,
which accepts any supply voltage from 0.65 V to 3.6 V. Data pins B1 through B8 are designed to
track VCCB, which accepts any supply voltage from 0.65 V to 3.6 V.
Additionally the SN74AXCH8T245 is compatible with a single-supply system.
The SN74AXCH8T245 device is designed for asynchronous communication between data buses.
The device transmits data from the A bus to the B bus or from the B bus to the A bus, depending on
the logic level of the direction-control inputs (DIR1 and DIR2). The output-enable
(OE) input is used to disable the outputs so the buses are effectively
isolated.
The SN74AXCH8T245 device is designed so the control pins (DIR and
OE) are referenced to VCCA.
Active bus-hold circuitry holds unused or undriven inputs at a valid logic state. Use of
pull-up or pull-down resistors with the bus-hold circuitry is not recommended. If a supply is
present for VCCA or VCCB, the bus-hold circuitry
always remains active on all A and B ports respectively, independent of the direction control or
output enable.
This device is fully specified for partial-power-down applications using
Ioff. The Ioff circuitry disables the outputs when
the device is powered down. This inhibits current backflow into the device which prevents damage to
the device.
The VCC isolation feature ensures that if either
VCC input supply is below 100 mV, all level shifter outputs are disabled and
placed into a high-impedance state. To ensure the high-impedance state of the level shifter I/Os
during power up or power down, OE should be tied to
VCCA through a pull-up resistor; the minimum value of the resistor is
determined by the current-sinking capability of the driver.
The SN74AXCH8T245 device is an 8-bit non-inverting bus transceiver that resolves voltage
level mismatch between devices operating at the latest voltage nodes (0.7 V, 0.8 V, and 0.9 V) and
devices operating at industry standard voltage nodes (1.8 V, 2.5 V, 3.3 V) and vice versa.
The device operates by using two independent power-supply rails
(VCCA and VCCB) . Data pins A1 through A8 are designed to track VCCA,
which accepts any supply voltage from 0.65 V to 3.6 V. Data pins B1 through B8 are designed to
track VCCB, which accepts any supply voltage from 0.65 V to 3.6 V.
Additionally the SN74AXCH8T245 is compatible with a single-supply system.
The SN74AXCH8T245 device is designed for asynchronous communication between data buses.
The device transmits data from the A bus to the B bus or from the B bus to the A bus, depending on
the logic level of the direction-control inputs (DIR1 and DIR2). The output-enable
(OE) input is used to disable the outputs so the buses are effectively
isolated.
The SN74AXCH8T245 device is designed so the control pins (DIR and
OE) are referenced to VCCA.
Active bus-hold circuitry holds unused or undriven inputs at a valid logic state. Use of
pull-up or pull-down resistors with the bus-hold circuitry is not recommended. If a supply is
present for VCCA or VCCB, the bus-hold circuitry
always remains active on all A and B ports respectively, independent of the direction control or
output enable.
This device is fully specified for partial-power-down applications using
Ioff. The Ioff circuitry disables the outputs when
the device is powered down. This inhibits current backflow into the device which prevents damage to
the device.
The VCC isolation feature ensures that if either
VCC input supply is below 100 mV, all level shifter outputs are disabled and
placed into a high-impedance state. To ensure the high-impedance state of the level shifter I/Os
during power up or power down, OE should be tied to
VCCA through a pull-up resistor; the minimum value of the resistor is
determined by the current-sinking capability of the driver.