Quad-channel, 2/2, 25-Mbps digital isolator

The ISO7240x,

ISO7241x, and ISO7242x devices

are quad-channel digital isolators with multiple channel configurations and

output-enable functions. These devices have logic-input and logic-output buffers

separated by Texas Instrument’s silicon-dioxide (SiO2) isolation barrier.

Used in conjunction with isolated power supplies, these devices help block high

voltage, isolate grounds, and prevent noise currents from entering the local ground

and interfering with or damaging sensitive circuitry.

The

ISO7240x family of devices has all four channels in the same direction. The ISO7241x

family of devices has three channels in the same direction and one channel in the

opposition direction. The ISO7242x family of devices has two channels in each

direction.

The devices with the C suffix (C

option) have TTL input thresholds and a noise-filter at the input that prevents

transient pulses from being passed to the output of the device. The devices with the

M suffix (M option) have CMOS VCC/2 input thresholds and do not have the

input noise filter or the additional propagation delay.

The ISO7240CF

device has an input

disable function on pin 7, and a selectable high or low failsafe-output function

with the CTRL pin (pin 10). The failsafe output is a logic high when a logic high is

placed on the CTRL pin or the pin is left unconnected. If a logic low signal is

applied to the CTRL pin, the failsafe output becomes a logic-low output state. The

input disable function of the ISO7240CF

device prevents data

from being passed across the isolation barrier to the output. When the inputs are

disabled or VCC1 is powered down, the outputs are set by the CTRL

pin.

These devices can be powered from 3.3V

or 5V supplies on either side, in any combination. The signal input pins are 5V

tolerant regardless of the voltage supply level that is used.

These devices are characterized for

operation over the ambient temperature range of –40°C to +125°C.