DIO7S108

Version 1.4, Dec 2025

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© 2025 Dioo Microcircuits Co., Ltd. Jiangsu

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10.2. Power up and power down sequence

The DIO7S108 has an output enable pin which control the output status. When the OE input is low, all I/Os are

placed in the high-impedance state. To ensure the high-impedance state during power up or power down, OE

should be connected to GND via a pull-down resistor. Pins of A port and OE are referenced to VCCA and pins of B

port are referenced to VCCB.

Figure 7. Power up and power down sequence, tup / tdown ≥ 100 μs

10.3. Enable and disable

The DIO7S108 device has an OE input that disables the device by setting OE low, which places all I/Os in the

high-impedance (Hi-Z) state. The disable time (tdis) represents the delay between OE going low and the outputs

getting disabled (Hi-Z). The enable time (ten) represents the amount of time that the user must allow a one-shot

circuit to operate after EN is high.

10.4. Pullup or pulldown resistors on I/O lines

Every I/O on the A-port features an integrated 10 kΩ pull-up resistor connected to VCCA, while every I/O on the

B-port features an integrated 10 kΩ pull-up resistor connected to VCCB. When a lower resistance pull-up

resistor is necessary, add an external resistor from the I/O to either VCCA or VCCB, in parallel with the existing

internal 10 kΩ resistors.

10.5. Device functional modes

There are two functional modes for the device: enabled and disabled. The device can be enabled by setting the

OE input high. To disable the device, set the OE input low, which places all I/Os in a high impedance state.