8 Detailed Description

8.1 Overview

The SN74HCS367 contains 6 individual high speed CMOS buffers with Schmitt-trigger inputs and 3-state

outputs.

Each buffer performs the boolean logic function xYn = xAn, with x being the bank number and n being the

channel number.

The first bank includes four buffers, and the second bank includes two buffers.

Each output enable (xOE) controls one bank of buffers. When the xOE pin is in the low state, the outputs of all

buffers in the bank x are enabled. When the xOE pin is in the high state, the outputs of all buffers in the bank x

are disabled. All disabled output are placed into the high-impedance state.

To ensure the high-impedance state during power up or power down, both xOE pins should be tied to VCC

through a pull-up resistor. The value of the resistor is determined by the current sinking capability of the driver

and the leakage of the pin as defined in the Electrical Characteristics table. Typically a 10 kΩ resistor will be

sufficient.

8.2 Functional Block Diagram

1A2

1A3

1A4

1A1

1OE

1Y1

1Y2

1Y3

1Y4

2A2

2A1

2OE

2Y1

2Y2

Figure 8-1. Logic Diagram (Positive Logic) for SN74HCS367

8.3 Feature Description

8.3.1 Balanced CMOS 3-State Outputs

This device includes balanced CMOS 3-State outputs. The three states that these outputs can be in are driving

high, driving low, and high impedance. The term "balanced" indicates that the device can sink and source similar

currents. The drive capability of this device may create fast edges into light loads so routing and load conditions

should be considered to prevent ringing. Additionally, the outputs of this device are capable of driving larger

currents than the device can sustain without being damaged. It is important for the output power of the device to

be limited to avoid damage due to overcurrent. The electrical and thermal limits defined in the Absolute

Maximum Ratings must be followed at all times.

When placed into the high-impedance mode, the output will neither source nor sink current, with the exception of

minor leakage current as defined in the Electrical Characteristics table. In the high-impedance state, the output

voltage is not controlled by the device and is dependent on external factors. If no other drivers are connected to

the node, then this is known as a floating node and the voltage is unknown. A pull-up or pull-down resistor can

SN74HCS367

SCLS838 – OCTOBER 2020

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