### Cross Reference Search

About information presented in this cross reference

The information presented in this cross reference is based on TOSHIBA's selection criteria and should be treated as a suggestion only. Please carefully review the latest versions of all relevant information on the TOSHIBA products, including without limitation data sheets and validate all operating parameters of the TOSHIBA products to ensure that the suggested TOSHIBA products are truly compatible with your design and application.
Please note that this cross reference is based on TOSHIBA's estimate of compatibility with other manufacturers' products, based on other manufacturers' published data, at the time the data was collected.
TOSHIBA is not responsible for any incorrect or incomplete information. Information is subject to change at any time without notice.

### Stock Check & Purchase

Select Product Categories

Select Application

Find everything you need for your next product design. Simply select an application and click through to the block diagram to discover our semiconductor solutions.

New Products / News

Design & Development

Knowledge

# What is the maximum operating frequency of level shifters?

• The maximum operating frequency of the bus buffer type can be calculated from the propagation delay times that are determined by the CR values of the load and on-resistance.
Maximum operating frequency ≈ 1/(tpLH ＋ tpHL)
• The maximum operating frequency of the bus switch type can be calculated based on the rise waveform.
Maximum operating frequency ≈ 1/(τ), where τ is a time constant:
Since τ is determined by charging and discharging time, τ is calculated from the time required for the output voltage to reaches 63%. (See the figure.)
1/τ = 1/(C×R)

Take, for example, the TC7SPB9306 with a switch I/O capacitance (CI/O) of 14 pF. Assume a load capacitance (CL) of 30 pF and a pullup resistor (Rpu) of 1 kΩ. Then, τ is calculated as follows:
τ = (14 pF + 30 pF) × 1 kΩ
Hence, the maximum operating frequency is calculated as roughly 20 MHz.

The result of this calculation should be considered merely as an estimate under the conditions shown in the datasheet.
Level shifters should be sufficiently evaluated to ensure that they work properly under the actual operating conditions because their propagation delay times change with the board capacitance and other conditions.

A new window will open
Site Map

Semiconductor Products

Storage Products

Other Products

Company