| 摘要 |
An interface for use of device whose core circuitry operates in one voltage domain, but exchanges signal with another device (or “host”) according a different voltage domain, and the use of such an interface for supplying data using a double data rate (DDR) transfer, is presented. One concrete example of this situation is a memory card, where the internal circuitry uses one voltage range for its core operating voltages, but exchanges signals with a host using different, input/output voltage range. According to a general set of aspects, the interface receives data signals from the device at the device's core operating voltage domain, individually level shifts these to the input/output voltage domain, and then combines them into a DDR signal for transfer to the host device, where a (non-level shifted) clock signal from the host device is used as the select signal to form the DDR data signal. |
