UM3301 Datasheet, PDF (8/13 Pages) ShenZhen XinDeYi Electronics Co., Ltd. – N-Ch and P-Ch Fast Switching MOSFETs

UM3301
Applications Information
The UM3301B/UM3301DA ESD protected level translator provides level shifting necessary to
allow data transfer in a multi-voltage system. Externally applied voltages, V_CCA and V_CCB set the
logic levels on either side of device. A low voltage signal present on V_CCA side of the device
appears as a high voltage logic signal on the V_CCB side of the device, and vice-versa.
Block Diagram
The UM3301B/UM3301DA (block diagram see Figure 1) does not require a direction-control
signal to control the direction of data flow from A to B or from B to A. In a dc state, the output
drivers of the UM3301B/UM3301DA can maintain a high or low, but are designed to be weak, so
that they can be overdriven by an external driver when data on the bus starts flowing towards the
opposite direction.
The output one shot detects rising or falling edges on the A or B ports. During a rising edge, the
one shot turns on the PMOS transistors (T1, T3) for a short duration, which speeds up the
low-to-high transition. Similarly, during a falling edge, the one shot turns on the NMOS
transistors (T2, T4) for a short duration, which speeds up the high-to-low transition.
VCCA
VCCB
I/O A
P
One Shot
T3
4K
T4
N
One Shot
P
One Shot
T1
4K
N
One Shot
T2
I/O B
Figure 1 Block Diagram of UM3301B/UM3301DA I/O Cell
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