Datasheet
4k
4k
A B
V
CCA
V
CCB
One
Shot
One
Shot
One
Shot
One
Shot
T1
T2
T3
T4
TXB0104
SCES650F –APRIL 2006–REVISED MAY 2012
www.ti.com
PRINCIPLES OF OPERATION
Applications
The TXB0104 can be used in level-translation applications for interfacing devices or systems operating at
different interface voltages with one another.
Architecture
The TXB0104 architecture (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 TXB0104 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 the opposite direction.
The output one shots detect 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. The typical output impedance during output transition is 70 Ω at V
CCO
= 1.2 V to 1.8 V,
50 Ω at V
CCO
= 1.8 V to 3.3 V, and 40 Ω at V
CCO
= 3.3 V to 5 V.
Figure 1. Architecture of TXB0104 I/O Cell
Input Driver Requirements
Typical I
IN
vs V
IN
characteristics of the TXB0104 are shown in Figure 2. For proper operation, the device driving
the data I/Os of the TXB0104 must have drive strength of at least ±2 mA.
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