TABLE 3. P-bit Truth Table

Operation

P-bit

Description

Read

1

Programming Ready

Read

0

Programming Busy

(don’t turn off the device)

Write

1

Register Write

Write

0

EEPROM Write

The LM8342 can be used in I

clock speeds of up to 400 kbps (Fast mode). For low speed

applications, an initial resistor value for the pull-up resistors

is 15 k

Ω is suitable. When increasing the speed of the

interface bus, the user should decrease the value of the

pull-up resistors.

Typical Application

The following section discusses two typical applications for

the LM8342. In the first application the LM8342 is used as a

programmable current sink, for example to drive a program-

mable bias generator. In the second application the LM8342

is used to adjust the voltage level of a V

PROGRAMMABLE CURRENT SINK

As described in the “Principle of Operation of the LM8342”

section the LM8342 basically operates as a programmable

current sink. Figure 7 shows a general current sink

application.

The output current of the LM8342 can be calculated using

Equation (3).

(3)

DRIVING A V

Another typical application, given in Figure 8, is using the

LM8342 to adjust the “voltage tap” of a resistive voltage

divider. The V

application.

20139233

FIGURE 7. Programmable Current Sink

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