Application information

LNBH221

10/27

Moreover, it is possible to set the Short Circuit Current protection either statically (simple

Limiting) bit is set to LOW, the overcurrent protection circuit works dynamically, as soon as

Simultaneously the OLF bit of the System Register is set to HIGH. After this time has

timer. This dynamic operation can greatly reduce the power dissipation in short circuit

condition, still ensuring excellent power-on start up in most conditions. However, there could

be some cases in which an highly capacitive load on the output may cause a difficult start-

up when the dynamic protection is chosen. This can be solved by initiating any power start-

up in static mode (PCL=HIGH) and then switching to the dynamic mode (PCL=LOW) after a

chosen amount of time. When in static mode, the OLF bit goes HIGH when the current

clamp limit is reached and returns LOW when the overload condition is cleared. This IC is

also protected against overheating: when the junction temperature exceeds 150°C (typ.),

the step-up converter and the linear regulator are shut off, and the OTF SR bit is set to

HIGH. Normal operation is resumed and the OTF bit is reset to LOW when the junction is

cooled down to 140°C (typ.).

Note:

implied by the use of this IC.

Note:

Semiconductors.

5.1

Data transmission from main µP to the LNBH221 and viceversa takes place through the 2

positive supply voltage must be externally connected).

5.2

Data validity

As shown in Figure 5., the data on the SDA line must be stable during the high period of the

clock. The HIGH and LOW state of the data line can only change when the clock signal on

the SCL line is LOW.

5.3

Start and stop conditions

As shown in Figure 6. a start condition is a HIGH to LOW transition of the SDA line while

SCL is HIGH.

The stop condition is a LOW to HIGH transition of the SDA line while SCL is HIGH. A STOP

conditions must be sent before each START condition.