Device description

RHFL4913XX15 - RHFLXX25 - RHFLXX33 - RHFLXX50

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Device description

The RHFL4913 fixed voltage contains a PNP type power element controlled by a signal

resulting from amplified comparison between the internal temperature compensated band-

gap cell and the fraction of the desired output voltage value. This fractional value is obtained

from an internal-to-die resistor divider bridge set by STMicroelectronics. The device is

protected by several functional blocks.

5.1

Low pin count package limitations

Some functions (INHIBIT, OCM, SENSE) are not available due to lack of pins.

Corresponding die pads are by default connected inside silicon.

5.2

SENSE pin

The load voltage is applied by a Kelvin line connected to SENSE pin: Voltage feed-back

comes from the internal divider resistor bridge. Therefore possible output voltages are set

by manufacturer mask metal options. SENSE pin is not available in 3pin packages.

5.3

Inhibit ON-OFF control

By setting INHIBIT pin TTL-high, the device switches off the output current and voltage. The

device is ON when INHIBIT pin is set low. Since INHIBIT pin is internally pulled down, it can

be left floating in case inhibit function is not utilized. INHIBIT pin is not available in 3pin

packages.

5.4

Overtemperature protection

A temperature detector internally monitors the power element junction temperature. The

device goes OFF at approx. 175 °C, returning to ON mode when back to approx. 40 °C. It is

worth noting that when the internal temperature detector reaches 175 °C, the active power

element can be at 225 °C: device reliability cannot be granted in case of extensive operation

under these conditions.

5.5

Overcurrent protection

with a typical value range of 10 k

Ω to 200 kΩ. This adjustment feature is not available in 3

packages).