IFX 80471SK V50 Infineon Technologies, IFX 80471SK V50 Datasheet - Page 21

• Manufacturer Part Number: IFX 80471SK V50
• Manufacturer: Infineon Technologies

Specifications of IFX 80471SK V50

• Packages: PG-DSO-14
• Comment: Vin up to 60V; external MOS; PG-DSO-14
• Vq (max): 5.0 V
• Iq (max): 2,300.0 mA
• Iq (typ): 130.0 µA
• Output: Buck Converter

6.2
To detect undervoltage conditions at the battery a sense comparator block is available within the IFX80471. The
voltage at the SI input is compared to an internal reference of typ. 1.25V. The output of the comparator drives a
NMOS structure giving a low signal at SO as soon as the voltage at SI decreases below this threshold. In the 5V
fixed version an internal pull up resistor is connected from the drain of the NMOS to the output of the buck
converter, in the variable version SO is open drain.
The sense in voltage divider can be switched to high impedance by a low signal at the SI_ENABLE to avoid high
current consumption to GND (IFX80471SKV50 only).
Of course the sense comparator can be used for any input voltage and does not have to be used for the battery
voltage sense only.
6.3
The output voltage is monitored continuously by the internal undervoltage reset comparator. As soon as the output
voltage decreases below the thresholds given in the characteristics the NPN structure pulls RO low (latched). In
the 5V fixed version an internal pull up resistor is connected from the collector of the NPN to the output of the buck
converter, in the variable version RO is open collector.
At power up RO is kept low until the output voltage has reached its reset threshold and stayed above this threshold
for the power on reset delay time.
Data Sheet
Battery voltage sense
Undervoltage Reset
20
Detailed Circuit Description
Rev. 1.0, 2011-02-07
IFX80471