TLE 7272G Infineon Technologies, TLE 7272G Datasheet - Page 9

• Manufacturer Part Number: TLE 7272G
• Manufacturer: Infineon Technologies

Specifications of TLE 7272G

• Packages: P-TO263-5
• Regulator Type: single output
• Output Voltage: 5V
• Accuracy: 2.0 %
• Max. Output Current: 300mA
• Dropout Voltage: 250mV

Additionally a buffer capacitor C
influences from load surges to the voltage levels. This one can either be an aluminum
electrolytic capacitor or a tantalum capacitor following the application requirements.
A general recommendation is to keep the drop over the equivalent serial resistor (ESR)
together with the discharge of the blocking capacitor below the Reset Headroom (e.g.
typ. V
Since the regulator output current roughly rises linearly with time the discharge of the
capacitor can be calculated as follows:
The drop across the ESR calculates as:
To prevent a reset the following relationship must be fullfilled:
Example: Assuming a load current change of dI
22µF and a typical regulator reaction time under normal operating conditions of dt ~
25µs and for special dynamic load conditions, such as load step from very low base
load, a reaction time of dt ~ 75µs.
So for the ESR we can allow
The permissible ESR becomes:
During design-in of the TLE7469 product family, special care needs to be taken with
regards to the regulators reaction time to sudden load current changes starting from very
low pre-load as well as cyclic load changes. The application note “ TLE7x Voltage
Regulators - Application Note about Transient Response at ultra low quiescent current
Voltage Regulators ” (see 3_cip05405.pdf) gives important hints for successful design-in
of the Voltage Regulators of the TLE7x family.
Data Sheet
RH
= 350mV).
dVC
dV
dV
dV
dV
ESR = dV
ESR
C
C
ESR
B
+ dV
= dI
= dI
= dI*ESR
= V
Q
ESR
*dt/C
Q
RH2
ESR
*dt/C
< V
- dV
/ dI
B
= 100mA * 25µs/22µF = 113mV
B
RH
Q
C
= 236mV/100mA = 2.36Ohm
= 350mV
= 350mV - 113mV = 236mV
B
of > 10µF should be used for the output to suppress
9
Q
= 100mA, a blocking capacitor of C
Rev. 1.1, 2005-07-30
TLE 7272
B
=