TLE7469_08 Datasheet, PDF (12/21 Pages) Infineon Technologies AG – Dual Low Drop Voltage Regulator Ultra low quiescent current consumption < 55 μA

Application Information
TLE 7469
V_Bat
47
µF
e. g.
Ignition
Key
R_Vi *
100 nF
100 kΩ
TLE 7469
I2
Q2
DT
INH
WDI
RO
SI
SO
100 nF
I1
Q1
GND
= Optional
1 µF
47
µF
XC 164
10 kΩ
1 µF
47
µF
AEA03529_2.VSD
Figure 3 Application Diagram with Typical External Components
A typical application of the TLE 7469 is shown in Figure 3. To prevent the regulation
loop from oscillating a ceramic capacitor of C_Q1/2 ≥ 1 µF is required at each of the outputs
Q1 and Q2. In contrast to most low drop voltage regulators the TLE 7469 only needs
moderate capacitance at the outputs and tolerates ceramic capacitors to keep the
stability. This offers more design flexibility to the circuit designer enabling the IC also to
operate without tantalum capacitors.
Additional a buffer capacitor C_B of > 10µF should be used for each output Q1 and Q2 to
suppress 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.
min. 130mV for the 2.6V Output).
Data Sheet
12
Rev. 1.6, 2008-01-22