Data Sheet 15 Rev. 1.2, 2009-11-09
TLE4253
Electrical Characteristics
5.3 Adjust / Enable Input
In order to reduce the quiescent current to a minimum, the TLE4253 can be switched to stand-by mode by setting
the adjust/enable input “ADJ/EN” to “low”.
In case the pin “ADJ/EN is left open, an internal pull-down resistor keeps the voltage at the pin low and therefore
ensures that the regulator is switched off.
Typical Performance Characteristics Tracking Regulator
V
ADJ/EN
= 5 V; V
FB
= V
Q
(unless otherwise noted)
Table 3 Electrical Characteristics Adjust / Enable
V
I
= 13.5 V; V
ADJ/EN
≥ 2.0 V; V
FB
= V
Q
; -40 °C ≤ T
j
≤ 150 °C;
all voltages with respect to ground (unless otherwise specified).
Pos. Parameter Symbol Limit Values Unit Test Condition
Min. Typ. Max.
5.3.1 Adjust / Enable
Low Signal Valid
V
ADJ/EN,low
––0.4VV
Q
= 0 V;
I
I
< 2 µA;
T
j
≤ 85 °C
5.3.2 Adjust / Enable
High Signal Valid
(Tracking Region)
V
ADJ/EN,high
2––VV
Q
settled:
|
V
Q
- V
ADJ/EN
| < 10 mV;
I
Q
= 10 mA
5.3.3 Adjust / Enable
Input Current
I
ADJ/EN
–3.85.5µAV
ADJ/EN
= 5 V;
5.3.4 Adjust / Enable
internal pull-down resistor
R
ADJ/EN
11.52MΩ
Startup Sequence
0
t
[µs]
20 60 80 120 140
V
[V]
4253_startup.vsd
3
2
1
4
40 100
V
ADJ
d
V
Q
/ d
t
=
(
I
Q,max
-
I
Load
) /
C
Q
Overshoot depends on
load current, C
Q
, ESR (C
Q
)
