Datasheet

Data Sheet 8 Rev. 1.4, 2007-02-19
TLE 4278 G
Upper timing threshold V
DU
1.5 1.9 2.3 V –
Lower reset timing
threshold
V
DRL
0.2 0.3 0.4 V –
Delay time
t
rd
12 20 28 ms C
D
= 47 nF
Reset reaction time
t
rr
0.4 1.0 2.0 µs C
D
= 47 nF
Watchdog
Activating threshold
V
WADJ,th
1.28 1.35 1.45 V Voltage at WADJ
Current ratio
I
Q
/I
WADJ
650 720 800 – I
Q
≤ 10 mA
Slew rate d
V
WI
/dt 5––V/µs From 20% up to 80% V
Q
Watchdog low voltage V
WOL
–0.20.4VR
ext
> 10 kΩ to V
Q
Watchdog high voltage V
WOH
4.5––V–
Watchdog pull-up
R
WO
20 30 45 kΩ Internal connected to V
Q
Charge current I
D,wc
258µA V
D
= 1.0 V
Discharge current
I
D,wd
0.6 1.3 2.0 µA V
D
= 1.0 V
Upper timing threshold
V
DU
1.5 1.9 2.3 V –
Lower watchdog
timing threshold
V
DWL
0.5 0.7 0.9 V –
Watchdog output
pulse period
T
WD,p
42 60 80 ms C
d
= 47 nF
Watchdog output low
time
t
WD,l
71319msV
Q
> V
RT
Watchdog trigger time T
WI,tr
35 47 61 ms C
d
= 47 nF
1) Measured when the output voltage V
Q
has dropped 100 mV from the nominal value.
Table 4 Electrical Characteristics (cont’d)
V
I
= 13.5 V; -40 °C ≤ T
j
≤ 125 °C (unless otherwise specified)
Parameter Symbol Limit Values Unit Test Condition
Min. Typ. Max.