Type Package
TLE 4278 G PG-DSO-14-30 (RoHS compliant)
5-V Low Drop Fixed Voltage Regulator
TLE 4278 G
P-DSO-14-3, -8, -9, -11, 14
PG-DSO-14-30
Data Sheet 1 Rev. 1.4, 2007-02-19
Features
• Output voltage tolerance ≤ ±2%
• Very low current consumption
• Separated reset and watchdog output
• Low-drop voltage
• Watchdog
• Adjustable watchdog activating threshold
• Adjustable reset threshold
• Overtemperature protection
• Reverse polarity protection
• Short-circuit proof
• Suitable for use in automotive electronics
• Wide temperature range
•
AEC qualified
• Green Product (RoHS compliant) version of TLE 4278 G
Functional Description
The TLE 4278 is a monolithic integrated low-drop fixed output voltage regulator
supplying loads up to 200 mA. The IC is available in a PG-DSO-14-30 package. It is
designed to supply microprocessor systems under the severe conditions of automotive
applications and therefore equipped with additional protection functions against over-
load, short circuit and overtemperature. The TLE 4278 can also be used in other
applications where a stabilized voltage is required.
An input voltage VI in the range of 5.5 V ≤ VI ≤ 45 V is regulated to VQ,nom = 5 V with an
accuracy of ±2%.
The device operates in the wide temperature range of Tj = -40 to 150 °C.
Two additional features are implemented in the TLE 4278 a load dependent watchdog
function as well as a sophisticated reset function including power on reset, under voltage
reset, adjustable reset delay time and adjustable reset switching threshold.
Data Sheet 2 Rev. 1.4, 2007-02-19
TLE 4278 G
The watchdog function monitors the microcontroller, including time base failures. In case
of a missing rising edge within a certain pulse repetition time the watchdog output is set
to LOW. Programming of the max. repetition time can be done easily by an external reset
delay capacitor. To prevent a reset in case of missing pulses, the watchdog output WO
is separate from the reset output RO for the TLE 4278. The watchdog output can be
used as an interrupt signal for the microcontroller. In any case it is possible to connect
pin WO and pin RO externally.
When the controller is set to sleep mode or low power mode its current consumption
drops and no watchdog pulses are created. In order to avoid unnecessary wake-up
signals due to missing pulses at pin WI the watchdog feature can be disabled as a
function of the load current. The switch off threshold is set by an external resistor to pin
WADJ. The watchdog function can also be used as a timer, which periodically wakes up
the controller. Therefore the pin WADJ has to be connected to the output Q.
The power on reset feature is necessary for a defined start of the microprocessor when
switching on the application. The reset signal at pin RO goes high after a certain delay
timed trd when the output voltage of the regulator has surpassed the reset threshold. The
delay time is set by the external delay capacitor. An under voltage reset circuit
supervises the output voltage. In case VQ falls below the reset threshold the reset output
is set to LOW after a short reset reaction time trr. The reset LOW signal is generated
down to an output voltage VQ of 1 V. In addition the reset switching threshold can be
adjusted by an external voltage divider. This feature is useful with microprocessors
which guarantee a safe operation down to voltages below the internally set reset
threshold of 4.65 V typical.
TLE 4278 G
Data Sheet 3 Rev. 1.4, 2007-02-19
Figure 1 Pin Configuration (top view)
Table 1 Pin Definitions and Functions
Pin Symbol Function
1WOWatchdog Output; the open collector output is connected to the
5 V output via an integrated resistor of 30 kΩ.
2WADJWatchdog Adjust; an external resistor to GND determines the
watchdog activating threshold.
3, 4, 5,
10, 11, 12
GND Ground
6DReset Delay; connect a capacitor to ground for delay time
adjustment.
7RADJReset Switching Threshold Adjust; for setting the switching
threshold, connect a voltage divider from output to ground. If this
input is connected to ground, the reset is triggered at the internal
threshold.
8WIWatchdog Input; rising edge-triggered input for monitoring a
microcontroller.
9Q5 V Output Voltage; block to ground with min. 10 µF capacitor,
ESR ≤ 5 Ω.
13 I Input Voltage; block to ground directly on the IC with ceramic
capacitor.
14 RO Reset Output; the open collector output is connected to the 5 V
output via an integrated resistor of 30 kΩ.
RO
GND
RADJ
D
GND
8W
12
11
GND
GND
1
2
3
4
5
GND
6
7
14
13
WO
WADJ
9
10
AEP02113
GND
V
V
Ι
Ι
Q
PG-DSO-14-30
Data Sheet 4 Rev. 1.4, 2007-02-19
TLE 4278 G
Figure 2 Block Diagram
AEB02114
Temperature
Sensor
-
+
Control
Amplifier
Protection
Circuit
Reference
Bandgap
Generator
Reset
Watchdog
W
14
9
7
6
V
RO
D
RADJ
13
Ι
3-5, 10-12
GND
8
2
WADJ
1WO
V
Ι
Q
TLE 4278 G
Data Sheet 5 Rev. 1.4, 2007-02-19
Table 2 Absolute Maximum Ratings
Tj = -40 to 150 °C
Parameter Symbol Limit Values Unit Notes
Min. Max.
Input Voltage I
Voltage VI-42 45 V –
Current II– – mA Internally limited
Output Voltage Q
Voltage VQ-1 25 V –
Current IQ– – mA Internally limited
Reset Output RO
Voltage VRO -0.3 25 V –
Current IRO -5 5 mA –
Reset Delay D
Voltage VD-0.3 7 V –
Current ID-2 2 mA –
Reset Switching Threshold Adjust RADJ
Voltage VRADJ -0.3 7 V –
Current IRADJ – – mA Internally limited
Watchdog Input WI
Voltage VWI -0.3 7 V –
Current IWI – – mA Internally limited
Watchdog Output WO
Voltage VWO -0.3 25 V –
Current IWO -5 5 mA –
Watchdog Adjust WADJ
Voltage VWADJ -0.3 7 V –
Current IWADJ – – mA Internally limited
Ground GND
Current IGND -100 50 mA –
Data Sheet 6 Rev. 1.4, 2007-02-19
TLE 4278 G
Note: ESD protection according to MIL Std. 883: ±2 kV.
Maximum ratings are absolute ratings; exceeding any one of these values may
cause irreversible damage to the integrated circuit.
Note: In the operating range the functions given in the circuit description are fulfilled.
Temperatures
Junction temperature Tj-50 150 °C–
Storage temperature Tstg -50 150 °C–
Table 3 Operating Range
Parameter Symbol Limit Values Unit Notes
Min. Max.
Input voltage VI5.5 45 V –
Junction temperature Tj-40 150 °C–
Thermal Resistance
Junction ambient Rthj-a –80K/W
1)
1) Package mounted on PCB 80 × 80 × 1.5 mm3; 35µ Cu; 5µ Sn; Heat Sink Area 6 cm2; zero airflow.
Junction pin Rthj-pin – 30 K/W Measured to pin 4
Table 2 Absolute Maximum Ratings (cont’d)
Tj = -40 to 150 °C
Parameter Symbol Limit Values Unit Notes
Min. Max.
TLE 4278 G
Data Sheet 7 Rev. 1.4, 2007-02-19
Table 4 Electrical Characteristics
VI = 13.5 V; -40 °C ≤ Tj ≤ 125 °C (unless otherwise specified)
Parameter Symbol Limit Values Unit Test Condition
Min. Typ. Max.
Output voltage VQ4.90 5.00 5.10 V 0 mA ≤ IQ ≤ 150 mA;
6 V ≤ VI ≤ 28 V
Output voltage VQ4.8 5.0 5.2 V 1 mA ≤ IQ ≤ 50 mA;
28 V ≤ VI ≤ 45 V
Output current limiting IQ200 400 – mA VQ = 4.8 V
Current consumption
Iq = II - IQ
Iq,o – 180 200 µATj = 25 °C;
IQ = 0 mA
Current consumption
Iq = II - IQ
Iq,o – 210 230 µAIQ = 0 mA;
Tj = 85 °C
Current consumption
Iq = II - IQ
Iq,150 –512mAIQ = 150 mA
Drop voltage
VDR = VI - VQ
Vdr –0.250.5VIQ = 150 mA1)
Load regulation ∆VQ.lo -30 -5 – mV IQ = 5 to 150 mA;
VI = 6 V
Line regulation ∆VQ,li –520mVVI = 6 to 28 V
IQ = 5 mA
Reset Generator
Reset threshold VQ,rt 4.5 4.65 4.8 V RADJ connected to GND
Reset headroom ∆VQ,rt =
(VQ,nom -
VQ,rt)
180 350 – mV IQ = 10 mA
Reset adjust threshold VRADJ,th 1.28 1.35 1.45 V VQ ≥ 3.5 V
Reset low voltage VRO,l –0.200.40VRext = 10 kΩ to VQ
VQ ≥ 1 V
Reset high voltage VRO,h 4.5––V–
Reset pull-up RRO 20 30 45 kΩInternal connected to VQ
Charging current ID,c 258µAVD = 1.0 V
Data Sheet 8 Rev. 1.4, 2007-02-19
TLE 4278 G
Upper timing threshold VDU 1.5 1.9 2.3 V –
Lower reset timing
threshold
VDRL 0.2 0.3 0.4 V –
Delay time trd 12 20 28 ms CD = 47 nF
Reset reaction time trr 0.4 1.0 2.0 µsCD = 47 nF
Watchdog
Activating threshold VWADJ,th 1.28 1.35 1.45 V Voltage at WADJ
Current ratio IQ/IWADJ 650 720 800 – IQ ≤ 10 mA
Slew rate dVWI/dt5––V/µs From 20% up to 80% VQ
Watchdog low voltage VWOL –0.20.4VRext > 10 kΩ to VQ
Watchdog high voltage VWOH 4.5––V–
Watchdog pull-up RWO 20 30 45 kΩInternal connected to VQ
Charge current ID,wc 258µAVD = 1.0 V
Discharge current ID,wd 0.6 1.3 2.0 µAVD = 1.0 V
Upper timing threshold VDU 1.5 1.9 2.3 V –
Lower watchdog
timing threshold
VDWL 0.5 0.7 0.9 V –
Watchdog output
pulse period
TWD,p 42 60 80 ms Cd = 47 nF
Watchdog output low
time
tWD,l 71319msVQ > VRT
Watchdog trigger time TWI,tr 35 47 61 ms Cd = 47 nF
1) Measured when the output voltage VQ has dropped 100 mV from the nominal value.
Table 4 Electrical Characteristics (cont’d)
VI = 13.5 V; -40 °C ≤ Tj ≤ 125 °C (unless otherwise specified)
Parameter Symbol Limit Values Unit Test Condition
Min. Typ. Max.
TLE 4278 G
Data Sheet 9 Rev. 1.4, 2007-02-19
Figure 3 Test Circuit
AES02115
TLE 4278
1000 FµnF
V
Ι
RO
Q
V
Ι
Ι
Ι
GND
Ι
Q
CD
47 nF
V
D
Ι
RO
O
V-
Ι
VV
DR=
470
RE
VV
W
V
Outside the control range
V
RO
G
Ι
WADJ
WO
VWADJ
WO
VRADJGND
13 9
6710-12
3-5,
D
1
2
814
WO
Ι
Ι
WADJ
QΙ
V
W
C
Ι12Ι
CC
Q
10 Fµ
Data Sheet 10 Rev. 1.4, 2007-02-19
TLE 4278 G
Application Information
Input, Output
The input capacitors CI1 and CI2 are necessary for compensating line influences. Using
a resistor of approx. 1 Ω in series with CI1, the LC circuit of input inductance and input
capacitance can be damped. To stabilize the regulation circuit the output capacitor CQ is
necessary. Stability is guaranteed at values CQ ≥ 10 µF with an ESR ≤ 5 Ω within the
operating temperature range.
Figure 4 Application Circuit
AES02116
TLE 4278G
C
D
47 nF
22 F
or short to GND
RADJ
WADJGND
13 9
6210-12
3-5,
D
7
µ
+12 V
Cooling
Area
8W
14 RO
WADJ
R R
2
1
R
*)
*)
Q
C
for internal threshold
P
1WO
Ι
V
Ι
V
Q
µ
470 nFC
Ι1
C
Ι2
TLE 4278 G
Data Sheet 11 Rev. 1.4, 2007-02-19
Reset Timing
The power-on reset delay time is defined by the charging time of an external capacitor
CD which can be calculated as follows:
CD = (∆trd × ID,c)/∆V(1)
Definitions:
•CD = delay capacitor
•∆trd = delay time
•ID,c = charge current, typical 5 µA
•∆V = VDU, typical 1.9 V
•VDU = upper delay switching threshold at CD for reset delay time
The reset reaction time trr is the time it takes the voltage regulator to set the reset out
LOW after the output voltage has dropped below the reset threshold. It is typically 1 µs
for delay capacitor of 47 nF. For other values for CD the reaction time can be estimated
using Equation (2):
trr ≈ 20 s/F × CD(2)
Figure 5 Reset Timing (watchdog disabled)
AED03010
Thermal
trd
Power-on-Reset Voltage Dip Secondary Overload
at OutputSpike
VΙ
D,c
Ι
=
Vd
dt
VQ
Q, rt
V
trr
<
rr
t
at Input Undervoltage
Shutdown
CD
t
VRO
D
V
t
t
t
VDU
VDRL
Data Sheet 12 Rev. 1.4, 2007-02-19
TLE 4278 G
Reset Switching Threshold
The present default value is 4.65 V. When using the TLE 4278 the reset threshold can
be set to 3.5 V < VQ,rt < 4.6 V by connecting an external voltage divider to pin RADJ. The
calculation can be easily done since the reset adjust input current can be neglected. If
this feature is not needed, the pin has to be connected to GND.
VQ,rt = Vref × (1 + R1/R2)(3)
Definitions:
•VQ,rt = Reset threshold
•Vref = comparator reference voltage, typical 1.35 V
(Reset adjust input current ≈ 50 nA)
Figure 6
The reset output pin is internally connected to the 5 V output Q via a 30 kΩ pull-up
resistor. Down to an output voltage VQ of typical 1 V the reset LOW signal at pin RO is
generated.
For the timing of the reset feature please refer to Figure 5.
AES03071
Band-Gap-
Reference
RO
RADJ
Ι
GND
Q
Reference
Band-Gap-
>1
+
-
1.35 V 1.35 V
30 kΩ
R
1
2
R
TLE 4278 G
13 9
14
7
3 ... 5, 10 ... 12
TLE 4278 G
Data Sheet 13 Rev. 1.4, 2007-02-19
Watchdog Activating
The calculation of the external resistor which adjusts the watchdog switch off threshold
can be done by Equation (4):
RWADJ = VWADJ,th × (IQ/IWADJ)/IQ,act (4)
Definitions:
•VWADJ,th = switch off threshold, typical 1.35 V
•IQ/IWADJ = current ratio, typical 720
•IQ,act = switch off load current
Figure 7
AES03072
Band-Gap-
Reference
GND
+
-
TLE 4278 G
Watchdog
active
HIGH
disabled
Watchdog
LOW
WADJ
R
WADJ
ΙQ
Data Sheet 14 Rev. 1.4, 2007-02-19
TLE 4278 G
Watchdog Timing
The frequency of the watchdog pulses has to be higher than the minimum pulse
sequence which is set by the external reset delay capacitor CD. Calculation can be done
according to the formulas given in Figure 8.
The watchdog output is internally connected to the output Q via a 30 kΩ pull-up resistor.
To generate a watchdog created reset signal for the microcontroller the pin WO can be
connected to the reset input of the microcontroller. It is also allowed to parallel the
watchdog out to the reset out.
Figure 8 Timing of the Watchdog Function
AED03099
W
V
V
VQ
D
V
VWO
VDU -VDWL
()
Ι
(D, wc+D, wd)
Ι
Ι
D, wc
Ι
xD, wd
TWD, p =
WD, L
t
WD, p
T
WI, tr
T
WD, L
t=VV(DU -DWL )
Ι
D, wc
T=VV(DU -DWL )
Ι
D, wd
DU
V
VDWL
Ι
Ι
WI, tr CD;; D
C
D
C
t
t
t
t
t
TLE 4278 G
Data Sheet 15 Rev. 1.4, 2007-02-19
Table 5 Hints for Unused Pins
Symbol Function Connect to
RO Reset output open
D Reset delay open or to output Q
RADJ Reset switching threshold adjust GND
WI Watchdog input GND
WO Watchdog output open
WADJ Watchdog adjust 1) to output Q via a 270 kΩ resistor:
Watchdog always active
2) to GND: Watchdog disabled
Data Sheet 16 Rev. 1.4, 2007-02-19
TLE 4278 G
Drop Voltage Vdr versus
Output Current IQ
Current Consumption Iq
versus Input Voltage VI
Current Consumption Iq
versus Output Current IQ
Output Voltage VQ
versus Input Voltage VI
AED01544
0
0
=125
V
dr
T
mV
C
100
200
300
400
500
600
700
Q
Ι
50 100 150 200 mA
C
T25
=
250
j
j
AED01546
0
0
= 33
ΩR
I
q
2
4
6
8
10
12
10 20 30 40 50
L
L
RΩ
= 50
L
RΩ
= 100
T
j
= 25 ˚C
mA
V
I
V
0.1
I
Q
[mA]
110
TLE4278_IQ -IQ.VSD
1
0.1
0.01
10
100
I
q
[mA]
V
I
= 13.5V
T
j
= 25°C
AED01547
0
0
V
Q
V
2
4
6
8
10
mA
246 8 V
Ι
L
R
Ω
33=
Data Sheet 17 Rev. 1.4, 2007-02-19
TLE 4278 G
Charge Current ID,wc and Discharge
Current ID,wd versus Temperature Tj
Output Voltage VQ versus
Temperature Tj
Switching Voltage VDU, VDWL and VDRL
versus Temperature Tj
Output Current Limit IQ versus
Input Voltage VI
3
2
1
0
-40 0 40
7
6
5
4
8
Ι
= 1.0 V
V
Ι
Ι
D, wd
D, wc
D
13.5 V
V
Ι
=
j
12080
T
C
AED03111
A
µ
AED03056
-40
4.6
V
Q
4.7
4.8
4.9
5.0
5.1
5.2
04080 120 160
13.5 V
Ι
V=
T
j
V
˚C
AED03055
-40
0
= 13.5 V
V
D
T
3.2
040
80 120 ˚C
V
Ι
0.4
0.8
1.2
1.6
2.0
2.4
2.8
DU
V
DWL
V
V
DRL
j
V
160
AED03057
0
0
I
Q
10 20 30 40 50
T
j
= 25 ˚C
V
100
200
300
400
500
mA
I
V
Data Sheet 18 Rev. 1.4, 2007-02-19
TLE 4278 G
Package Outlines
Figure 9 PG-DSO-14-30 (Plastic Dual Small Outline) (RoHS compliant)
Green Product
To meet the world-wide customer requirements for environmentally friendly products
and to be compliant with government regulations the device is available as a green
product. Green products are RoHS-Compliant (i.e Pb-free finish on leads and suitable
for Pb-free soldering according to IPC/JEDEC J-STD-020).
±0.08
±0.2
Does not include plastic or metal protrusion of 0.15 max. per side
Index Marking
-0.06
1.27
+0.1
0
.41 C
0.1
-0.2
8.75
1
14
7
1) A
M
0.2
8
A
0.1 MIN.
(1.5)
C
14x 6
1.75 MAX.
4
1)
-0.2
0.33
±0.25
0.64
0.2
+0.05
-0.01
x 45˚
MAX.8˚
1)
GPS09033
TLE 4278 G
Data Sheet 19 Rev. 1.4, 2007-02-19
TLE 4278 G
Revision History: 2007-02-19 Rev. 1.4
Previous Version: 1.3
Page Subjects (major changes since last revision)
general Updated Infineon logo
#1 Added “AEC” and “Green” logo
#1 Added “Green Product” and “AEC qualified” to the feature list
#1 Updated Package Names to “PG-DSO-14-30”
#18 Added “Green Product” remark
You can find all of our packages, sorts of packing and others in our
Infineon Internet Page “Products”: http://www.infineon.com/products.
Dimensions in mm
SMD = Surface Mounted Device
Edition 2007-02-19
Published by Infineon Technologies AG,
81726 München, Germany
© Infineon Technologies AG 2007.
All Rights Reserved.
Attention please!
The information herein is given to describe certain components and shall not be considered as a guarantee of
characteristics.
Terms of delivery and rights to technical change reserved.
We hereby disclaim any and all warranties, including but not limited to warranties of non-infringement, regarding
circuits, descriptions and charts stated herein.
Information
For further information on technology, delivery terms and conditions and prices please contact your nearest
Infineon Technologies Office (www.infineon.com).
Warnings
Due to technical requirements components may contain dangerous substances. For information on the types in
question please contact your nearest Infineon Technologies Office.
Infineon Technologies Components may only be used in life-support devices or systems with the express written
approval of Infineon Technologies, if a failure of such components can reasonably be expected to cause the failure
of that life-support device or system, or to affect the safety or effectiveness of that device or system. Life support
devices or systems are intended to be implanted in the human body, or to support and/or maintain and sustain
and/or protect human life. If they fail, it is reasonable to assume that the health of the user or other persons may
be endangered.
