NCV8508
5.0 V, 250 mA LDO with
Watchdog and RESET
The NCV8508 is a precision micropower Low Dropout (LDO)
voltage regulator. The part contains many of the required features for
powering microprocessors. Its robustness makes it suitable for severe
automotive environments. In addition, the NCV8508 is ideal for use in
battery operated, microprocessor controlled equipment because of its
extremely low quiescent current.
Features
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MARKING
DIAGRAMS
16
16
1
SO-16L
DW SUFFIX
CASE 751G
NCV85085
AWLYYWWG
•
•
•
•
•
•
•
•
•
•
•
•
Output Voltage: 5.0 V
±3.0%
Output Voltage
I
OUT
Up to 250 mA
Quiescent Current Independent of Load
Micropower Compatible Control Functions:
♦
Wakeup
♦
Watchdog
♦
RESET
Low Quiescent Current (100
mA
typ)
Protection Features:
♦
Thermal Shutdown
♦
Short Circuit
♦
45 V Operation
Internally Fused Leads in SO-16L Package
NCV Prefix for Automotive and Other Applications Requiring Site
and Change Control
AEC Qualified
PPAP Capable
Pb-Free Package is Available*
MRA4004T3
NCV8508
C1*
0.1
mF
V
IN
V
OUT
WDI
Delay
R
Delay
60 k
GND
RESET
WAKEUP
C2
1.0
mF
V
DD
I/O
RESET
I/O
1
NCV85085
AWLYWWG
D
2
PAK-7
DPS SUFFIX
CASE 936AB
1
8
8
1
SO-8 EP
PD SUFFIX
CASE 751AC
1
V8508
ALYW
G
V
BAT
Microprocessor
A
WL, L
YY, Y
WW, W
G or
G
= Assembly Location
= Wafer Lot
= Year
= Work Week
= Pb-Free Package
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 23 of this data sheet.
*C1 required if regulator is located far from power supply filter.
Figure 1. Application Circuit
*For additional information on our Pb-Free strategy and soldering details, please
download the ON Semiconductor Soldering and Mounting Techniques
Reference Manual, SOLDERRM/D.
©
Semiconductor Components Industries, LLC, 2007
1
October, 2007 - Rev. 25
Publication Order Number:
NCV8508/D
NCV8508
PIN CONNECTIONS
1
NC
NC
NC
GND
GND
NC
Sense
V
OUT
SO-16L
16
Delay
RESET
Wakeup
GND
GND
WDI
NC
V
IN
1
Tab = GND
Lead
1. V
OUT
2. V
IN
3. WDI
4. GND
5.
Wakeup
6.
RESET
7. Delay
D
2
PAK-7
1
Delay
GND
Sense
V
OUT
8
RESET
Wakeup
WDI
V
IN
SO-8 EP
PACKAGE PIN DESCRIPTION
PACKAGE PIN #
D
2
PAK-7
1
2
3
4
5
SO-16L
8
9
11
4, 5, 12, 13
14
SO-8 EP
4
5
6
2
7
PIN SYMBOL
V
OUT
V
IN
WDI
GND
Wakeup
FUNCTION
Regulated output voltage
±
3.0%.
Supply Voltage to the IC.
CMOS compatible input lead. The Watchdog function
monitors the falling edge of the incoming signal.
Ground connection.
CMOS compatible output consisting of a continuously
generated signal used to “wake up” the microprocessor
from sleep mode.
CMOS compatible output lead RESET goes low whenever
V
OUT
drops by more than 7.0% from nominal, or during the
absence of a correct Watchdog signal.
Buffered bandgap voltage used to create timing current for
RESET and Wakeup from R
Delay.
No Connection.
Kelvin connection which allows remote sensing of the
output voltage for improved regulation. Connect to V
OUT
if
remote sensing is not required.
6
15
8
RESET
7
-
-
16
1-3, 6, 10
7
1
-
3
Delay
NC
Sense
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2
NCV8508
V
IN
-
+
Charge
Pump
11 V
1.25 V
+
-
Internally
connected
on 7 lead
D
2
PAK
Current
Limit
Thermal
Shutdown
V
OUT
Sense
Bandgap
Reference
RESET
+
WDI
Falling
Edge
Detect
Timing
Circuit
Delay
MAXIMUM RATINGS
Rating
Input Voltage, V
IN
(DC)
Peak Transient Voltage (46 V Load Dump @ V
IN
= 14 V)
Output Voltage, V
OUT
ESD Susceptibility:
Human Body Model
Machine Model
Logic Inputs/Outputs (RESET, WDI, Wakeup)
Operating Junction Temperature, T
J
Storage Temperature Range, T
S
Peak Reflow Soldering Temperature:
Reflow: (Note 1)
2.0
150
-0.3 to +7.0
-40 to150
-55 to +150
240 Peak
260 Peak (Pb-Free)
(Note 3)
kV
V
V
°C
°C
°C
Value
-0.3 to 45
60
-0.3 to 18
Unit
V
V
V
Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the
Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect
device reliability.
1. 60 second maximum above 183°C.
2. Depending on thermal properties of substrate R
qJA
= R
qJC
+ R
qJCA
.
3. -5°C/+0°C allowable conditions, applies to both Pb and Pb-Free devices.
THERMAL CHARACTERISTICS
See Package Thermal Data Section (Page 10)
-
Watchdog
Circuit
Wakeup
Circuit
Wakeup
Figure 2. Block Diagram
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NCV8508
ELECTRICAL CHARACTERISTICS
(-40°C
≤
T
J
≤
125°C; 6.0 V
≤
V
IN
≤
28 V, 100
mA
≤
I
OUT
≤
150 mA, C
2
= 1.0
mF,
R
Delay
= 60 k;
unless otherwise specified.)
Characteristic
OUTPUT
Output Voltage
Dropout Voltage (V
IN
- V
OUT
)
Load Regulation
Line Regulation
Current Limit
Thermal Shutdown
Quiescent Current
RESET
Threshold
Output Low
Output High
Delay Time
-
R
LOAD
= 10 k to V
OUT
, V
OUT
≥
1.0 V
R
LOAD
= 5.1 k to V
OUT
, V
OUT
≥
1.0 V
R
LOAD
= 10 k to GND
R
LOAD
= 5.1 k to GND
V
IN
= 14 V, R
Delay
= 60 k, I
OUT
= 5.0 mA
V
IN
= 14 V, R
Delay
= 120 k, I
OUT
= 5.0 mA
4.50
-
V
OUT
- 0.5
V
OUT
- 1.0
2.0
-
4.65
0.2
0.4
V
OUT
- 0.25
V
OUT
- 0.5
3.0
6.0
4.80
0.4
0.8
-
4.0
-
V
V
V
ms
ms
-
I
OUT
= 150 mA. Note 4
V
IN
= 14 V, 100
mA
≤
I
OUT
≤
150 mA
6.0 V
≤
V
IN
≤
28 V, I
OUT
= 5.0 mA
-
Guaranteed by Design
V
IN
= 12 V, I
OUT
= 150 mA, (see Figure 6)
4.85
-
-
-
250
150
-
5.00
450
5.0
5.0
400
180
100
5.15
900
30
50
-
210
150
V
mV
mV
mV
mA
°C
mA
Test Conditions
Min
Typ
Max
Unit
WATCHDOG INPUT
Threshold High
Threshold Low
Hysteresis
Input Current
Pulse Width
WDI = 6.0 V
50% WDI falling edge to
50% WDI rising edge and
50% WDI rising edge to
50% WDI falling edge, (see Figure 5)
-
-
-
70
-
-
-
5.0
-
-
100
0.1
-
-
30
-
+10
-
%V
OUT
%V
OUT
mV
mA
ms
WAKEUP OUTPUT
(V
IN
= 14 V, I
OUT
= 5.0 mA)
Wakeup Period
Wakeup Duty Cycle Nominal
RESET HIGH to
Wakeup Rising Delay Time
See Figures 4 and 5, R
DELAY
= 60 k
See Figures 4 and 5, R
DELAY
= 120 k
See Figure 3
R
DELAY
= 60 k
50% RESET rising edge to
50% Wakeup edge, R
DELAY
= 120 k
(see Figures 3 and 4)
50% WDI falling edge to
50% Wakeup falling edge
50% RESET falling edge to
50% Wakeup falling edge.
V
OUT
= 5.0 V→ 4.5 V
R
LOAD
= 10 k to V
OUT
, V
OUT
≥
1.0 V
R
LOAD
= 5.1 k to V
OUT
, V
OUT
≥
1.0 V
R
LOAD
= 10 k to GND
R
LOAD
= 5.1 k to GND
18
-
45
9.0
-
25
50
50
12.5
25
32
-
55
16
-
ms
ms
%
ms
ms
Wakeup Response to
Watchdog Input
Wakeup Response to RESET
-
-
0.1
0.1
5.0
5.0
ms
ms
Output Low
Output High
DELAY
Output Voltage
-
V
OUT
- 0.5
V
OUT
- 1.0
0.2
0.4
V
OUT
- 0.25
V
OUT
- 0.5
0.4
0.8
-
V
V
I
DELAY
= 50
mA.
Note 5
-
1.25
-
V
4. Measured when the output voltage has dropped 100 mV from the nominal value. (see Figure 12)
5. Current drain on the Delay pin directly affects the Delay Time, Wakeup Period, and the RESET to Wakeup Delay Time.
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NCV8508
TIMING DIAGRAMS
V
IN
RESET
Wakeup
Duty Cycle = 50%
Wakeup
WDI
V
OUT
POR
RESET High
to Wakeup
Delay Time
Power Up
Microprocessor
Sleep Mode
WDI Pulse Must Occur with Wakeup in
Low State for 50% Duty Cycle.
Reference Figure 17 for Occurrence of
WDI with Wakeup in High State.
Normal Operation with Varying Watchdog Signal
Figure 3. Power Up, Sleep Mode and Normal Operation
V
IN
RESET
Wakeup
WDI
RESET Delay Time
V
OUT
POR
RESET High
to Wakeup
Delay Time
Wakeup
Period
RESET High
to Wakeup
Delay Time
Figure 4. Error Condition: Watchdog Remains Low and a RESET Is Issued
RESET
Wakeup
Wakeup Period
WDI
RESET Threshold
V
OUT
Watchdog
Pulse Width
POR
Watchdog Pulse Width
Power Down
POR
Figure 5. Power Down and Restart Sequence
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