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L9468
April 2005
1
Features
FULLY MONOLITHIC DESIGN
HIGH SIDE FIELD DRIVE
THERMAL PROTECTION
FIELD DRIVER SHORT CIRCUIT
PROTECTION
PROTECTED DIAGNOSTIC LAMP DRIVER
REDUCED OUTPUT MODE
COMPLEX DIAGNOSTICS
LOAD RESPONSE CONTROL
2
Description
The L9468 is a monolithic multifunction generator
Voltage regulator intended for use in automotive ap-
plications.
This device regulates the output of an automotive
generator by controlling the field winding current by
means of a variable frequency PWM high side driver.
ALL SILICON VOLTAGE REGULATOR
Figure 2. Block Diagram
FIELD
(ROTOR)
STARTER
BATTERY
STATOR
ASVR
LOADS
RECTIFIER
BRIDGE
KEY SW
F
M
S
F+
L
V
GO
P
G
TO ECM
FAULT
LAMP
D02AT503
Figure 1. Package
Table 1. Order Codes
Part Number
Package
L9468N
Multiwatt8
Multiwatt8
Rev. 1
L9468
2/8
Table 2. Pin Description
Table 3. Absolute Maximum Ratings
Figure 3. Pin Connection (Top view)
Table 4. Thermal Data
N
Pin
Function
1
V
GO
Generator output sense and voltage supply to L9468
2
F+
Field high side driver output
3
G
Ground for L9468
4
S
Battery sense input
5
GND
Connected to the Tab through the frame
6
F
M
Field monitor output
7
L
Lamp terminal low side driver
8
P
Phase sense input
Symbol
Parameter
Value
Unit
V
S
Thermal Supply Voltage (load dump)
40
V
I
O
Output Current Capability
internally limited
A
P
tot
Total Power Dissipation (@T
case
= 150C, I
FIELD
= 5A)
6
W
V
R
Reverse Voltage (see figure 1)
-2.5/-6
V
Symbol
Parameter
Value
Unit
R
th j-case
Thermal Resistance junction-case
-45 to 160
C
T
stg
Storage Temperature
-50 to 175
C
R
th sd
Thermal Shut-Down
175
15
C
R
th j-case
Thermal Resistance junction -case
1.5
C/W
1
2
3
4
5
6
7
D02AT504
8
P
L
F
M
GND
S
G
F+
V
GO
Tab connected to pin 5
3/8
L9468
Notes:
1. 20 Volts is the maximum operating voltage because above this level the FAILSAFE feature shuts down the output stage.
2. Thermal slopes are shown in fig. 2
3. This value is present when the voltage sensed at the " S" or "VGO" terminal is between VUV and VOV. When the voltage sensed
at the "S" or "VGO" terminal is above VOV the Minimum Field Duty-Cycle will be 0 %.
Figure 4. Reverse B+ Test Circuit
Table 5. Electrical Characteristcs
(T
case
= -35C to 150C unless otherwise specified)
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
V
OS
Operating Supply Voltage
T
case
= +25 to +150 C
8
20
1
V
V
OS
Operating Supply Voltage
T
case
= - 40 to +25 C
10
20
V
I
SB
Stand-by Current
V
GO
= 12.6V, T
case
-35
to +80 C
400
A
I
SB
Stand-by Current
V
GO
= 12.6 V, 80C <T
case
< +150C
1
mA
V
S
Regulator Set-Point
@ 71C 3C
14.1
V
V
NB
Generator output, no battery
No battery, I
OUT
=2A to 50% Max
Load
V
S
-2
V
S
+2
V
T
C
Thermal compensation
Voltage @ V
S
or V
GO
2
in failsoft
V
V
LR
Load Regulation
6500 grpm, 10% to 95% load
300
mV
V
SR
Speed Regulation
15A load, 2,000 to 10,000 grpm
100
mV
V
FON
Output Saturation Voltage
I
F
= 6A, V
GO
= 14.7V, T
case
= 25C
750
mV
V
FON
Output Saturation Voltage
I
F
= 5A, V
GO
= 13.5V, T
case
= 125C
850
mV
I
FLIM
Field limit current
F terminal shorted to GND @ 25C
8.3
A
F terminal shorted to GND @ 150C
5
A
V
F
Field Discharge Rectifier
I
F
= 6A, T
case
= 25C
1.85
V
I
R
Diode
Reverse
Current
V
R
= 20V
1
mA
f
OSC
Oscillation frequency
During LRC operation
340
400
460
Hz
MFDC
Minimum Field Duty-Cycle
V
UV
< V(S or V
GO
) < V
OV
3
6.25
%
R
FM
Impedance
@
F
M
pin
Impedance between F
M
and F+
5
15
K
1.8
FIELD
ASVR
F
M
S
F
L
I
P
V
GO
F
G
INCANDESCENT
LOAD 14
D02AT505
POWER SUPPLY
6V
+
-
POWER SUPPLY
2.5V
-
+
L9468
4/8
Figure 5. Setpoint Voltage vs. T
case
Temperature
Table 6. Diagnostic (T
case
-35C to +150C unless otherwise specified)
Notes:
4. When Fail Soft operation is detected, regulation sensing will switch from the "S" terminal to the VGO terminal.
5. This condition can happen when the connection between the battery and VGO or the output terminal of the generator is broken.
In this case the delay of 1.1 seconds is not required.
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
V
FSO
Failsafe Output Voltage
Voltage measured at V
GO
20
20.48
21
V
V
FSL
Switch sensing from S to V
GO
"S" Voltage falling into Fail Soft
4
4
4.2
V
V
FSH
Switch sensing from V
GO
to S
"S" Voltage rising out of Fail Soft
7.6
8
V
I
S
Sink current @ "S" pin
V
S
= 14 V
1
1.75
2.5
mA
V
UV
Undervoltage
grpm > 3100 15%
10.95
11.35
11.6
V
V
OV
Overvoltage
V
S
+1
V
S
+1.25
V
S
+1.55
V
V
LSAT
Lamp saturation voltage
I
L
= 0.5A
1.33
1.4
V
V
LSAT
Lamp on Voltage
5
I
L
< 0.5A,VGO=open, T
case
=
25C
3.8
5
V
T
DELAY
Fault Indication Delay Time
0.935
1.1
1.265
s
0
20
40
60
80
100
120
Tcase(C)
-40
13.0
13.2
13.4
13.6
13.8
14.0
14.2
14.4
14.6
14.8
15.0
15.2
15.4
15.6
15.8
V
S
(V)
-20
D02AT506
15.9
15.45
15.05
14.35
14.1
13.85
14
13.65
13.35
14.8
14.55
15
5/8
L9468
3
FAULT
The following table lists the conditions that cause the fault lamp driver to function. To prevent lamp flicker, spe-
cific faults are required to be present for TDELAY seconds before the lamp driver is activated. This delay is
indicated in the table.
Table 7.
Table 8. Regulation Features
Notes:
6.
Lamp and Ignition are cooperative. Either can turn on the device when the other is left open or held low. When both go below
their minimum thresholds the L9468 goes into "L" Terminal Control (LTC). The L9468 will remain in LTC until the phase (P) voltage
drops below VP2 and the frequency drops below fIRF at the VP1 threshold then the L9468 is disabled.
7.
This threshold on the phase signal is used to detect the phase frequency, fIFR, for the Initiation of field regulation.
8.
This threshold on the phase signal is used to sense the presence of the phase for fault detection purposes.
9.
This is the time duration the L9468 takes to rump up from 0 % to 100% duty cycle in response to an increased load on the enerator.
The LRC ratio is set 1:4 and the Vreg comparator status is latched at foundamental frequency rate.
10. Cut-back occurs when both the "L" and "I" terminals are LOW . If the "I" terminal is disconnected it will assume a logic LOW
allowing the "L" terminal to perform the function alone. In cut-back, to prevent the loss of phase signal, a 31.25% duty cycle is
applied to field output when phase drops below Vp2
Conditions
Delay
1. Key-on (wiring check), lamp stays on for 1 0.15 sec regardless
other conditions
No
2. V
GO
/ S> V
OV
Yes
3. V
GO
/ S < undervoltage threshold voltage AND Phase frequency > f
LRC
Yes
4. Phase Voltage < VP2 AND VGO
/ S < setpoint
Yes
5. Phase frequency < f
IFR
Yes
6. No connection between Battery and VGO
No
7. FAILSAFE
Yes
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
V
LON
Lamp term turn on threshold
6
0.8
1
1.15
V
I
LON
Lamp term current sensitivity
V
L
= 1 V to Vsp
0.09
0.78
mA
V
P1
Initiation of regulation detection
phase voltage threshold
7
I
P
= 1mA (sinking current)
2.5
3
3.5
V
V
P2
Fault detection phase voltage
threshold
8
7
8
9
V
I
P
Sinking current @ P terminal
V
P
= 1.5V
0.5
1
1.8
mA
f
IFR
Initiation of field regulation
frequency
53.04
61
70.15
Hz
FSDF
Field Strobe Duty Factor
@ "power up" with f
PHASE
< f
IFR
31.25
%
LRC
Load Response Control rate
9
2.125
2.5
2.875
s
f
LRC
LRC transition frequency
LRC is enabled below this value
263.5
310
356.5
Hz
V
LCB
"L" term. Cut-Back Setpoint
"L" = 0V, "I" = 0V
10
V
S
-
20%
V
S
-
25%
V
S
-30%
V
L9468
6/8
4
Package Information
Figure 6. Multiwatt 8 Mechanical Data & Package Dimensions
OUTLINE AND
MECHANICAL DATA
0043674 F
*
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
5
0.197
B
2.65
0.104
C
1.6
0.063
E
0.49
0.55
0.019
0.022
F
0.78
0.85
0.030
0.033
F1
0.68
0.75
0.027
0.029
G
2.40
2.54
2.68
0.094
0.10
0.105
G1
17.64
17.78
17.92
0.69
0.70
0.71
H1
19.6
0.772
H2
20.2
0.795
L
20.35
20.65
0.80
0.81
L2
17.05
17.20
17.35
0.67
0.68
0.68
L3
17.25
17.5
17.75
0.679
0.689
0.699
L4
10.3
10.7
10.9
0.406
0.421
0.429
L5
15.45
15.75
0.61
0.62
L5*
15.05
15.35
0.59
0.60
L7
2.65
2.9
0.104
0.114
S
1.9
2.6
0.075
0.102
S1
1.9
2.6
0.075
0.102
U
0.40
0.55
0.015
0.022
Z
0.70
0.85
0.028
0.034
Dia1
3.65
3.85
0.144
0.152
L5 = with wedged frame std.
L5* = with wedged frame anchor holes.
Multiwatt8 (Floating)
7/8
L9468
5
Revision History
Table 9. Revision History
Date
Revision
Description of Changes
April 2005
1
First Issue
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of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted
by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject
to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not
authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.
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L9468
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