STMICROELECTRONICS L9474

L9474
ALL SILICON VOLTAGE REGULATOR
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Figure 1. Package
Features
High side field driver
Thermal protection
Field driver short circuit protection
RVC interface
Overvoltage protection
Complex diagnostics
Load Response Control
Multiwatt8
Description
Table 1. Order Codes
The L9474 is a monolithic multifunction generator
Voltage regulator intended for use in automotive applications.
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.
Part Number
Package
L9474
Multiwatt8
The setpoint voltage reference is selected by the ENGINE CONTROL UNIT via RVC protocol.
Figure 2. Schematic Diagram
TO ECM
L
VGO
STARTER
TO ECM
FM
ASVR
F+
TO BCM
BATTERY
P
STATOR
LOADS
FILTER
FIELD
(ROTOR)
G
C
82nF
RECTIFIER
BRIDGE
D02AT508
March 2005
Rev. 1
1/8
L9474
Table 2. Pin Description
N°
Pin
Function
1
P
Phase sense input
2
L
Warning terminal output and ECM PWM input
3
FM
4
RESERVED
5
GND
6
FILTER
7
F+
8
VGO
Field monitor output
Reserved
Regulation loop filter
Field high side driver output
Generator output sense and voltage supply to L9474
Table 3. Absolute Maximum Ratings
Symbol
Parameter
VS
Transient Supply Voltage (load dump)
IO
Output Current Capability
Ptot
VREV
Value
Unit
40
V
Internally limited
A
6
W
-2.5 to -6
V
Value
Unit
Power Dissipation (@Tj = 150°C, IField = 6A)
Reverse Voltage (see fig.1)
Figure 3. Pin Connection (Top view)
8
VGO
7
F+
6
FILTER
5
GND
4
RESERVED
3
FM
2
L
1
P
D02AT509
Table 4. Thermal Data
Symbol
Tj
Junction temperature
-40 to 150
°C
Tstg
Storage Temperature
-50 to 150
°C
Tsd
Thermal Shut Down
175 ±15
°C
1.5
°C/W
Rth j-case
2/8
Parameter
Thermal Resistance Junction to Case
L9474
Table 5. Electrical Characteristcs (Tj -35°C to +150°C unless otherwise specified)
Symbol
Parameter
VOS
Operating Supply Voltage
ISB
Stand-by Current 2
Test Condition
Min.
Typ.
8
VGO = 12.6V, Tcase -35 to +80°C
VGO = 12.6 V, 80 <Tcase< +150 °C
Max.
Unit
161
V
400
µA
1
mA
VSF
Regulator Set-Point in Fault
PWM signal loss
VNB
Generator output, no battery
No battery, IOUT =2A to 50% max
load
TC
Thermal compensation
Driven by ECM
VLR
Load Regulation
6500 grpm, 10% to 95% load
300
mV
VSR
Speed Regulation
15A load, 2,000 to 10,000 grpm
100
mV
VFON
Output Saturation Voltage
IF = 9A, Tcase < = 25°C
750
mV
VFON
Output Saturation Voltage
IF = 6A, Tcase > 25°C
850
mV
IFLIM
Field limit current
F shorted to gnd, Tcase < = 25°C
9
A
F shorted to gnd, Tcase = 150 °C
6
A
13.8
Field Discharge Rectifier
IF =6A, Tcase = 25 °C
IR
Diode Reverse Current
VR = 16 V
Oscillation frequency
During LRC operation
Minimum Field Duty-Cycle
V(VGO) < VOV 3
Impedance @ FM pin
Impedance between FM and F+
MFDC
RFM
VS+2
RVC or FLAT
VF
fOSC
VS-2
V
340
400
V
1.85
V
1
mA
460
Hz
6.25
0.8
V
%
2.5
KΩ
Notes:
1. 16 Volts is the maximum operating voltage.
2. Stand-by current measured with L, FM open; F connected to gnd; P open or tied to gnd.
3. When the voltage sensed at VGO terminal is above VOV the Minimum Field Duty-Cycle will be 0 %.
Figure 4. Reverse B+ Test Circuit
+
POWER SUPPLY
6V
-
POWER SUPPLY
2.5V
-
+
VGO
L
P
FILTER
ASVR
FM
F
C
82nF
1.8Ω
FIELD
G
D02AT510
3/8
L9474
Figure 5. Setpoint Voltage vs. L terminal signal
Table 6. Diagnostic (Tj -35°C to +150°C unless otherwise specified)
Symbol
VOV
Parameter
Test Condition
L Saturation Voltage
TDELAY
Fault Indication Delay Time
Typ.
16.5
Overvoltage4
VLSAT
Min.
IL = 50 mA
0.935
1.1
Max.
Unit
22
V
1.35
V
1.265
s
Note:
4. When the Vgo voltage overcomes this value the MFDC is cancelled
Table 7. FAULT
The following table lists the conditions that cause the fault driver to function (L terminal now switching be-tween
0V and VLSAT. To prevent L flicker, specific faults are required to be present for TDELAY seconds be-fore the
fault driver is activated. This delay is indicated in the table.
Conditions
Delay
1. Key-on (RVC PWM signal acknowledgement)
No
2. Phase Voltage < VP2 AND VGO < setpoint
Yes
4/8
L9474
Table 8. Regulation Features
Symbol
VLON
Parameter
Lamp term turn on 5 threshold
ILON
VP1
Initiation of regulation detection
phase voltage threshold 6
VP2
Fault detection phase voltage
threshold 7
IP
Sinking current @ P terminal
fIFR
FSDF
Test Condition
Min.
Typ.
Max.
Unit
fL = 128Hz +/-5%
0.65
0.9
1.15
V
VL = 0.65V
0.3
1.5
mA
IP = 1mA (sinking current)
VP = 1.5V
0.35
7
8
9
V
0.5
1
1.8
mA
Initiation of field regulation
frequency
Field Strobe Duty Factor
LRC
Load Response Control rate 8
fLRC
LRC transition frequency
∆gnd
Difference between ECM &
Alternator ground
@ "power up" with fPHASE < fIFR
LRC disabled above this value
V
72
Hz
12.5
%
2.125
2.5
2.875
s
263
310
357
Hz
0.2
V
-0.2
Notes:
5. A 128Hz PWM signal applied to L input, higher than this threshold, will turn on the device.
6. This threshold on the phase signal is used to detect the phase frequency, fIFR, for the Initiation of field regulation.
7. This threshold on the phase signal is used to sense the presence of the phase for fault detection purposes. Furthermore, to prevent
the loss of phase signal, a 31.25% duty cycle is applied to field output when phase drops below Vp2 and Vgo is above setpoint.
8. This is the time duration the L9474 takes to rump up from 0 % to 100% duty cycle in response to an increased load on the generator. The LRC ratio is set 1:4 and the Vreg comparator status is latched at foundamental frequency rate.
5/8
L9474
3
Package Information
Figure 6. Multiwatt8 Mechanical Data & Package Dimensions
DIM.
mm
MIN.
TYP.
inch
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
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
0.029
0.772
H2
20.2
L
20.35
L2
17.05
L3
L4
OUTLINE AND
MECHANICAL DATA
0.795
20.65
0.80
17.20
17.35
0.67
0.81
17.25
17.5
17.75
0.679
0.689
0.699
10.3
10.7
10.9
0.406
0.421
0.429
0.68
0.68
L5
15.45
15.75
0.61
L5*
15.05
15.35
0.59
0.62
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
Multiwatt8 (Floating)
*
L5 = with wedged frame std.
L5* = with wedged frame anchor holes.
0043674 F
6/8
L9474
4
Revision History
Table 9. Revision History
Date
Revision
March 2005
1
Description of Changes
First Issue
7/8
L9474
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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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