Datasheet L584 Datasheet (SGS Thomson Microelectronics)

MULTIFUNCTIONINJECTION INTERFACE

.DRIVES ONE OR TWO EXTERNAL DAR-

LINGTONS

.DUAL AND SINGLE LEVEL CURRENT CON-

TROL

.SWITCHMODECURRENTREGULATION

.ADJUSTABLEHIGHLEVELCURRENT DURA-

TION

.WIDE SUPPLYRANGE(4.75 - 46V)

.TTL-COMPATIBLELOGICINPUTS

.THERMAL PROTECTION

.DUMP PROTECTION

DESCRIP TIO N

TheL584 is designedto drive injectorsolenoidsin
electronic fuel injection systems and generally in­ductiveloads for automotive applications.The de­vice is controlled by two logic inputs and features
switchmoderegulationoftheloadcurrentdrivingan
externaldarlingtonandan auxiliaryonefor the cur­rent recirculation.A key featureof the L584is flexi­bility. It canbe used with a varietyof darlingtonsto
match the requirements of the load and it allows
bothsimpleandtwolevelcurrentcontrol.Moreover,

L584

PRELI MINA RY DATA

DIP16 (12+2+2)

ORDERING NUMBER : L584

the drive waveshape can be adjusted by external
components.Other features of the device include
dump protection,thermal shutdown, a supply vol­tagerangeof4.75-46VandTTL-compatibleinputs.
TheL584is suppliedin a16leadPowerdippackage
whichuses the four center pins to conduct heat to
the PC board copper.

BLOCK DIAG RAM

November 1988

1/13

L584

PIN CO NNEC TIO N

ABSOLUTE MAXIMUMRATINGS

Symbol Parameter Value

V

V

V

V

sens

V

I

Tstg,Tj Storageand Junction Temperature Range –55 to 150°C

DC Supply Voltage (pin 1 open)

S

– 0.2Vmin; +50V Max
PositiveTransient Voltage
(pin 1 connected to V
(5ms ≤ t

Input Voltage(pins 10, 11) – 0.2V min;+7V Max

1

ExternalReference Voltage (pin 2) – 0.2V min;+7V Max

r

≤ 10ms,R

rise

, πffalltime constant = 100ms)

S

≥ 0.5Ω)

source

SenseVoltage (pin 3) – 0.2V min;+7V Max
Max D.C. and Transient Voltage 50V

8

ReferenceCurrent (pin 9) 5mA Max

r

+60VMax

THERMAL DATA

Symbol Parameter Value Unit

R

th j-pins

R

th j-amb

* Obtained with the GND pins soldered to printed circuitwith minimized copper area.

2/13

ThermalResistance Junction-pins Max. 15 °C/W
ThermalResistance Junction-ambient Max. 80 °C/W

PIN FUNCTIONS

o

N

Name Functions

1 Dump Protection With pin 1 connected to pin 14 the device is protectedagainst dump voltage ≤ 60V.

Theprotectio.n operates at V

≥ 32V(typ.).If this protectionis notused thepin must

S

beleft open

2 HoldingCurrent Control Thevoltage V

appliedto this pin sets the holding current level.

set

3 Sensing Connection for load current sense resistor. Vazlue sets thepeak and holding current

levels. I

=0.45/RS(typ.);Ih=V

P

. (see block diagram and fig. 4).

set/Rs

4 Ground Ground Connection. With pins 5, 12 and13 conducts heat to pc board copper.
5 Ground See pin 4.
6 PeakCurrent Timer A capacitorconnected between this pin andgroundsets the duration of the high level

current(t

7 Discharge Time Constant A capacitor connected between this pin and ground sets the duration of t

infig. 4)

2

off

grounded, the current switchmode control is suppressed.

8 PNP DrivingOutput Current sink for external PNPdarlington (for recirculation). I

= 35 Ir (typ).

dp

9 ReferenceVoltage A resistorconnected between this pin and ground setsthe internal current reference,

I

. The recommended value is 1.2kΩ givingIr = 1mA (typ.).

r

10 Input TTL-compatible Input. A highlevel on this pin activatesthe output, drivingthe load.
11 Inhibit TTL-compatible Inhibit Input.A high level on this input disablesthe output stagesand

logic circutry, irrespectiveof the state of pin 10.

12,13 Ground See Pin 4.

14 Supply Voltage Supply Voltage Input.
15 NPN Driving Output Current Source for ExternalNPN Darlington (load driver).I

=100 Ir(typ.)

dn

16 Internal Clamping Internal Clamp Zener for Fast Turn-off.

000

L584

(fig.4). If

3/13

L584

ELECTRICAL CHARACTERISTICS (Vs(Pin 14) = 14.4V; –40 ≤ Tj ≤ 105°C; R

= 1.20KΩ unless

ref

otherwise specified; refer to fig. 1)

Symbol Parameter Test Condiction Min. Typ. Max. Unit

OperatingSupply Voltage Pin1 Open 4.75 44 V

V

S

V

V

V
R

I
V

I

V
R

I

V

6SAT

I

V

7SAT

V
V
V

I

V

I

dn

I

dp

Dump ProtectionThreshold Pin 1 = V

d

Dump ProtectionInput Resistance Pin 1 to GND 18 50 kΩ

d

QuiescentCurrent Pin 14 45 mA

q

Input Threshold Voltages Pin10, 11

i

S

Low
High 2.0

Input Current Pin 10, 11

i

Low
High

ReferenceVoltage Pin 9 1.15 1.35 V

r

ReferenceResistor Range Pin 9 to GND

r

PeakDuration ControlCurrent Pin 6

6

PeakDuration Control

6th

I

r=Vr/Rr

V

≤ 1.8V

pin6

Pin 6 1.20 1.6 V

Comparator Threshold
Pin6 SaturationVoltage Pin 6

(dischargestate)

Off DurationControl Current Pin 7

7

Off DurationControl

7th

V

≤ 1.8V

pin7

Pin 7 1.20 1.6 V

Comparator Threshold
Pin7 SaturationVoltage Pin 7

(dischargestate)

PeakCurrent Threshold Voltage Pin 3 400 500 mV

spt

Holding Current SetVoltage Range Pin 2 0 2 V

set

Holding Current SetVoltage Range Pin 3, Peak Value, dV/dt ≤ 1V/

set

Pin3 Bias Current V

3

Recirculation Zener Clamping

cl

= 600mV –200 µA

pin3

Pin16to Pin15@200mAintoPin16 13.5 18.5 V

s

Voltage
NPN Driver Source Current V

=0V 70xIr| 140 x I

pin15

PNP Driver Sink Current Vpin 8 ≥ 4.75V 25 x Ir|60xI

28 36 V

0.8 V

–100

–250

1 3.3 kΩ

/9.50 | Ir/6.00

I

r

|

200 mV

(I

r min

)/9.50 | (I

r max

)/6.00

|

200 mV

V

set

0.01

–

V

set

0.01

+

r

r

V

µA
µA

A

A

V

A
A

4/13

APP LICATION INF ORMATION

Controlledby alogicinputand an inhibitinput (both
TTL compatible),thedevicedrivestheexternaldar­lington(s) to produce a load current waveform as
shownin figure4. Thisbasicwaveform showsthat
thedeviceproducesaninitialhighlevelcurrentinor­der to ensurea fastopening,followedby a holding
level current as long as the input is active. Both
the peak and holdingcurrent are regulatedby the
L584’sswitchmodecircuitry.

Thedurationof thehighlevelcurrentandthe values
ofthepeakandtheholdingcurrentscanbeadjusted
by externalcomponents.

Moreover,by omitting C1, C2 or bothit is possible
to realize single-level current control, a transitory
peak followed by a regulated holding current or a
simple peak (figure1).

Thepeakandholdingcurrentvaluesare alwaysre-

Figure1 : ComponentsConnectedto Pins 6 and 7 Determinethe LoadCurrent Waveshape.

L584

COMPONENTS ON PINS 6 AND 7

LOAD CURRENT WAVEFORM

5/13

L584

ferred,inthe followingformula,toIE, emittercurrent
of the external darlingtonQ2,

I

E=ILOAD+Idn

becausethe sensingdetectionis on the darlington
emitter(not directlyon theload).

The peak currentlevel I
sistor,R

, and is found from :

s

I

=0.45 /Rs(typ)

p

The peak valueof holdingcurrentlevel,I
a voltage(V

)appliedto pin2, giving :

set

I

hp=Vsetth/Rs

, is set by the sensingre-

p

, is setby

h

=(V

± 10mV)/R

set

s

The peak to hold currentratio is fixed by V

I

=0.45 / V

p/Ihp

V

isfixedby an externalreferenceand a voltage

set

divider(V
V

set=Vext

, R1, R2infig 2) :

ext

* R2 / (R1 + R2)

setth

set

:

Dueto theparticulardarlingtonstoragetimeandthe
devicereactiontimenot very significantdifferences
canbefoundbetweenI

andIhvalues based on the

p

previousformulaand therealvaluesseenin theap­plications.

Ifthe holdingcurrentfunctionisnot used,pin 2can­notbeleftfloatingandit mustbeconnectedto GND.

Figure2 : ApplicationCircuit Showing the OptionalComponents.In particularit illustrates howtheholding

currentlevelis adjustedindependentlyofthepeakcurrent(with R1,R2,V

)andhow theinternal

ext

zenerclamp is connected.This circuit producesthe waveformsshownin Fig.4.

Io(A) Q1 Q2

4 BDX54 BDX53
8 BDW94 BDW93

12 BDV64 BDV65

Figure3 : P.C.Board and ComponentsLayout of theCircuit of Fig. 2 (1 : 1 scale).

6/13

L584

The drive current for the two darlingtons and the
waveformtime constantsareall definedinturn bya
resistorbetweenpin 9 and ground.

The recommendedvalue for I

is1mA whichis ob-

r

tained with a 1.2KΩ resistor. The darlington drive
currentsare givenby :

PNP : I

The durationof the high current level (t

=35Irtyp. NPN: Idn=100Irtyp.

dp

in fig 4) is

2

set by a capacitor connected between pin 6 and

ground.Thiscapacitor,C1 isrelatedtothe duration,
t

,by:

2

t2=C

The dischargetime constant(t
capacitorC
from:

t

=C2

off

Figure4 : Waveformsof the TypicalApplicationCircuit of Fig. 2.

V

6th–V6sat

1

I

6

betweenpin7 andgroundandis found

2

V

7th–V7sat

⋅

I

7

C

= 12 (typ.)

=12

1

I

ref

infig 4) is set by a

off

C

r

(typ)

I

ref

7/13

L584

Figure5 : When pin 6 is grounded,as shownhere, the injector currentis regulatedat a singlelevel.

Io(A) Q1 Q2

4 BDX54 BDX53
8 BDW94 BDW93

10 BDV64 BDV65

Figure6 : In this applicationcircuit, pin 6 is leftopen to givea single peak followedby a regulatedholding

current.

(A) Q1 Q2

I

o

4 BDX54 BDX53
8 BDW94 BDW93

10 BDV64 BDV65

8/13

Figure7 : Switchmodecontrol of the current can be suppressedentirelyby leavingpin 6 open and

groundingpin 7. the peak currentis stillcontrolled.

Io(A) Q1 Q2

4 BDX54 BDX53
8 BDW94 BDW93

10 BDV64 BDV65

L584

Figure8 : Applicationscircuitusing only one darlingtonwith a single level of the injector current.

9/13

L584

To have a very shortoff time when the L584 input
goes LOW,aninternalzener is availableon pin16.
This zeneris usedwithan externaldivider,R8, R9,
as shown in figure2.Suitable values can be found
from:

≅ 15V + V

V

pin 16

V

≅ V

CQ2

isthevoltageat thecollectorofQ2. V

(V

CQ2

pin 16

BEQ2

R9 + R8

.

+ VRsense

R8

CQ2

max
is 47V if thepin 8 isused forslow recirculationas in
fig. 2).

To ensurestability,a small capacitor(about200pF)
must beconnectedbetweenthe base andcollector
of Q2 when pin 16 is used.

A differentopportunityfor a fastoff timeis basedon
the use of the externalzener diodeDz. In this case
also themaximum Dz voltage valueis 47V.

LOAD DUMP PRO TE CTION

To protectthedeviceagainstthepositiveloaddump
it is necessaryto connect pin 1 to V

ishigherthan32V,the deviceturns offQ2and

if V

S

turnsonQ

. TheexternalresistorR6must be used

1

. In thiscase,

S

(see application circuit) to avoidthat pin 8 voltage
exceeds50V during loaddump. R

V

DUMP–V8

I

dp

where V

4.75V< V
ForthisR

R6>

is the dump voltage value and V8:

DUMP

<47V.

8

value,themini mumsupplyvoltageV

6

mustbe :

6

Smin

guaranteeingQ1 operationis givenby :

V

Smin

In relationto V

Ip



= R6



B

Q1



it isno moreverified Idp=35I

Smin

(+2)

V

BEQ1

R

5





+ V

8sat

ref

(typ) even if the system correct operation is com­pletelyguaranteed.

The L584 application circuit suggested in these
notesallowsthe useofinductiveloadswiththelow­estpossibleseriesresistance(compatiblewithcon­structionalrequirements)andthereforereducesno­tablythe powerdissipation.

For example, an electronic injector driven from

14.4Vwhich draws2.4A has a seriesresistanceof
6Ωanddissipates34.56W.Usingthiscircuita injec­torwith a 1Ω seriesresistancecanbe usedandthe
power dissipationis :

P

d=RLIL

whereR

2

+VDIL(1– σ)+V

= resistance of injector= 1Ω

L

V

=drop across diode,VD≅ 1V

D

V

= saturationvoltage of Q2, ≅ 1V

sat

R

= R11 = 185mΩ

S

⋅ ILσ +RSI

sat

2

σ

L

σ = duty cycle =20%
therefore:
Pd ≅ 5.76+1.92 + 0.48+ 0.21 = 8.37W
This given two advantages: the size (and cost) of

the injector is reduced and the drive current is re­ducedfrom2.4A to about0.4A.

Theapplicationcircuitoffigure9 isverysimilartofig­ure2 exceptthat itshows the use of two supplies:
onefor thecontrolcircuit,one forthe power stage.

10/13

Figure 9 : Applicationcircuitshowinghow two separatesuppliescan be used.

L584

In this applicationit is assumedthat the 5V supply
for L584 is taken from a logic supply, which is al­ready protected,againstload dump transientsand
vol-tagereversal.

Pin 1 must be left open, as shownin fig. 9, if V

L

alwayslowerthan46Vevenduringthe voltagetran-

R

sients.
Note that t

is alsorelated to the requiredcurrent

off

S

ripple∆I on the peak or on the holdingcurrent level
by :

t

=– ln

off

o

I

oRL+Voff

off

– ∆I) RL+V

(I

Where: Ioistheinitialcurrentvaluein OFFcondition
(equalto Ip or IHin accordanceto the currentlevel
considered),

V

OFF=VDIODE+VCEQ1

RLis the series resistance value of the induc­tanceL :

ThereforeC

canbe dimensioneddirectlyby :

2

Lln(Io–∆I)RL+V

I

C2=

REF

12 R

Notethatt

IoRL+V

L

isthe samefor boththepeakandhold-

off

OFF

OFF

ingcurrent.

is

t

timeis givenby :

on

LV

t

=ln

on

RV

– R(I1 – ∆I)

on

– RI1

on

where: I1 is the final current valuein ONcondition
(equalto I

or IHin accordanceto the current level

p

considered),

R=R

L+RSENSE

Von=VS–VCEsatQ2

If the constanttimes are respectively

LL

>20 t

RR

and > 20 t

off

it ispossibleto considera purelyinductiveloadand
therefore:

∆I ∆I

t

=L ;ton=L

off

V

o

V

on

on

11/13

L584

DIP16PACKAGE MECHANICAL DATA

DIM.

MIN. TYP. MAX. MIN. TYP. MAX.

a1 0.51 0.020

B 0.77 1.65 0.030 0.065
b 0.5 0.020

b1 0.25 0.010

D 20 0.787

E 8.5 0.335

e 2.54 0.100

e3 17.78 0.700

F 7.1 0.280

I 5.1 0.201

L 3.3 0.130
Z 1.27 0.050

mm inch

12/13

L584

Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for
the consequences 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 SGS-THOMSON Microelectronics. Specifica­tions mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information pre­viously supplied. SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or
systems without express written approval of SGS-THOMSON Microelectronics.

 1994 SGS-THOMSON Microelectronics - All Rights Reserved

Australia - Brazil - France - Germany - Hong Kong - Italy - Japan - Korea - Malaysia - Malta - Morocco - The Netherlands - Singapore-

SGS-THOMSON Microelectronics GROUP OF COMPANIES

Spain - Sweden - Switzerland - Taiwan - Thaliand - United Kingdom - U.S.A.

13/13