STMICROELECTRONICS L4909

L4909
EXTERNALLY ADJUSTABLE MULTIFUNCTION REGULATOR
■
3 OUTPUTS
- Vo1 : output voltage variable from 5 to 12 V;
limit current : 1.2 A.
- Vo2 : output voltage variable from 5 to 12 V;
limit current : 1.2 A.
- Vo3 : output voltage variable from 5 to 12 V;
limit current : 1.2 A.
■
ENABLE INPUT FOR EACH REGULATOR
■
FEEDBACK INPUT FOR EACH REGULATOR
■
SHORT CIRCUIT PROTECTION TO GROUND
■
OVERCURRENT WARNING
■
DRIVER FOR EXTERNAL SCR (CROWBAR
PROTECTION)
■
THERMAL SHUTDOWN
DESCRIPTION
It is a monolithic Multifunction Voltage Regulator; it
contains 3 regulators, (REG1, REG2, REG3) each
one with an enable input and a feedback input, to allow the voltage setting via external resistive divider.
MULTIWATT 15
Each regulator is current limited and furthermore an
OR-ed warning signal is output (open collector, active low output) when the current in a regulator goes
above an over-current threshold (1 A typ for any regulator).
When one output voltage is higher than 20% typ of its
nominal value (for instance in case of input-to-output
short circuit), the crowbar output pin is activated, triggering an external SCR (connected between input
and ground) that blows the input line fuse.
BLOCK DIAGRAM
REF
REFERENCE
GENERATOR
THERMAL
SHUTDOWN
EN1
EN2
EN3
+
REF+20%
3,13
VINA, VINB
+
6
REG1
7
REG1
ENABLE
CONTROL
9
REG2
REG3
+
+
+
2
-
1
+
VO1
FB1
+
OC
5
+
OVER
CURRENT
CHECK
REG2
14
-
-
15
+
TRIG
4
VO2
FB2
+
+
REG3
GND
8
+
11
10
VO3
FB3
D00AU1171
May 2000
1/7
L4909
PIN CONNECTION
15
FB2
14
VO2
13
VINB
12
N.C.
11
VO3
10
FB3
9
EN3
8
GND
7
EN2
6
EN1
5
OC
4
TRIG
3
VINA
2
VO1
1
FB1
TAB CONNECTED TO PIN 8
D00AU1153
Table 1. Pin Description
No. Pin
Name
1
FB1
REG1 feedback voltage input
2
Vo1
REG1 output voltage
3
VinA
Input DC supply voltage
4
TRIG
Trigger for external SCR (crowbar protection)
5
OC
Over current warning output
6
EN1
REG1 enable input
2/7
Function
7
EN2
REG2 enable input
8
GND
Analog ground
9
EN3
REG3 enable input
10
FB3
REG3 feedback voltage input
11
Vo3
REG3 output voltage
12
N.C.
Not Connected
13
VinB
Input DC supply voltage
14
Vo2
REG2 output voltage
15
FB2
REG2 feedback voltage input
L4909
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Vin
VinA,VinB input DC supply voltage
Io
Vo1, Vo2, Vo3 output currents
Value
Unit
40
V
internally limited
Voc
OC output voltage
min (15, Vin)
V
VENx
ENx input voltage
15
V
Top
Operating temperature range
Tstg
Storage temperature
0 to 70
o
C
- 40 to 150
oC
Value
Unit
1.8
°C/W
THERMAL DATA
Symbol
Parameter
RTH j-case
Thermal Resistance Junction to Case
ELECTRICAL CHARACTERISTICS (Cout = 100nF; Vin -Vo = 5V; Io = 10mA; Tcase = 25°C unless otherwise
specified
Symbol
Vo1
V(FB1)
Parameter
Test Condition
REG1 output voltage range
Min.
Typ.
5
Max.
Unit
12
V
1.32
V
REG1 feedback voltage
EN1=ON;
1.22
1.27
Ilim1
REG1 output current limit
EN1=ON; Vin-Vo1<12V
1.20
1.70
∆V o1
------------V o1
line regulation
Io1=10mA; Vin-Vo1=3 to 25 V
Io1=10mA; Vin-Vo1=3 to 12 V
0.6
0.1
2
%
∆V o1
------------V o1
load regulation
Io1=10 mA to 1.2A
Io1=10 mA to 0.5A
0.5
0.1
2
%
Vd1
REG1 drop out
Io1=500mA
2.20
V
SVR1
REG1 supply voltage rejec.
freq=120 Hz to 1KHz
Vo2
REG2 output voltage range
V(FB2)
A
60
dB
5
12
V
1.32
V
REG2 feedback voltage
EN2 = ON;
1.22
1.27
Ilim2
REG2 output current limit
EN2=ON; Vin-Vo2<12V
1.20
1.70
∆V o2
------------V o2
line regulation
Io2=10mA;Vin-Vo2=3 to 25 V
Io2=10mA;Vin-Vo2=3 to 12 V
0.6
0.1
2
%
∆V o2
------------V o2
load regulation
Io2=10 mA to 1.2A
Io2=10 mA to 0.5A
0.5
0.1
2
%
Vd2
REG2 drop out
Io2=500mA
2.2
V
A
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L4909
ELECTRICAL CHARACTERISTCS (continued)
Symbol
Parameter
SVR2
REG2 supply voltage rejec.
Vo3
REG3 output voltage range
V(FB3)
Test Condition
freq=120 Hz to 1KHz
Min.
Typ.
Max.
60
Unit
dB
5
12
V
1.32
V
REG3 feedback voltage
EN3=ON;
1.22
1.27
REG3 output current limit
EN3=ON; Vin-Vo3<12V
1.20
1.70
∆V o3
------------V o3
line regulation
Io3=10mA; Vin-Vo3=3 to 25 V
Io3=10mA; Vin-Vo3=3 to 12 V
0.6
0.1
2
%
∆V o3
------------V o3
load regulation
Io3=10 mA to 1.2A
Io3=10 mA to 0.5A
0.5
0.1
2
%
Vd3
REG3 drop out
Io3=500mA
2.20
V
REG3 supply voltage rejec.
freq=120 Hz to 1KHz
60
enable input voltage
(active high)
STAND_BY
ON
3.5
Istby
current consumption in stand_by
EN1=EN2=EN3≤0.5 V
ITRIG
current at TRIG output
SCR trigger circuit in ON state;
V(TRIG) = 2V
ZTRIG
TRIG to GND impedance
SCR trigger circuit in OFF state
0.2
KΩ
FBx voltage for trigger SCR on
any regulator
1.52
V
I(FB)
Feedback’s input current
any regulator
2
µA
I(EN)
EN’s input current
V(EN) = 5V
160
µA
current consumption in ON state
one regulator ON; Vo = 12V
two regulators ON; Vo = 12V
three regulators ON; Vo = 12V
11
20
29
mA
Ilim3
SVR3
ENx
V(FB)_TR
Ion
(current in the exter nal feedback resistors not
included)
V_OC_L current_warning output
voltage
warning conditions
Isink < 3 mA
I_OC_H
current_warning leakage
no warning conditions
V(OC) = 15V
I_oc/Ilim
warning threshold current / limit
current
any regulator
Vin - Vout <12V
4/7
A
dB
0.8
V
V
20
µA
25
mA
0.6
0.40
V
1
µA
L4909
The current protection is a function of the Vce, i.e. the drop between input and output voltages (Vin-Vo). The
shape of that relationship is shown in following figure 1.
Figure 1.
Figure 2. REGULATOR TYPICAL APPLICATION
ULTRAFAST FUSE
FROM
RECTIFIER
V INB
V INA
+5V
(*)EN1
6
3
13
2
(*)EN2
14
7
330nF
11
VO1
VO2
VO3
(*)EN3
4.7K
PULL-UP
RESISTOR
RB3
9
RB2
RB1
FB1
100µF
100nF
1
OC
FB2
5
100µF
100nF
15
FB3
SCR
100µF
100nF
12
TRIG
4
8
RA3
RA2
RA1
GND
D00AU1154
(*) It is possible to enable the regulators connecting the ENx pins to Vin through a 25KΩ
Suggested value for R Ax is 1.2KΩ
The value of RBx must be choosen, depending on the desired output voltage Vox? following the formula:
RBx = RAx
Vox
-1
1.27
5/7
L4909
mm
DIM.
MIN.
inch
A
MAX.
5
B
C
2.65
1.6
D
TYP.
MIN.
0.49
0.66
G
G1
1.02
17.53
H1
19.6
1.27
17.78
0.039
0.55
0.75
0.019
0.026
1.52
18.03
0.040
0.690
0.022
0.030
0.050
0.700
20.2
21.9
21.7
L2
17.65
L3
L4
17.25
10.3
L7
M
0.060
0.710
22.2
22.1
0.795
22.5
22.5
0.862
0.854
18.1
0.695
17.5
10.7
17.75
10.9
0.679
0.406
0.689
0.421
0.699
0.429
2.65
4.25
4.55
2.9
4.85
0.104
0.167
0.179
0.114
0.191
M1
4.63
5.08
5.53
0.182
0.200
S
S1
1.9
1.9
2.6
2.6
0.075
0.075
0.102
0.102
Dia1
3.65
3.85
0.144
0.152
6/7
OUTLINE AND
MECHANICAL DATA
0.772
H2
L
L1
MAX.
0.197
0.104
0.063
1
E
F
TYP.
0.874
0.870
0.886
0.886
0.713
0.218
Multiwatt15 V
L4909
Information furnished is believed to be accurate and reliable. However, STMicroelectronics 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. N o 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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