L4981A
L4981B
POWER FACTOR CORRECTOR
CONTROL BOOST PWM UP TO 0.99P.F.
LIMIT LINE CURRENT DISTORTION TO < 5%
UNIVERSAL INPUT MAINS
FEED FORWARD LINE AND LOAD REGULA-
TION
AVERAGE CURRENT MODE PWM FOR
MINIMUM NOISE SENSITIVITY
HIGH CURRENT BIPOLAR AND DMOS TO-
TEM POLE OUTPUT
LOW START-UP CURRENT (0.3mA TYP.)
UNDER VOLTAGE LOCKOUT WITH HYS-
TERESIS AND PROGRAMMABLE TURN ON
THRESHOLD
OVERVOLTAGE, OVERCURRENT PROTEC-
TION
PRECISE 2% ON CHIP REFERENCE EX-
TERNALLY AVAILABLE
SOFT START
DESCRIPTION
The L4981 I.C. provides the necessary features
to achieve a very high power factor up to 0.99.
Realized in BCD 60II technology this power factor
corrector (PFC) pre-regulator contains all the con-
trol functions for designing a high efficiency-mode
power supply with sinusoidal line current con-
sumption.
The L4981 can be easily used in systems with
mains voltages between 85V to 265V without any
line switch. This new PFC offers the possibility to
work at fixed frequency (L4981A) or modulated
frequency (L4981B) optimizing the size of the in-
November 2001
BLOCK DIAGRAM
ORDERING NUMBERS: L4981X (DIP20)
L4981XD (SO20)
DIP20
SO20
MULTIPOWER BCD TECHNOLOGY
1/16
put filter; both the operating frequency modes
working with an average current mode PWM con-
troller, maintaining sinusoidal line current without
slope compensation.
Besides power MOSFET gate driver, precise volt-
age reference (externally available), error ampli-
fier, undervoltage lockout, current sense and the
soft start are included. To limit the number of the
external components, the device integrates pro-
tections as overvoltage and overcurrent. The
overcurrent level can be programmed using a
simple resistor for L4981A. For a better precision
and for L4981B an external divider must be used.
ABSOLUTE MAXIMUM RATINGS
Symbol
Pin
Parameter
Value
Unit
V
CC
19
Supply Voltage (I
CC
50mA) (*)
selflimit
V
I
GDRV
20
Gate driv. output peak current (t = 1
s) SINK
2
.
SOURCE
1.5
A
V
GDRV
Gate driv. output voltage t = 0.1
s
-1
V
Voltages at pins 3, 14, 7, 6, 12, 15
-0.3 to 9
V
V
VA-OUT
13
Error Amplifier Voltage
-0.3 to 8.5
V
I
AC
4
AC Input Current
5
mA
Voltages at pin 8, 9
-0.5 to 7
V
V
CA-OUT
5
Current Amplifier Volt. (Isource = -20mA; Isink = 20mA)
-0.3 to 8.5
V
V
ROSC
17
Voltage at pin 17
-0.3 to 3
V
11, 18
Voltage at pin 11, 18
-0.3 to 7
V
I
COSC
18
Input Sink Current
15
mA
I
FREQ-MOD
16
Frequency Modulation Sink Current (L4981B)
5
mA
V
SYNC
16
Sync. Voltage (L4981A)
-0.3 to 7
V
V
IPK
2
Voltage at pin 2
Voltage at Pin 2 t = 1
s
-0.3 to 5.5
-2
V
V
P
tot
Power Dissipation at T
amb
= 70
C (DIP20)
1
W
Power Dissipation at T
amb
= 70
C (SO20)
0.6
W
T
op
Operating Ambient Temperature
-40 to 125
C
T
stg
StorageTemperature
-55 to 150
C
(*) Maximum package power dissipation limits must be observed.
PIN CONNECTIONS (Top views)
L4981A
L4981B
L4981A - L4981B
2/16
THERMAL DATA
Symbol
Parameter
DIP 20
SO 20
Unit
R
th j-amb
Thermal Resistance Junction-ambient
80
120
C/W
PIN FUNCTIONS
N.
Name
Description
1
P-GND
Power ground.
2
IPK
L4981A peak current limiting. A current limitation is obtained using a single resistor connected
between Pin 2 and the sense resistor. To have a better precision another resistor between Pin
2 and a reference voltage (Pin 11) must be added.
L4981B peak current limiting. A precise current limitation is obtained using two external
resistor only. These resistors must be connected between the sense resistor, Pin 2 and the
reference voltage.
3
OVP
Overvoltage protection. At this input are compared an internal precise 5.1V (typ) voltage
reference with a sample of the boost output voltage obtained via a resistive voltage divider in
order to limit the maximum output peak voltage.
4
IAC
Input for the AC current. An input current proportional to the rectified mains voltage generates,
via a multiplier, the current reference for the current amplifier.
5
CA-OUT
Current amplifier output. An external RC network determinates the loop gain.
6
LFF
Load feedforward; this voltage input pin allows to modify the multiplier output current
proportionally to the load, in order to give a faster response versus load transient. The best
control is obtained working between 1.5V and 5.3V. If this function is not used, connect this pin
to the voltage reference (pin = 11).
7
VRMS
Input for proportional RMS line voltage. the VRMS input compesates the line voltage changes.
Connecting a low pass filter between the rectified line and the pin 7, a DC voltage proportional
to the input line RMS voltage is obtained. The best control is reached using input voltage
between 1.5V and 5.5V. If this function is not used connect this pin to the voltage reference
(pin = 11).
8
MULT-OUT
Multiplier output. This pin common to the multiplier output and the current amplifier N.I. input is
an high impedence input like I
SENSE
. The MULT-OUT pin must be taken not below -0.5V.
9
I
SENSE
Current amplifier inverting input. Care must be taken to avoid this pin goes down -0.5V.
10
S-GND
Signal ground.
11
V
REF
Output reference voltage (typ = 5.1V).Voltage refence at
2% of accuracy externally available,
it's internally current limited and can deliver an output current up to 10mA.
12
SS
A capacitor connected to ground defines the soft start time. An internal current generator
delivering 100
A (typ) charges the external capacitor defining the soft start time constant. An
internal MOS discharge, the external soft start capacitor both in overvoltage and UVLO
conditions.
13
VA-OUT
Error amplifier output, an RC network fixes the voltage loop gain characteristics.
14
VFEED
Voltage error amplifier inverting input. This feedback input is connected via a voltage divider to
the boost output voltage.
15
P-UVLO
Programmable under voltage lock out threshold input. A voltage divider between supply
voltage and GND can be connected in order to program the turn on threshold.
16
SYNC
(L4981A)
This synchronization input/output pin is CMOS logic compatible. Operating as SYNC in, a
rectangular wave must be applied at this pin. Opearting as SYNC out, a rectangular clock
pulse train is available to synchronize other devices.
FREQ-MOD
(L4981B)
Frequency modulation current input. An external resistor must be connected between pin 16
and the rectified line voltage in order to modulate the oscillator frequency. Connecting pin 16 to
ground a fixed frequency imposed by R
OSC
and C
OSC
is obtained.
17
R
OSC
An external resistor connected to ground fixes the constant charging current of C
OSC
.
18
C
OSC
An external capacitor connected to GND fixes the switching frequency.
19
V
CC
Supply input voltage.
20
GDRV
Output gate driver. Bipolar and DMOS transistors totem pole output stage can deliver peak
current in excess 1A useful to drive MOSFET or IGBT power stages.
L4981A - L4981B
3/16
ELECTRICAL CHARACTERISTICS (Unless otherwise specified V
CC
= 18V, C
OSC
= 1nF,
R
OSC
= 24K
, C
SS
= 1
F, V
CA-OUT
= 3.5V, V
ISENSE
= 0V, V
LFF
= V
REF
, I
AC
= 100
A, V
RMS
= 1V,
V
FEED
= GND, V
IPK
= 1V, V
OVP
= 1V, T
J
= 25
C
Symbol
Prameter
Test Condition
Min.
Typ.
Max.
Unit
ERROR AMPLIFIER SECTION
V
IO
Input Offset Voltage
25
C < T
J
< 85
C
8
mV
I
IB
Input Bias Current
V
FEED
= 0V
-500
-50
500
nA
Open Loop Gain
70
100
dB
V
13H
Output High voltage
V
FEED
= 4.7V
I
VA-OUT
= -0.5mA
5.5
6.5
7.5
V
V
13L
Output Low Voltage
V
FEED
= 5.5V
I
VA-OUT
= 0.5mA
0.4
1
V
-I
13
Output Source Current
V
FEED
= 4.7V; V
VA-OUT
= 3.5V
2
10
mA
I
13
Output Sink Current
V
FEED
= 5.5V; V
VA-OUT
= 3.5V
4
20
mA
REFERENCE SECTION
V
ref
Reference Output Voltage
25
C < T
J
< 85
C
4.97
5.1
5.23
V
T
j
= 25
C I
ref
= 0
5.01
5.1
5.19
V
V
ref
Load Regulation
1mA
I
ref
10mA
25
C < T
J
< 85
C
3
15
mV
V
ref
Line Regulation
12V
V
CC
19V
25
C < T
J
< 85
C
3
10
mV
I
ref sc
Short Circuit Current
V
ref
= 0V
20
30
50
mA
OSCILLATOR SECTION
f
osc
Initial Accuracy
T
j
= 25
C
85
100
115
KHz
Frequency Stability
12V
V
CC
19V
25
C < T
J
< 85
C
80
100
120
KHz
V
svp
Ramp Valley to Peak
4.7
5
5.3
V
I
18C
Charge Current
V
COSC
= 3.5V
0.45
0.55
0.65
mA
I
18D
Discharge Current
V
COSC
= 3.5V
11.5
mA
V
18
Ramp Valley Voltage
0.9
1.15
1.4
V
SYNC SECTION (Only for L4981A)
t
W
Output Pulse Width
50% Amplitude
0.3
0.8
s
I
16
Sink Current with Low Output
Voltage
V
SYNC
= 0.4V
V
COSC
= 0V
0.4
0.8
mA
-I
16
Source Current with High Output
Voltage
V
SYNC
= 4.5V
V
COSC
= 6.7V
1
6
mA
V
16L
Low Input Voltage
0.9
V
V
16H
High Input Voltage
3.5
V
t
d
Pulse for Synchronization
800
ns
FREQUENCY MODULATION FUNCTION (Only for L4981B)
f
18max
Maximum Oscillation Frequency
V
FREQ-MOD
= 0V (Pin 16) I
freq
= 0
85
100
115
KHz
f
18min
Minimum Oscillator Frequency
I
FREQ-MOD
= 360
A (Pin 16)
V
VRMS
= 4V (Pin 7)
74
KHz
I
FREQ-MOD
= 180
A (Pin 16)
V
VRMS
= 2V (Pin 7)
76
KHz
SOFT START SECTION
I
SS
Soft Start Source Current
V
SS
= 3V
60
100
140
A
V
12sat
Output Saturation Voltage
V
3
= 6V, I
SS
= 2mA
0.1
0.25
V
L4981A - L4981B
4/16
ELECTRICAL CHARACTERISTICS (continued)
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
SUPPLY VOLTAGE
V
CC
Operating Supply Voltage
19.5
V
OVER VOLTAGE PROTECTION COMPARATOR
V
thr
Rising Threshold Voltage
V
ref
-20mV
5.1
V
ref
+20mV
V
V
3Hys
Hysteresis
180
250
320
mV
I
3
Input Bias Current
0.05
1
A
t
d
Propagation delay to output
V
OVP
= V
thr
+100mV
1
2
s
OVER CURRENT PROTECTION COMPARATOR
V
th
Threshold Voltage
30
mV
t
d
Propagation delay to Output
V
OCP
= V
thr
-0.2V
0.4
0.9
s
I
ipk
Current Source Generator
V
IPK
= -0.1V only for L4981A
65
85
105
A
I
L
Leakage Current
V
IPK
= -0.1V only for L4981B
5
A
CURRENT AMPLIFIER SECTION
V
offset
Input Offset Voltage
V
MULT OUT
= V
SENSE
= 3.5V
2
mV
I
9bias
Input Bias Current
V
SENSE
= 0V
-500
50
500
nA
Open Loop Gain
1.1V
V
CA OUT
6V
70
100
dB
SVR
Supply Voltage Rejection
12V
V
CC
19V
V
MULT OUT
= 3.5V V
SENSE
= 3.5V
68
90
dB
V
5H
Output High Voltage
V
MULT OUT
= 200mV
I
CA OUT
= -0.5mA, V
IAC
= 0V
6.2
V
V
5L
Output Low Voltage
V
MULT OUT
= -200mV
I
CA OUT
= 0.5mA, V
IAC
= 0V
0.9
V
-I
5
Output Source Current
V
MULT OUT
= 200mV,
V
IAC
= 0V, V
CA-OUT
= 3.5V
2
10
mA
I
5
Output Sink Current
2
10
mA
OUTPUT SECTION
V
20L
Output Voltage Low
I
SINK
= 250mA
0.5
0.8
V
V
20H
Output Voltage High
I
SOURCE
= 250mA
V
CC
= 15V
11.5
12.5
V
t
r
Output Voltage Rise Time
C
OUT
= 1nF
50
150
ns
t
f
Output Voltage Fall Time
C
OUT
= 1nF
30
100
ns
V
GDRV
Voltage Clamp
I
SOURCE
= 0mA
13
16
19
V
TOTAL STANDBY CURRENT SECTION
I
19start
Supply Current before start up
V
CC
= 14V
0.3
0.5
mA
I
19on
Supply Current after turn on
V
IAC
= 0V, V
COSC
= 0,
Pin17 = Open
8
12
mA
I
19
Operating Supply Current
Pin20 = 1nF
12
16
mA
V
CC
Zener
Voltage
(*)
20
25
30
V
UNDER VOLTAGE LOCKOUT SECTION
V
th ON
Turn on Threshold
14.5
15.5
16.5
V
V
th OFF
Turn off Threshold
9
10
11
V
Programmable Turn-on Threshold
Pin 15 to V
CC
= 220K
Pin15 to GND = 33K
10.6
12
13.4
V
LOAD FEED FORWARD
I
LFF
Bias Current
V
6
= 1.6V
70
140
A
V
6
= 5.3V
200
300
A
V
I
Input Voltage Range
1.6
5.3
V
(*) Maximum package power dissipation limits must be observed.
L4981A - L4981B
5/16
ELECTRICAL CHARACTERISTICS (continued)
Symbol
Prameter
Test Condition
Min.
Typ.
Max.
Unit
MULTIPLIER SECTION
Multipler Output Current
V
VA-OUT
= 4V, V
RMS
= 2V,
V
MULTOUT
= 0, V
LFF
= 5.1V
I
AC
= 50
A, C
OSC
= 0V
20
35
52
A
V
VA-OUT
= 4V, V
RMS
= 2V,
V
MULTOUT
= 0, V
LFF
= 5.1V
I
AC
= 200
A, C
OSC
= 0V
100
135
170
A
V
VA-OUT
= 2V, V
RMS
= 2V,
V
MULTOUT
= 0, V
LFF
= 5.1V
I
AC
= 100
A, C
OSC
= 0V
10
20
30
A
V
VA-OUT
= 2V, V
RMS
= 4V,
V
MULTOUT
= 0, V
LFF
= 5.1V
I
AC
= 100
A, C
OSC
= 0V
2
5.5
11
A
V
VA-OUT
= 4V, V
RMS
= 4V,
V
MULTOUT
= 0, V
LFF
= 5.1V
I
AC
= 100
A, C
OSC
= 0V
10
22
34
A
V
VA-OUT
= 4V, V
RMS
= 2V,
V
MULTOUT
= 0, V
LFF
= 2.5V
C
OSC
= 0V, I
AC
= 200
A
20
37
54
A
V
VA-OUT
= 4V, V
RMS
= 4V
V
MULTOUT
= 0, V
LFF
= 5.1V
I
AC
= 200
A, C
OSC
= 0V
20
39
54
A
V
VA-OUT
= 2V, V
RMS
= 4V,
V
MULTOUT
= 0, V
LFF
= 5.1V
I
AC
= 0, C
OSC
= 0V
-2
0
2
A
K
Multiplier Gain
0.37
I
MULT
-
OUT
=
K
I
AC
(
V
VA
-
OUT
-
1.28
)
(
0.8
V
LFF
-
1.28
)
(
V
VRMS
)
2
if V
LFF
= V
REF; I
MULT
-
OUT
=
I
AC
(
V
VA
-
OUT
-
1.28
)
(
V
VRMS
)
2
K1
where: K1 = 1V
Figure 1: MULTI-OUT vs. I
AC
(V
RMS
= 1.7V;
V
LFFD
= 5.1V)
Figure 2: MULTI-OUT vs. I
AC
(V
RMS
= 2.2V;
V
LFFD
= 5.1V)
L4981A - L4981B
6/16
Figure 3: MULTI-OUT vs. I
AC
(V
RMS
= 4.4V;
V
LFFD
= 5.1V)
Figure 4: MULTI-OUT vs. I
AC
(V
RMS
= 5.3V;
V
LFFD
= 5.1V)
Figure 6: MULTI-OUT vs. I
AC
(V
RMS
= 2.2V;
V
LFFD
= 2.5V)
Figure 5: MULTI-OUT vs. I
AC
(V
RMS
= 1.7V;
V
LFFD
= 2.5V)
Figure 7: MULTI-OUT vs. I
AC
(V
RMS
= 4.4V;
V
LFFD
= 2.5V)
Figure 8: MULTI-OUT vs. I
AC
(V
RMS
= 5.3V;
V
LFFD
= 2.5V)
L4981A - L4981B
7/16
C7
220nF
100V
R17
806K
1%
R17
806K
1%
R22
R23
R19
1.1M
5%
R19
1.1M
5%
R8
33K
5%
R7 360K 5% R6 620K 5%
R6
620K
5%
4
7
BRIDGE
4 x BY214
C1
220nF
400V
R21
5.1K
1%
L4981A
2
R15
10K
0.5W
R14
56
0.5W
C10
15nF
100V
19
15
D4
1N4150
DZ
22V
0.5W
C11
100
F
25V
D3 1N4150
D3
2N2222
C8
220nF
100V
L 0.9mH
14
13
C9
330nF
R12
220K
5%
3
C12
270pF
630V
STH/STW15NB50
R13
Q1
Q2
STK2N50
D5
BYT
11600
R18
1.8K
4W
20
R11
560 1%
R3
2.7K
5%
R5
27K 5%
0.07 2W
C3
1nF
R4
2.7K
5%
R16
24K
1%
15 5%
C4
1nF
C6
1
F
16V
6
1
R2
11K
1%
R10
21K
1%
R1
412K
1%
R9
910K
1%
R1
412K
1%
R9
910K
1%
D1 5TTA5060
12
C5
1
F
16V
11
17
18
9
5
8
FUSE
C2
100
F
450V
+
-
Vo
D93IN029C
Vi
88VAC to 254VAC
NTC
D2 1N4150
R
S
R20
10K 5%
Figure 9A: L4981A Power Factor Corrector (200W)
f
SW
= 80kHz; P
O
= 200W; V
OUT
= 400V; I
rms max
= 2.53A; V
OVP
= 442V; I
PK max
= 6.2A
C7
220nF
100V
R17
806K
1%
R22
1.1M
R17
806K
1%
R22
R23
R19
1.1M
5%
R19
1.1M
5%
R8
33K
5%
R7 360K 5% R6 620K 5%
R6
620K
5%
4
16
7
BRIDGE
4 x BY214
C1
220nF
400V
R21
5.1K
1%
L4981B
2
R15
10K
0.5W
R14
56
0.5W
C10
15nF
100V
19
15
D4
1N4150
DZ
22V
0.5W
C11
100
F
25V
D3 1N4150
D3
2N2222
C8
220nF
100V
L 0.9mH
14
13
C9
330nF
R12
220K
5%
3
C12
270pF
630V
STH/STW15NB50
R13
Q1
Q2
STK2N50
D5
BYT
11600
R18
1.8K
4W
20
R11
560 1%
R3
2.7K
5%
R5
27K 5%
0.07 2W
C3
1nF
R4
2.7K
5%
R16
24K
1%
15 5%
C4
1.1nF
C6
1
F
16V
6
1
R2
11K
1%
R10
21K
1%
R1
412K
1%
R9
910K
1%
R1
412K
1%
R9
910K
1%
D1 5TTA5060
12
C5
1
F
16V
11
17
18
9
5
8
FUSE
C2
100
F
450V
+
-
Vo
D95IN220A
Vi
88VAC to 254VAC
NTC
D2 1N4150
R
S
R20
10K 5%
Figure 9B: L4981B Power Factor Corrector (200W)
f
SW
= 80 to 92kHz; P
O
= 200W; V
OUT
= 400V; I
rms max
= 2.53A; V
OVP
= 442V; I
PK max
= 6.2A
L4981A - L4981B
8/16
Figure 10: Reference Voltage vs. Source Refer-
ence Current
Figure 12: Reference Voltage vs. Junction Tem-
perature
Figure 14: Gate Driver Rise and Fall Time
Figure 11: Reference Voltage vs. Supply Voltage
Figure 13: Switching Frequency vs. Junction
Temperature
Figure 15: Operating Supply Current vs. Supply
Voltage
L4981A - L4981B
9/16
Figure 16: Programmable Under Voltage Lock-
out Thresholds
Table 1: Programmable Under Voltage Lockout Thresholds.
V
CC
ON
V
CC
OFF
R22
R23
11V
10V
82k
12k
12V
10.1V
220k
33k
13V
10.5V
430k
62k
14V
10.8V
909k
133k
14.5V
10.9V
1.36M
200k
15V
11V
2.7M
390k
Vl
0.8
1
0.4
0.2
0
0
45
90
135
Electrical degrees
180
0.8
1
0.4
0.2
0
fsw
Figure 17: Modulation Frequency Normalized in
an Half Cycle of the Mains Voltage
Figure 18: Oscillator Diagram
R22 = R23
6.8
R23 (Kohm)
L4981A - L4981B
10/16
88 to 264 Vac
BRIDGE
B1 8A
L1=0.5mE42*21*15
gap=1.9 58/6 turns
20*.2mm
C2
330n
C3
330n
R2
33k
R5
220k
R4
1.2M
R6
500k
7
4
C1
330nF
400V
L4981A/ B**
15
16
R7
500k
19
C8
100n
13
R1
460
R3
2.2k
R8
17k
C6
3.3n
R13
2.2k
C9
1n
R15
24k
1
17
10
18
9
5
8
2
R9 (RS)
50m
// 3*0.15)
R10
5k
R11
56k
R12
56k
R16
220k
14
3
C14
100n
R17
15
# // Q1&Q2
TO220*2
STM12NM50
/ 7C/W
D7-STTA406
20
C12
1u
C13
1u
R21
19.6k
R24
16.9k
R19
750k
R22
750k
D4-STTH8R06
to220 (/40CW)
6
11
12
C15
220uF
450V
-
D3
L2
3u
R18
6.8
2W
R23
750k
C11
220n
R20
750k
R14
68
B2= D1+D2
+D8+D9
VCC
F1
T15A250V
NTC
2.5
V+ BUS=400V
D5-
STTA106
D6
DZW06-48
RAux1
RAux2
Cf
.22uF
600V
TP1
VCC
C10
150uF
Dz1
18V
Q4
4007
R25
1k
2W
Cs
330pF
Q1+Q2#
**
Figure 19: Demo Board Circuit (V
O
= 400V; P
O
= 360W).
Figure 20: Component Layout (Dimensions 88 x 150mm).
L4981A - L4981B
11/16
Figure 20: P.C.B. Component Side (Dimensions 88 x 150mm).
Figure 20: P.C.B. Solder Side (Dimensions 88 x 150mm).
L4981A - L4981B
12/16
DEMO BOARD EVALUATION RESULTS
Table 2. Nominal Power range at 110Vac.
V
mains
P
out
V
out
P
in
THD
PF
Eff.
88Vac
366W
404Vdc
397W
5%
0.998
.92
110Vac
370W
406Vdc
395W
2.2%
0.999
.94
132Vac
372W
407Vdc
394W
3%
0.999
.945
Table 3. Nominal Power range at 220Vac.
V
mains
P
out
V
out
P
in
THD
PF
Eff.
176Vac
378W
410Vdc
394W
4.7%
0.997
.959
220Vac
381W
412Vdc
395W
6.4%
0.993
.964
264Vac
381W
412Vdc
395W
8.1%
0.987
.964
REFERENCE:
AN628 - DESIGNING A HIGH POWER FACTOR SWITCHING PREREGULATOR WITH THE L4981
CONTINUOUS MODE
L4981A - L4981B
13/16
1
1
0
11
20
A
e
B
D
E
L
K
H
A1
C
SO20MEC
h x 45
SO20
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
2.35
2.65
0.093
0.104
A1
0.1
0.3
0.004
0.012
B
0.33
0.51
0.013
0.020
C
0.23
0.32
0.009
0.013
D
12.6
13
0.496
0.512
E
7.4
7.6
0.291
0.299
e
1.27
0.050
H
10
10.65
0.394
0.419
h
0.25
0.75
0.010
0.030
L
0.4
1.27
0.016
0.050
K
0 (min.)8 (max.)
OUTLINE AND
MECHANICAL DATA
L4981A - L4981B
14/16
DIP20
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
a1
0.254
0.010
B
1.39
1.65
0.055
0.065
b
0.45
0.018
b1
0.25
0.010
D
25.4
1.000
E
8.5
0.335
e
2.54
0.100
e3
22.86
0.900
F
7.1
0.280
I
3.93
0.155
L
3.3
0.130
Z
1.34
0.053
OUTLINE AND
MECHANICAL DATA
L4981A - L4981B
15/16
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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. Specification 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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L4981A - L4981B
16/16
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