L4973V3 - L4973V5 - L4973D3 - L4973D5
THERMAL DATA
Symbol
R
th(j-pin)
R
th(j-amb)
Parameter
Thermal Resistance Junction to pin
Thermal Resistance to Ambient
Max.
Max.
Powerdip
12
60 (*)
SO20
15
80 (*)
Unit
°C/W
°C/W
(*) Package mounted on board.
ABSOLUTE MAXIMUM RATINGS
Symbol
DIP-18
V
7
,V
8
V
2
,V
3
I
2
,I
3
V
9
-V
8
V
9
V
11
V
17
V
12
V
18
V
10
P
tot
S0-20
V
9
,V
8
V
2
,V
3
I
2
,I
3
V
10
-V
8
V
10
V
12
V19
V
13
V
20
V
11
Bootstrap voltage
Analogs input voltage (V
CC
= 24V)
Analogs input voltage (V
CC
= 24V)
(V
CC
= 20V)
(V
CC
= 20V)
Inhibit
Power dissipation a T
pins
≤
90°C
(T
amb
= 70°C no copper area)
(T
amb
= 70°C 4cm copper area on PCB)
Power dissipation a T
pins
= 90°C
T
J
,T
STG
Junction and storage temperature
DIP
12+3+3
SO20
Input voltage
Output DC voltage
Output peak voltage at t = 0.1µs f=200KHz
Maximum output current
Parameter
Value
58
-1
-5
int. limit.
14
70
12
13
6
-0.3
5.5
-0.3
Vcc
-0.3
5
1.3
2
4
-40 to 150
V
V
V
V
V
V
V
V
V
V
W
W
W
W
°C
Unit
V
V
V
PIN FUNCTIONS
Powerdip
11
10
9
18
7,8
2,3
12
SO20
12
11
10
20
8,9
2,3
13
NAME
COMP
INH
BOOT
SYNC
Vcc
OUT
VFB
DESCRIPTION
E/A output to be used for frequency compensation
A logic signal (active high) disables the device (sleep mode operation).
If not used it must be connected to GND; if floating the device is disabled.
A capacitor connected between this pin and the output allows to drive the
internal D-MOS.
Input/Output synchronization.
Unregulated DC input voltage
Stepdown regulator output.
Stepdown feedback input. Connecting the output directly to this pin results
in an output voltage of 3.3V for the L4973V3.3 and 5.1V. An external
resistive divider is required for higher output voltages. For output voltage
less than 3.3V, see note ** and Figure 32.
Reference voltage externally available.
Signal ground
An external resistor connected between the unregulated input voltage and
Pin 1 and a capacitor connected from Pin 1 to ground fixes the switching
frequency. (Line feed forward is automatically obtained)
16
4,5,6
13,14,15
1
18
4,5,6,7
14,15,16,17
1
V5.1
GND
OSC
3/16
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