L4971 STMicroelectronics, L4971 Datasheet - Page 2
L4971
Manufacturer Part Number
L4971
Description
IC REG SW 1.5A STEP DOWN 8-DIP
Manufacturer
STMicroelectronics
Type
Step-Down (Buck)r
Datasheet
1.L4971D013TR.pdf
(13 pages)
Specifications of L4971
Internal Switch(s)
Yes
Synchronous Rectifier
No
Number Of Outputs
1
Voltage - Output
3.3 ~ 50 V
Current - Output
1.5A
Frequency - Switching
100kHz ~ 300kHz
Voltage - Input
8 ~ 55 V
Operating Temperature
0°C ~ 125°C
Mounting Type
Through Hole
Package / Case
8-DIP (0.300", 7.62mm)
Power - Output
1W
Output Voltage
50 V
Mounting Style
Through Hole
For Use With
497-4744 - BOARD EVAL FOR L4971/L4978 REG
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Other names
497-6697-5
E-L4971
E-L4971
L4971
E-L4971
E-L4971
L4971
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
L4971
Manufacturer:
ST
Quantity:
20 000
Part Number:
L49710MA
Manufacturer:
NS/国半
Quantity:
20 000
Company:
Part Number:
L4971AD013TR
Manufacturer:
MIT
Quantity:
6 231
Part Number:
L4971D013TR
Manufacturer:
SOP16
Quantity:
20 000
L4971
Figure 2. Block Diagram
Figure 3. Pin Connections
Table 2. Pin Description
(*) Pins 1, 7, 8, 9, 10, 15 and 16 are not internally, electrically connected to the die.
2/13
DIP
1
2
3
4
5
6
7
8
SS_INH
COMP
SO (*)
5, 6
11
12
13
14
SS_INH
FB
2
3
4
GND
OSC
OUT
3.3V
2
7
8
SS_INH
COMP
BOOT
Name
GND
OSC
OUT
V
SHUTDOWN
INHIBIT
FB
THERMAL
CC
1
2
3
4
OSCILLATOR
E/A
DIP8
D97IN595
OSC
Ground
A logic signal (active low) disables the device (sleep mode operation).
A capacitor connected between this pin and ground determines the soft start time.
When this pin is grounded disabled the device (driven by open collector/drain).
An external resistor connected between the unregulated input voltage and this pin and
a capacitor connected from this pin to ground fix the switching frequency. (Line feed
forward is automatically obtained)
Stepdown regulator output
Unregulated DC input voltage
A capacitor connected between this pin and OUT allows to drive the internal DMOS
Transistor
E/A output to be used for frequency compensation
Stepdown feedback input. Connecting directly to this pin results in an output voltage of
3.3V. An external resistive divider is required for higher output voltages.
3
SOFTSTART
8
7
6
5
PWM
VOLTAGES
MONITOR
FB
COMP
BOOT
VCC
3.3V
REFERENCE
INTERNAL
R
S
GND
1
Q
SS_INH
GND
OSC
OUT
OUT
N.C.
N.C.
N.C.
INTERNAL
SUPPLY
Function
1
2
3
4
5
6
7
8
DRIVE
5.1V
D97IN596
SO16
5
VCC
OUT
4
16
15
14
13
12
11
10
9
AT LIGHT
CHARGE
CHARGE
CBOOT
CBOOT
LOADS
D97IN594
N.C.
N.C.
FB
COMP
BOOT
VCC
N.C.
N.C.
6
BOOT