E-L4978D STMicroelectronics, E-L4978D Datasheet - Page 2

• Manufacturer Part Number: E-L4978D
• Description: IC REG SW 2A STEP DOWN 16-SOIC
• Manufacturer: STMicroelectronics
• Type: Step-Down (Buck)r

Specifications of E-L4978D

• Internal Switch(s): Yes
• Synchronous Rectifier: No
• Number Of Outputs: 1
• Voltage - Output: 3.3 ~ 50 V
• Current - Output: 2A
• Frequency - Switching: 100kHz ~ 300kHz
• Voltage - Input: 8 ~ 55 V
• Operating Temperature: -40°C ~ 150°C
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (0.300", 7.5mm Width)
• Power - Output: 800mW
• Output Voltage: 3.5 V
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

L4978
Table 2. Block Diagram
Figure 3. Pins Connection (Top view)
Table 3. Pin Description
2/13
N°
1
2
3
SS_INH
SS_INH
COMP
GND
FB
OSC
OUT
Pin
3.3V
2
3
4
2
7
8
SHUTDOWN
INHIBIT
THERMAL
1
2
3
4
OSCILLATOR
SS_INH
E/A
Name
GND
OSC
DIP-8
D97IN595
OSC
3
SOFTSTART
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 disables 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)
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
SO16W
5
VCC
OUT
4
AT LIGHT
CHARGE
CHARGE
CBOOT
CBOOT
16
15
14
13
12
11
10
LOADS
9
D97IN594
6
N.C.
N.C.
FB
COMP
BOOT
VCC
N.C.
N.C.
BOOT