EL7551CU ELANTEC [Elantec Semiconductor], EL7551CU Datasheet - Page 3

• Manufacturer Part Number: EL7551CU
• Description: Monolithic 1 Amp DC:DC Step-down Regulator
• Manufacturer: ELANTEC [Elantec Semiconductor]

Pin Descriptions
Pin Number
10
12
13
14
15
16
11
1
2
3
4
5
6
7
8
9
Pin Name
VDRV
SGND
COSC
PGND
PGND
PGND
PGND
VREF
VDD
VIN
VIN
VHI
EN
LX
LX
FB
Control circuit negative supply.
Oscillator timing capacitor. FOSC can be approximated by: FOSC (kHz) = 0.1843/COSC, COSC in µF.
Control circuit positive supply.
Ground return of the regulator. Connected to the source of the low-side synchronous NMOS power FET.
Ground return of the regulator. Connected to the source of the low-side synchronous NMOS power FET.
Power supply input of the regulator. Connected to the drain of the high-side NMOS power FET.
Power supply input of the regulator. Connected to the drain of the high-side NMOS power FET.
Chip Enable, active high. A 2µA internal pull-up current enables the device if the pin is left open.
Ground return of the regulator.
Positive supply of the high-side driver.
Inductor drive pin. High current digital output whose average voltage equals the regulator output voltage.
Inductor drive pin. High current digital output whose average voltage equals the regulator output voltage.
Positive supply of the low-side driver and input voltage for the high-side boot strap.
Voltage feedback input. Connected to an external resistor divider between VOUT and GND. A 125nA pull-up current
forces VOUT to VS in the event that FB is floating.
Bandgap reference bypass capacitor. Typically 0.1µF to GND.
Ground return of the regulator.
Monolithic 1 Amp DC:DC Step-down Regulator
3
Pin Function
EL7551C