el7551 Intersil Corporation, el7551 Datasheet - Page 3

• Manufacturer Part Number: el7551
• Description: Monolithic 1amp Dc Dc Step-down Regulator
• Manufacturer: Intersil Corporation

Pin Descriptions
Closed-Loop AC Electrical Specifications
F
t
M
t
t
D
SYNC
BRM
LEB
PARAMETER
NUMBER
OSC
MAX
SS
PIN
10
11
12
13
14
15
16
1
2
3
4
5
6
7
8
9
PIN NAME
SGND
COSC
PGND
PGND
PGND
PGND
VDRV
VREF
VDD
Oscillator Initial Accuracy
Minimum Oscillator Sync Width
Soft Start Slope
FET Break Before Make Delay
High Side FET Minimum On Time
Maximum Duty Cycle
VIN
VIN
VHI
EN
FB
LX
LX
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.
DESCRIPTION
3
V
S
= V
EL7551
IN
= 5V, T
CONDITIONS
A
PIN FUNCTION
= T
J
= 25°C, C
OSC
= 1.2nF, unless otherwise specified.
MIN
105
TYP
117
150
0.5
25
15
95
MAX
130
UNIT
V/ms
kHz
ns
ns
ns
%