MAX5080ATE Maxim Integrated Products, MAX5080ATE Datasheet - Page 10

• Manufacturer Part Number: MAX5080ATE
• Description: DC/DC Switching Converters
• Manufacturer: Maxim Integrated Products

Specifications of MAX5080ATE

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

SS is the 1.23V reference bypass connection for the
MAX5080/MAX5081 and also controls the soft-start
period. At startup, after V
and external UVLO thresholds are reached, the device
enters soft-start. During soft-start, 15µA is sourced into
the capacitor (C
ing the reference voltage to ramp up slowly. When V
reaches 1.23V the output becomes fully active. Set the
soft-start time (t
where t
1A, 40V, MAXPower Step-Down
DC-DC Converters
Figure 2. MAX5081 Simplified Block Diagram
10
COMP
SYNC
REG
SS
FB
______________________________________________________________________________________
SS
I
SS
is in seconds and C
OSC
IN
EN
1.23V
SS
SS
Soft-Start and Reference (SS)
) using following equation:
t
) connected from SS to SGND caus-
SS
LDO
EN
REF
=
1 23
RAMP
.
IN
IN
E/A
V
REF
15
is applied and the internal
V
SS
×
µ
A
1.23V
C
0.3V
is in Farads.
SS
THERMAL
SHDN
1.23V
CPWM
CLK
<1.11V OFF
>1.23V ON
ON/OFF
SS
REGOK
SSA
The MAX5080 features an internal charge pump to
enhance the turn-on of the internal MOSFET, allowing
for operation with input voltages down to 4.5V. Connect
a flying capacitor (C
diode from C+ to BST, as well as a bootstrap capacitor
(C
voltage for the high-side n-channel DMOS switch.
During the on-time, the flying capacitor is charged to
V
flying capacitor (C+) is pumped to two times V
and charge is dumped onto C
regulator voltage across the high-side DMOS driver.
Use a ceramic capacitor of at least 0.1µF for C
C
DVREG
F
BST
V
located as close to the device as possible.
REF
) between BST and LX to provide the gate drive
EN
. During the off-time, the positive terminal of the
ILIM
OVERL
Internal Charge Pump (MAX5080)
BOOTSTRAP
CONTROL
PFM
MANAGEMENT
ILIM
LOGIC
OVERLOAD
F
) between C+ and C-, a boost
PCLK
SCLK
REF_ILIM
REF_PFM
MAX5081
ILIM
CLK
BST
to provide twice the
HIGH-SIDE
CURRENT
SENSE
BST
DVREG
SGND
IN
BST
LX
DVREG
PGND
and