MAX1842EEE Maxim Integrated Products, MAX1842EEE Datasheet - Page 8

• Manufacturer Part Number: MAX1842EEE
• Description: DC/DC Switching Regulators
• Manufacturer: Maxim Integrated Products

Specifications of MAX1842EEE

• Case: ssop
• Dc: 02+
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

1A/2.7A, 1MHz, Step-Down Regulators with
Synchronous Rectification and Internal Switches
(Circuit of Figure 1, T
8
3, 14, 16
13, 15
_______________________________________________________________________________________
PIN
2, 4
10
11
12
1
5
6
7
8
9
NAME
COMP
FBSEL
SHDN
PGND
TOFF
GND
REF
V
SS
FB
LX
IN
CC
LOAD-TRANSIENT RESPONSE
A
= +25°C, unless otherwise noted.)
Shutdown Control Input. Drive SHDN low to disable the reference, control circuitry, and internal
MOSFETs. Drive high or connect to V
Supply Voltage Input—for the internal PMOS power switch.
Connection for the drains of the PMOS power switch and NMOS synchronous-rectifier switch. Connect
the inductor from this node to the output filter capacitor and load.
Soft-Start. Connect a capacitor from SS to GND to limit inrush current during startup.
Integrator Compensation. Connect a capacitor from COMP to V
Integrator Amplifier section.
Off-Time Select Input. Sets the PMOS power switch off-time during constant-off-time operation. Connect a
resistor from TOFF to GND to adjust the PMOS switch off-time.
Feedback Input—for both preset-output and adjustable-output operating modes. Connect directly to
output for fixed-voltage operation or to a resistive divider for adjustable operating modes.
Analog Ground
Reference Output. Bypass REF to GND with a 1µF capacitor.
Feedback Select Input. Selects output voltage. See Table 3 for programming instructions.
Analog Supply Voltage Input. Supplies internal analog circuitry. Bypass V
pass filter. See Figure 1.
Power Ground. Internally connected to the internal NMOS synchronous-rectifier switch.
MAX1842
10μs/div
MAX1842 toc17
Typical Operating Characteristics (continued)
V
50mV/div
I
2A/div
L
OUTPUT
CC
for normal operation.
FUNCTION
I
OUT
= 2.5A, V
LINE-TRANSIENT RESPONSE
CC
for integrator compensation. See
OUT
= 1.5V, R
MAX1842
20μs/div
CC
TOFF
with a 10Ω and 2.2µF low-
Pin Description
= 100kΩ, L = 2.2μH
MAX1842 toc18
0
V
2V/div
V
20mV/div
AC-COUPLED
INPUT
OUTPUT