MAX1793
Low-Dropout, Low I
Q
, 1A Linear Regulator
6 _______________________________________________________________________________________
SHUTDOWN RESPONSE
MAX1793 toc14
40µs/div
V
OUT
2V/div
5V/div
V
SHDN
I
OUT
= 100mA
RESET OUTPUT RESPONSE
MAX1793 toc15
1ms/div
V
IN
5V/div
2V/div
2V/div
V
OUT
RST
Typical Operating Characteristics (continued)
(Circuit of Figure 2, V
IN
= +5V, V
SHDN
= V
IN
,V
OUT
= +3.3V, T
A
= +25°C, unless otherwise noted.)
Pin Description
PIN NAME FUNCTION
1, 8, 9, 16 N.C. No Connection. Not internally connected.
2–5 IN
Regulator Input. Supply voltage ranges from +2.5V to +5.5V. Bypass with a 4.7µF capacitor to GND
(see the Capacitor Selection and Regulator Stability). These inputs are internally connected, but they
also must be externally connected for proper operation.
6 RST
Reset Output. Open-drain output is low when V
OUT
is 6% below its nominal value. RST remains low
while the output voltage (V
OUT
) is below the reset threshold and for at least 4ms after V
OUT
rises above
the reset threshold. Connect a 100kΩ pullup resister to OUT to obtain an output voltage.
7 SHDN
Active-Low Shutdown Input. A logic-low disables the output and reduces the supply current to 0.1µA.
In shutdown, the RST output is low and OUT is pulled low through an internal 5kΩ resistance. Connect
SHDN to IN for normal operation.
10 GND
Ground. This pin and the exposed pad also function as a heatsink. Solder both to a large pad or to the
circuit-board ground plane to maximize power dissipation.
11 SET
Voltage-Setting Input. Connect to GND to select the factory-present output voltage. Connect SET to an
external resistor-divider for adjustable-output operation.
12–15 OUT
Regulator Output. Bypass with a 6.8µF, low-ESR capacitor to GND. Connect all OUT pins together at
the IC.
—EP
Exposed Pad. Connect to the ground plane. EP also functions as a heatsink. Solder to the circuit-board
ground plane to maximize thermal dissipation.
