MAX6161–MAX6168
Precision, Micropower, Low-Dropout, High-
Output-Current, SO-8 Voltage References
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Applications Information
Input Bypassing
For the best line-transient performance, decouple the
input with a 0.1µF ceramic capacitor as shown in the
Typical Operating Circuit. Locate the capacitor as
close to IN as possible. When transient performance is
less important, no capacitor is necessary.
Output/Load Capacitance
Devices in the MAX6161 family do not require an output
capacitor for frequency stability. In applications where
the load or the supply can experience step changes,
an output capacitor of at least 0.1µF will reduce the
amount of overshoot (undershoot) and improve the cir-
cuit’s transient response. Many applications do not
require an external capacitor, and the MAX6161 family
can offer a significant advantage in applications when
board space is critical.
Supply Current
The quiescent supply current of the series-mode
MAX6161 family is typically 100µA and is virtually inde-
pendent of the supply voltage, with only an 8µA/V
(max) variation with supply voltage. Unlike series refer-
ences, shunt-mode references operate with a series
resistor connected to the power supply. The quiescent
current of a shunt-mode reference is thus a function of
the input voltage. Additionally, shunt-mode references
have to be biased at the maximum expected load cur-
rent, even if the load current is not present at the time.
In the MAX6161 family, the load current is drawn from
the input voltage only when required, so supply current
is not wasted and efficiency is maximized at all input
voltages. This improved efficiency reduces power dissi-
pation and extends battery life.
When the supply voltage is below the minimum speci-
fied input voltage (as during turn-on), the devices can
draw up to 400µA beyond the nominal supply current.
The input voltage source must be capable of providing
this current to ensure reliable turn-on.
Output Voltage Hysteresis
Output voltage hysteresis is the change in the input
voltage at T
A
= +25°C before and after the device is
cycled over its entire operating temperature range.
Hysteresis is caused by differential package stress
appearing across the bandgap core transistors. The
typical temperature hysteresis value is 125ppm.
Turn-On Time
These devices typically turn on and settle to within
0.1% of their final value in 50µs to 300µs, depending on
the output voltage (see electrical table of part used).
The turn-on time can increase up to 1.5ms with the
device operating at the minimum dropout voltage and
the maximum load.
