ISL60007 Datasheet, PDF (9/12 Pages) Intersil Corporation – Precision 1.25V and 2.50V, 1.08u-Watt, High Precision FGA Voltage References

ISL60007
400
350
300
250
200
150
100
50
0
1
C_L = 0.01µF
& 10µF + 2kΩ
C_L = 0.1µF
C_L = 0
C_L= 0.001µF
10
100
1000
10000
FIGURE 28. NOISE REDUCTION
100000
V_IN = 3.0V
0.1µF
10µF
V_IN
V_O
ISL60007
GND
0.01µF
2kΩ
10µF
FIGURE 29.
Turn-On Time
The ISL60007 devices operate with ultra-low supply current
and thus the time to bias up internal circuitry to final values
will be longer than with references that require higher
current. Normal turn-on time is typically 4ms. This is shown
in Figure 30. Since devices can vary in supply current down
to 250nA, turn-on time can last up to about 6ms. Care
should be taken in system design to include this delay before
measurements or conversions are started.
3.5
V_IN
3
400nA
2.5
570nA
2
1.5
250nA
1
0.5
0
0
2
4
6
8
10
12
TIME (ms)
FIGURE 30. TURN-ON TIME (+25°C)
Temperature Coefficient
The limits stated for temperature coefficient (tempco) are
governed by the method of measurement. The
overwhelming standard for specifying the temperature drift of
a reference is to measure the reference voltage at two
temperatures, take the total variation, (V_HIGH - V_LOW), and
divide by the temperature extremes of measurement
(T_HIGH - T_LOW). The result is divided by the nominal
reference voltage (at T = 25°C) and multiplied by 10⁶ to yield
ppm/°C. This is the “Box” method for specifying temperature
coefficient.
Typical Application Circuits
V_IN = 5V
R = 200Ω
V_IN
ISL60007
V_OUT
GND
2N2905
2.5V/50mA
0.001µF
FIGURE 31. PRECISION 2.5V, 50mA REFERENCE
9
FN8087.1
May 5, 2005