ISL70444SEH Datasheet, PDF (19/23 Pages) Intersil Corporation – 19MHz Rad Hard 40V Quad Rail-to-Rail Input-Output, Low-Power Operational Amplifiers

ISL70444SEH
Applications Information
Functional Description
The ISL70444SEH contains four high speed and low power op
amps designed to take advantage of its full dynamic input and
output voltage range with rail to rail operation. By offering low
power, low offset voltage, and low temperature drift coupled with
its high bandwidth and enhanced slew rates upwards of 50V/µs,
these op amps are ideal for applications requiring both high DC
accuracy and AC performance. The ISL70444SEH is
manufactured in Intersil’s PR40 silicon-on-insulator process,
which makes this device immune to Single Event Latch-up and
provides excellent radiation tolerance. This makes it the ideal
choice for high reliability applications in harsh radiation-prone
environments.
Operating Voltage Range
The devices are designed to operate with a split supply rail from
±1.35V to ±20V or a single supply rail from 2.7V to 40V. The
ISL70444SEH is fully characterized in production for supply rails
of 5V (±2.5V) and 36V (±18V). The Power Supply Rejection Ratio
is typically 120dB over the full operating voltage range. The worst
case common mode rejection ratio over temperature is within
1.5V to 2V of each rail. When V_CM is inside that range, the CMRR
performance is typically >110dB with ±18V supplies. The
minimum CMRR performance over the -55°C to +125°C
temperature range and radiation is >70dB over the full common
mode input range for power supply voltages from ±2.5V (5V) to
±18V (36V).
Input Performance
The slew enhanced front end is a block that is placed in parallel
with the main input stage and functions based on the input
differential.
Input ESD Diode Protection
The input terminals (IN+ and IN-) have internal ESD protection
diodes to the positive and negative supply rails, series connected
600Ω current limiting resistors and an anti-parallel diode pair
across the inputs.
V+
- ^600Ω
V_IN
+ ^600Ω
V_OUT
R_L
V-
FIGURE 60. INPUT ESD DIODE CURRENT LIMITING, UNITY GAIN
Output Short Circuit Current Limiting
The output current limit has a worst case minimum limit of
±8mA but may reach as high as ±100mA. The op amp can
withstand a short circuit to either rail for a short duration (<1
second) as long as the maximum operating junction temperature
is not violated. This applies to only one amplifier at a given time.
Continued use of the device in these conditions may degrade the
long term reliability of the part and is not recommended. Figure
20 shows the typical short circuit currents that can be expected.
The ISL70444SEH’s current limiting circuitry will automatically
lower the current limit of the device if short circuit conditions
carry on for extended periods in time in an effort to protect itself
from malfunction, however extended operation in this mode will
degrade the output rail-to-rail performance by increasing the
V_OH/V_OL levels.
Output Phase Reversal
Output phase reversal is a change of polarity in the amplifier
transfer function when the input voltage exceeds the supply
voltage. The ISL70444SEH is immune to output phase reversal,
even when the input voltage is 1V beyond the supplies. This is
illustrated in Figure 49.
Power Dissipation
It is possible to exceed the +150°C maximum junction
temperatures under certain load and power supply conditions. It
is therefore important to calculate the maximum junction
temperature (T_JMAX) for all applications to determine if power
supply voltages, load conditions, or package type need to be
modified to remain in the safe operating area. These parameters
are related using Equation 1:
T_JMAX = T_MAX + θ_JA x PD_MAXTOTAL
(EQ. 1)
where:
• P_DMAXTOTAL is the sum of the maximum power dissipation of
each amplifier in the package (PD_MAX)
• PD_MAX for each amplifier can be calculated using Equation 2:
PD_MAX
=
V_S × I_qMAX + (V_S
-
V_OUTMAX
)
×
V_{-----O----U----T----M-----A----X--}
R_L
(EQ. 2)
where:
• T_MAX = Maximum ambient temperature
• θ_JA = Thermal resistance of the package
• PD_MAX = Maximum power dissipation of 1 amplifier
• V_S = Total supply voltage
• I_qMAX = Maximum quiescent supply current of 1 amplifier
• V_OUTMAX = Maximum output voltage swing of the application
19
FN8411.1
June 14, 2013