el5420t Intersil Corporation, el5420t Datasheet - Page 12

• Manufacturer Part Number: el5420t
• Description: 12mhz Rail-to-rail Input-output Operational Amplifier
• Manufacturer: Intersil Corporation

Applications Information
Product Description
The EL5420T is a high voltage rail-to-rail input-output
amplifier with low power consumption. The EL5420T
contains four amplifiers. Each amplifier exhibits beyond the
rail input capability, rail-to-rail output capability, and is unity
gain stable.
The EL5420T features a slew rate of 12V/µs. Also, the
device provides common mode input capability beyond the
supply rails, rail-to-rail output capability, and a bandwidth of
12MHz (-3dB). This enables the amplifiers to offer maximum
dynamic range at any supply voltage.
Operating Voltage, Input and Output Capability
The EL5420T can operate on a single supply or dual supply
configuration. The EL5420T operating voltage ranges from a
minimum of 4.5V to a maximum of 19V. This range allows for
a standard 5V (or ±2.5V) supply voltage to dip to -10%, or a
standard 18V (or ±9V) to rise by +5.5% without affecting
performance or reliability.
The input common-mode voltage range of the EL5420T
extends 500mV beyond the supply rails. Also, the EL5420T
is immune to phase reversal. However, if the common mode
input voltage exceeds the supply voltage by more than 0.5V,
electrostatic protection diodes in the input stage of the
device begin to conduct. Even though phase reversal will not
occur, to maintain optimal reliability it is suggested to avoid
input overvoltage conditions. Figure 28 shows the input
voltage driven 500mV beyond the supply rails and the device
output swinging between the supply rails.
The EL5420T output typically swings to within 50mV of
positive and negative supply rails with load currents of
±5mA. Decreasing load currents will extend the output
voltage range even closer to the supply rails. Figure 29
shows the input and output waveforms for the device in a
unity-gain configuration. Operation is from ±5V supply with a
10kΩ load connected to GND. The input is a 10V
sinusoid and the output voltage is approximately 9.9V
Refer to the “Electrical Specifications” Table beginning on
page 3 for specific device parameters. Parameter variations
with operating voltage, loading and/or temperature are
shown in the “Typical Performance Curves” on page 6.
12
P-P
P-P
.
EL5420T
Output Current
The EL5420T is capable of output short circuit currents of
200mA (source and sink), and the device has built-in
protection circuitry which limits the short circuit current to
±200mA (typical).
To maintain maximum reliability the continuous output
current should never exceed ±70mA. This ±70mA limit is
determined by the characteristics of the internal metal
interconnects. Also, see “Power Dissipation” on page 13 for
detailed information on ensuring proper device operation
and reliability for temperature and load conditions.
Unused Amplifiers
It is recommended that any unused amplifiers be configured
as a unity gain follower. The inverting input should be directly
connected to the output and the non-inverting input tied to
the ground.
Thermal Shutdown
The EL5420T has a built-in thermal protection which
ensures safe operation and prevents internal damage to the
device due to overheating. When the die temperature
reaches +165°C (typical) the device automatically shuts OFF
the outputs by putting them in a high impedance state. When
the die cools by 15°C (typical) the device automatically turns
FIGURE 28. OPERATION WITH BEYOND-THE-RAILS INPUT
FIGURE 29. OPERATION WITH RAIL-TO-RAIL INPUT AND
V
V
S
S
= ±2.5V, T
= ±5V, T
A
A
= +25°C, A
INPUT
= +25°C, A
V
100
V
= 1, V
OUTPUT
= 1, V
µs/DIV
INx
INx
= 10V
= 6V
P-P,
P-P,
100
R
R
L
µs/DIV
L
= 10kΩ to GND
= 10kΩ to GND
September 25, 2009
FN6838.0