OPA703, OPA704

10

SBOS180A

APPLICATIONS INFORMATION

OPA703 and OPA704 series op amps can operate on 160

µA

quiescent current from a single (or split) supply in the range

of 4V to 12V (

±2V to ±6V), making them highly versatile

and easy to use. The OPA703 is unity-gain stable and offers

1MHz bandwidth and 0.6V/

µs slew rate. The OPA704 is

optimized for gains of 5 or greater with a 3MHz bandwidth

and 3V/

µs slew rate.

Rail-to-rail input and output swing helps maintain dynamic

range, especially in low supply applications. Figure 1 shows

the input and output waveforms for the OPA703 in unity-

gain configuration. Operation is from a

±5V supply with a

100k

Ω load connected to V

sinusoid. Output voltage is approximately 10Vp-p.

Power-supply pins should be bypassed with 1000pF ceramic

capacitors in parallel with 1

µF tantalum capacitors.

OPERATING VOLTAGE

OPA703 and OPA704 series op amps are fully specified and

guaranteed from +4V to +12V over a temperature range of

–40ºC to +85ºC. Parameters that vary significantly with

operating voltages or temperature are shown in the Typical

Performance Curves.

RAIL-TO-RAIL INPUT

The input common-mode voltage range of the OPA703 series

extends 300mV beyond the supply rails at room temperature.

This is achieved with a complementary input stage—an N-

channel input differential pair in parallel with a P-channel

differential pair, as shown in Figure 2. The N-channel pair is

active for input voltages close to the positive rail, typically

(V+) – 2.0V to 300mV above the positive supply, while the P-

channel pair is on for inputs from 300mV below the negative

supply to approximately (V+) – 1.5V. There is a small

transition region, typically (V+) – 2.0V to (V+) – 1.5V, in

which both pairs are on. This 500mV transition region can

vary

±100mV with process variation. Thus, the transition

region (both stages on) can range from (V+) – 2.1V to (V+)

– 1.4V on the low end, up to (V+) – 1.9V to (V+) – 1.6V on

the high end. Within the 500mV transition region PSRR,

CMRR, offset voltage, and offset drift, and THD may vary

compared to operation outside this region.

FIGURE 2. Simplified Schematic.

FIGURE 1. Rail-to-Rail Input and Output.

Input

Output (inverted on scope)

G = +1, V

200

µs/div

V

O

V–

V+

V

V