10

Notes:

General Note: Typical values represent the mean value of all characteriza-

tion units at the nominal operating conditions. Typical drift specifica-

tions are determined by calculating the rate of change of the specified

parameter versus the drift pa-rameter (at nominal operating conditions)

for each characterization unit, and then averaging the individual unit

rates. The corresponding drift figures are normalized to the nominal

operating conditions and show how much drift occurs as the par-ticular

drift parameter is varied from its nominal value, with all other param-

eters held at their nominal operating values. Note that the typical drift

specifications in the tables below may differ from the slopes of the mean

curves shown in the corresponding figures.

1. Avago recommends operation with

V

IN-

= 0 V (tied to GND1).

Limiting V

IN+

to 100 mV will improve DC nonlinearity and nonlinear-

ity drift. If V

IN-

is brought above V

DD1

– 2 V, an internal test mode may

be activated. This test mode is for testing LED coupling and is not

intended for customer use.

2. This is the Absolute Value of Input Offset Change vs. Temperature.

3. Gain is defined as the slope of the best-fit line of differential output

voltage

(V

OUT+

–V

OUT-

) vs. differential input voltage (V

IN+

–V

IN-

)

over the specified input range.

4. This is the Absolute Value of Gain Change vs. Temperature.

5. Nonlinearity is defined as half of the peak-to-peak output deviation

from the best-fit gain line, expressed as a percentage of the full-scale

differential output voltage.

6. NL

100

is the nonlinearity specified over an input voltage range of

±100 mV.

7. The input supply current decreases as the differential input voltage

(V

IN+

–V

IN-

) decreases.

8. The maximum specified output supply current occurs when the

differential input voltage (V

IN+

–V

IN-

) = -200 mV, the maximum rec-

ommended operat-ing input voltage. However, the out-put supply

current will continue to rise for differential input voltages up to

approximately -300 mV, beyond which the output supply current

remains constant.

9. Because of the switched-capacitor nature of the input sigma-delta

con-verter, time-averaged values are shown.

10. When the differential input signal exceeds approximately 308 mV,

the outputs will limit at the typical values shown.

11. Short circuit current is the amount of output current generated

when either output is shorted to V

DD2

or ground.

12. CMRR is defined as the ratio of the differential signal

gain (signal applied differentially between pins 2 and 3)

to the common-mode gain (input pins tied together and the signal

applied to both inputs at the same time), expressed in dB.

13. Output noise comes from two primary sources: chopper noise

and sigma-delta quantization noise. Chopper noise results from

chopper stabilization of the output op-amps. It occurs at a specific

frequency (typically 400 kHz at room temperature), and is not at-

tenuated by the internal output filter. A filter circuit can be easily

added to the external post-amplifier to reduce the total rms output

noise. The internal output filter does eliminate most, but not

all, of the sigma-delta quantization noise. The magnitude of the

output quantization noise is very small at lower frequencies (below

10 kHz) and increases with increasing frequency.

14. CMTI (Common Mode Transient Immunity or CMR, Common Mode

Rejection) is tested by applying an exponentially rising/falling

voltage step on pin 4 (GND1) with respect to pin 5 (GND2). The rise

time of the test waveform is set to approximately 50 ns. The ampli-

tude of the step is adjusted until the differential output (V

OUT+

–V

OUT-

)

exhibits more than a 200 mV deviation from the average output

voltage for more than 1μs. The HCPL-7840 will continue to func-tion

if more than

10 kV/μs common mode slopes are applied, as

long as the breakdown voltage limitations are observed.

15. Data sheet value is the differential amplitude of the transient at the

output of the HCPL-7840 when a 1 V

pk-pk

, 1 MHz square wave with

40 ns rise and fall times is applied to both V

DD1

and V

DD2

.

16. In accordance with UL 1577, each optocoupler is proof tested by ap-

plying an insulation test voltage ≥4500 Vrms for 1 second (leakage

detection current limit, I

I-O

≤ 5 μA). This test is performed before the

100% production test for partial discharge (method b) shown in

IEC/EN/DIN EN 60747-5-2 Insulation Characteristic Table.

17. The Input-Output Momentary Withstand Voltage is a dielectric

voltage rating that should not be interpreted as an input-output

continuous voltage rating. For the continuous voltage rating refer

to the VDE 0884 insulation characteristics table and your equipment

level safety specification.

18. This is a two-terminal measurement: pins 1–4 are shorted together

and pins 5–8 are shorted together.