Preliminary Technical Data

ADCMP606/ADCMP607

Rev. PrA | Page 11 of 16

CROSSOVER BIAS POINT

maximum hysteresis that can be applied using this pin is

approximately 160 mV. Figure 18 illustrates the amount of

hysteresis applied as a function of the external resistor value,

and Figure TBD illustrates hysteresis as a function of the current.

In both op amps and comparators, rail-to-rail inputs of this type

have a dual front-end design. Certain devices are active near the

mined point in the common-mode range, a crossover occurs. At

this point, normally V

The hysteresis control pin appears as a 1.25 V bias voltage seen

through a series resistance of 7k ± 20% throughout the hysteresis

control range. The advantages of applying hysteresis in this manner

are improved accuracy, improved stability, reduced component

count, and maximum versatility. An external bypass capacitor is

not recommended on the HYS pin because it impairs the latch

function and often degrades the jitter performance of the device.

As described in the

CC

/2, the direction of the bias current reverses

and the measured offset voltages and currents change.

The ADCMP606/ADCMP607 slightly elaborate on this scheme.

means that at any voltage, the comparator input characteristics

more closely resemble the inputs of nonrail-to-rail ground

sensing comparators, such as the AD8611.

Using/Disabling the Latch Feature section,

hysteresis control need not compromise the latch function.

MINIMUM INPUT SLEW RATE REQUIREMENT

(Remove if device is stable.)

As with most high speed comparators without hysteresis, a

minimum slew rate must be met to ensure that the device does not

oscillate as the input signal crosses the threshold. This oscillation

is due in part to the high input bandwidth of the comparator in

combination with feedback parasitics inherent in the package

and PC board. A minimum slew rate of TBD V/μs ensures clean

output transitions from the ADCMP606/ADCMP607 comparators

unless hysteresis is programmed. In many applications, chattering

due to the absence of hysteresis is not harmful.

Figure 18. Hysteresis vs. R

Control Resistor

HYS