Low-Voltage, Single 8-to-1 and

Dual 4-to-1 Cal-Multiplexers

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13

Single-Supply Operation

The MAX4539/MAX4540 operate from a single supply

between +2.7V and +12V when V- is connected to

GND. All of the bipolar precautions must be observed.

However, these parts are optimized for ±5V operation,

and most AC and DC characteristics are degraded sig-

nificantly when departing from ±5V. As the overall sup-

ply voltage (V+ to V-) is lowered, switching speed,

on-resistance, off isolation, and distortion will degrade.

(see the

Typical Operating Characteristics section).

Single-supply operation also limits signal levels and

interferes with ground referenced signals. When V- = 0,

AC signals are limited to -0.3V. Voltages below -0.3V can

be clipped by the internal ESD-protection diodes, and

the parts can be damaged if excessive current flows.

Power Up

During power up, on-chip latches will strobe whatever

addresses are present if EN goes high before LATCH

reaches a logic high. When this condition occurs, one of

the internal dividers connected between the supplies

may inadvertently turn on, causing higher supply current

(~200µA supply current) when the enable input is tog-

gled. Avoid this condition by ensuring that EN pin stays

low until the remaining logic inputs are valid. To accom-

plish this, connect a resistor from EN to ground or apply

a low voltage to EN before the other logic inputs go high.

Power Off

When power to the MAX4539/MAX4540 is off (i.e., V+ =

V- = 0), the Absolute Maximum Ratings still apply. This

means that neither logic-level inputs on NO_ nor sig-

nals on COM_ can exceed ±0.3V. Voltages beyond

±0.3V cause the internal ESD-protection diodes to con-

duct, and the parts can be damaged if excessive cur-

rent flows.

Chip Information

TRANSISTOR COUNT: 561

Test Circuits/Timing Diagrams

50%

50%

V+

0V

0V

LOGIC

INPUT

SWITCH

OUTPUT

+5V

-5V

GND

V+

V+

V+

A1

A2

V-

EN

LATCH

CAL

A0

NO1

NO2–NO7

NO8

COM

+3V

-3V

50

Ω

MAX4539

300

Ω

35pF

A1

A0

+5V

-5V

GND

V+

V-

EN

NO1B

NO2B–NO3B

NO1A–NO2A

NO4B

COMB

+3V

50

Ω

MAX4540

300

Ω

35pF

90%

90%

-3V

LATCH

CAL

Figure 1. Transition Time