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Chip information, Package information – Rainbow Electronics MAX684 User Manual

Page 9

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MAX682/MAX683/MAX684

3.3V-Input to Regulated 5V-Output

Charge Pumps

_______________________________________________________________________________________

9

Power Dissipation

The power dissipated in the MAX682/MAX683/MAX684
depends on output current and is accurately described
by:

P

DISS

= I

OUT

(2V

IN

- V

OUT

)

P

DISS

must be less than that allowed by the package

rating. See the

Absolute Maximum Ratings

for 8-pin

µMAX (MAX683/MAX684) and SO (MAX682) power-
dissipation limits and deratings.

Layout Considerations

All capacitors should be soldered in close proximity to
the IC. Connect ground and power ground through a
short, low-impedance trace. If a high-value resistor is
driving the shutdown input and is picking up noise (i.e.,
frequency jitter at CXP and CXN), bypass SHDN to
GND with a small capacitor (0.01µF).

Paralleling Devices

The MAX682/MAX683/MAX684 can be paralleled to
yield higher load currents. The circuit of Figure 6 can
deliver 500mA at 5V. It uses two MAX682s in parallel.
The devices can share the output capacitors, but each
one requires its own transfer capacitor (C

X

) and input

capacitor. For best performance, the paralleled devices
should operate in the same mode (skip or constant fre-
quency).

Chip Information

TRANSISTOR COUNT: 659

SUBSTRATE CONNECTED TO GND

Package Information

8LUMAXD.EPS