LTC5582 datasheet(14/16 Pages) LINER

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LTC5582

5582f

applicaTions inForMaTion

Figure 12. 2nd-Order Temperature Compensation Coefficient

TC2 vs RT2 Value

RT2 (k)

160

120

200

5582 F12

TC2

detV2

Figure 13. Enable Pin Simplified Circuit

Enable Interface

A simplified schematic of the EN Pin interface is shown

in Figure 13. The enable voltage necessary to turn on the

LTC5582 is 1V. To disable or turn off the chip, this volt-

age should be below 0.4V. It is important that the voltage

applied to the EN pin should never exceed VCC by more

than 0.3V. Otherwise, the supply current may be sourced

through the upper ESD protection diode connected at the

EN pin. Under no circumstances should voltage be applied

to the EN Pin before the supply voltage is applied to the

VCC pin. If this occurs, damage to the IC may result.

Supply Voltage Ramping

Fast ramping of the supply voltage can cause a current

glitch in the internal ESD protection circuits. Depending on

the supply inductance, this could result in a supply voltage

overshooting at the initial transient that exceeds the maxi-

mum rating. A supply voltage ramp time of greater than

1msisrecommended.Incasethisvoltageramptimeisnot

controllable, a small (i.e., 1.5Ω) series resistor should be

inserted in-between VCCPinandthesupplyvoltagesource

to mitigate the problem and self-protect the IC. The R1

shown in Figure 1 is served for this purpose.

52k

VCC

5582 F13

52k

LTC5582 Datasheet(PDF) 14 Page - Linear Technology