LTC2951-1 how to connect to a DC/DC converter with EN pin with pull down resistor

Question

Hi, 
 I am trying to use a LTC2951-1 to turn on a DC/DC converter which EN pin is enabled HIGH and has a pull-down resistor. According to the datasheet, the EN pin must be pulled high externally. 
 If I place a pull up resistor between Vin and EN pin, would not the DC/DC converter be always on? or at least turned on momentarily when the power is plugged in? 
 Kind regards,

ADIApproved · Accepted Answer

Refer to graph "2951 G13" on the page#5 of the datasheet. This is the graph for EN voltage vs. Vin. As you can see when Vin is below 1V, EN voltage does rise towards Vin but as soon as Vin crosses 1V, EN pulls low and stays low unless changed by the part. For most of the DC/DC controllers, EN pin (SHDN pin) threshold is above 1.28V. So, DC/DC should not turn on.)

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LTC2951-1 how to connect to a DC/DC converter with EN pin with pull down resistor