Yes it is possible. Have Peer Association of L3 switch with NTP Server & server association of same L3 switch with other network devices ( clients )...

ntp peer ip-address

[normal-sync] [version number]

[key key-id] [source interface]

[prefer]

Forms a peer association

with another system

ntp server ip-address [version

number] [key key-id] [source

interface] [prefer]

Forms a server

association with another

system

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NTP Global Configuration Commands

!--- For the client:

clock timezone EST -5 ????

ntp source loopback 0 ?????

ntp server ip_address key 1

ntp peer ip_address

!--- This is for a peer association.

ntp authenticate

ntp authentication-key 1 md5 xxxx

ntp trusted-key 1

!--- For the server:

clock timezone EST -5

clock summer-time EDT recurring 1 Sun Apr 3:00 last Sun Oct 3:00

clock calendar-valid

ntp source loopback0

ntp update-calendar

!--- This is optional:

interface vlan_id ntp broadcast

!--- This sends NTP broadcast packets.

ntp broadcast client

!--- This receives NTP broadcast packets.

ntp authenticate

ntp authentication-key 1 md5 xxxxx

ntp trusted-key 1

ntp access-group access-list

!--- This provides further security, if needed.

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HTH...