NXP Semiconductors KIT34932SEKEVB, User Manual, Page: 19 / 39

Getting to Know the Hardware
KT34FS6407-34FS6408UG User’s Guide Rev. 1.0 8/2015
Freescale Semiconductor, Inc. 19
4.8.2 Second Resistor Bridge - V
DRIFT
Monitoring
To increase the safety level of an application, a second resistor bridge has been added. This bridge generates the same voltage as the
bridge connected to FB_core pin. If the difference between voltages is greater than V
DRIFT
, the FS state machine is impacted.
Invoking this functionality involves both the board hardware and the software configuration. On the hardware side, the second resistor
bridge must be configured by jumper J18, as shown in the
Figure 5 , and adjusted by the potentiometer R17 to set the same voltage as on
the first bridge. Software sets registers INIT_Vreg1 (bit Vcore_FB to 1) and register INIT_FSSM1 (bit IO_1_FS to 1).
Figure 5. Second Resistor Bridge
Table 8. V
DRIFT
Monitoring Settings
V
CORE
(V)
Hardware Settings
J15 J18
1.23 1+2 3+4
3.3 3+4 1+2
V
CORE
V
C O R E
V
C O R E
J 15
IO _ 1 V
C O R E
F B D rift E n a ble