Datasheet
NXP Semiconductors
UM11183
KITFS85SKTEVM evaluation board
UM11183 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2019. All rights reserved.
User manual Rev. 3 — 6 December 2019
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Table 1. Compensation network
Components VPRE 450 kHz VPRE 2.2 MHz
C18/C19 6.8 nF 1.5 nF
C14/C15 150 pF 22 pF
R6/R10 3.57 kΩ 16.9 kΩ
LPRE 4.7 µH or 6.8 µH 1.5 µH, 2.2 µH or 4.7 µH
4.1.4 BUCK1 and BUCK2 multiphase configuration
The board is designed to work independently with BUCK1 and BUCK2. Due to R11 and
R145, it is possible to connect both connectors together and work in multiphase.
aaa-032767
BUCK1
BUCK2
R11
0
DNP
R145
0
DNP
Figure 4. BUCK1 and BUCK2 multiphase configuration
4.1.5 SPI/I2C
The SPI and I2C buses are connected to KL25Z MCU. The user can use either one or
the other. The choice can be done at start of the FlexGUI or at any time after launch (see
Section 8 "Using FlexGUI").
This kit uses a KL25Z MCU to communicate with FlexGUI. However, if the user wants
to connect the SPI to another MCU, this is possible. In this case, remove J28 and
appropriate jumpers to disconnect the KL25Z MCU (see Figure 5) and connect the
external MCU on J30 connector as shown in Figure 6. In addition to this change, make
sure that the VDDIO voltage domain is the same on MCU side and SBC side.
a
a
a
-
0
3
2
7
6
8
2
4
6
8
10
12
RSTb_SH
FS0b_SH
MISO_SH
MOSI_SH
[3] RSTb
[3] FS0b
[3] MISO
[3] MOSI
[3] CSB
[3] SCLK
SCLK_SH
CSB_SH
1
J28
3
5
7
9
11
Figure 5. SPI connection to KL25Z










