P9241-G-EVK Evaluation Kit User Manual
© 2019 Integrated Device Technology, Inc.
8
March 1, 2019
Figure 5. TH_COIL1, R60, and RC67 Location in the Schematic
Figure 6. TH_COIL1, R60, and RC67 PCB Location
External Buck Regulator
To operate at a fixed 127.7kHz frequency, the P9241-G-EVK has adopted an MP2229 buck IC to adjust the power transfer between the
transmitter and receiver. GPIO_A4 and GPIO_B4 are assigned to adjust the MP2229 FB control. The MP2229 is operating at a fixed 500kHz
frequency on the board. The buck regulator power stage is designed to accommodate a wide range of input voltages. The feedback loop and
the external PWM signal are designed for the MP2229 and changing this circuit is not recommended. The resolution of the MP2229 is
approximately 35mV. The buck and external components in the PCB layout should be isolated from any noise generating circuits.
Figure 7. Buck Regulator Location in the Schematic
R60
10K
C67
0.1uF
O
T
P
O
T
P
t
TH_Coil1
COIL TEMPERATURE SENSING
LDO33
R13 18K
C10
22uF
R79
NP
R16
5.1K
BK_EN
C6
22uF
C11
0.1uF
BK_VIN
C14
NP
C15
0.1uF
Q12
NP
C71
NP
C9 0.1uF
R96
0
R7 10
R11
150K
C4
22uF
R97
0
C12
0.1uF
C5
0.1uF
L3
10uH
BK_ADJ
R14
3.3K
BK_VIN
U1
MP2229
VCC
9
EN
4
LPM
5
FREQ/SY NC
8
BST
10
SW1
2
FB
6
SS
7
IN
3
SW2
11
G
N
D
1
1
IN
P
A
D
15
R67
0
C16
0.1uF
C13
NP
R12
30k
BK_FB
R95
10K
R66
NP
R15
30k
D6
SMAJ20CA-13-F
BK_SW
