Service manual
GX30
6 – 14
CONFIDENTIAL
IC502 VHIBU7870KN-1L (BU7870KN): USB CONTROLLER
In this unit, the terminal with asterisk mark (*) is (open) terminal which is not connected to the outside.
Pin No. Terminal name Input/Output Description of terminal
1 MODESEL1 Input Operation mode switching 1
2 MODESEL2 Input Operation mode switching 2
3 UART_RXD Output UART_RXD output
4 UART_TXD Input UART_TXD input
5 CPUVDD – Digital power supply
6 UART_RTS Input UART_RTS input
7 BSYNC Input BSYNC input
8 UART_CTS Output UART_CTS output
9 BDATA Input BDATA input
10 BCNT Input BDATA input control
11 MODESEL3 Input Operation mode switching 3
12 TXANAOUT Output Hands free sending external output
13 RXANAIN Input Hands free receiving external input
14 GND1 – Ground
15 RXANAOUT Output Hands free receiving output
16 TXANAIN Input Hands free sending input
17* NC – Not used
18 BDATA/CTS Input/Output BDATA/CTS switching external input/output
19 BSYNC/RTS Output BSYNC/RTS switching external output
20 USBD-/TXD Input/Output USBD-/TXD switching external input/output
21 GND2 – Ground
22 USBD+/RXD Input/Output USBD+/RXD switching external input/output
23 CPU_USB_D+ Input/Output CPU_USB_D+ input/output
24 CPU_USB_D- Input/Output CPU_USB_D- input/output
25 REG33 – Power supply voltage for USB
26 PU15 Output PMOS open drain output
27 PUEA Input PU15 control input
28 GND3 – Ground
2021
14 GND1
GND2
MODESEL1
MODESEL2
UART_RXD
UART_TXD
UART_RTS
BSYNC
CPUVDD
USBD-/TXD
BSYNC/RTS
BDATA/CTS
NC
TXANAIN
RXANAOUT
USBD+/RXD
CPU_USB_D+
CPU_USB_D-
REG33
PU15
PUEA
GND3
RXANAIN
TXANAOUT
MODESEL3
BCNT
B DATA
UART_CTS
19 151617
MODE 0,1,2: ON
MODE 3,5: OFF
CPUVDD
CPUVDD
CPUVDD
CPUVDD
DEC
H: ON
L: OFF
CPUVDD
CPUVDD
CPUVDD
CPUVDD
CPUVDD
CPUVDD
MODE 0,1,2: OFF
MODE 3,5: ON
MODE 0,2,3: OFF
MODE 1,5: ON
MODE 0,2,3,5: OFF
MODE 1: ON
MODE 0,2,3,5: L
MODE 1: H
MODE 0,2,3,5: L
MODE 1: H
MODE 0,2,3,5: L
MODE 1: H
MODE 0,1,3,5: H
MODE 2: L
MODE 0,1,5: H
MODE 2,3: L
MODE 0,1,5: H
MODE 2,3: L
MODE 0,1,5: OFF
MODE 2,3: ON
MODE 0,1,3,5: H
MODE 2: L
MODE 0,1,3,5: OFF
MODE 2: ON
10K
10K
MODE 0,1,2: ON
MODE 3,5: OFF
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76421 3 5
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