u-blox EVA-M8M, Hardware Integration Manual

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EVA-M8M - Hardware Integration Manual
UBX-14006179 - R02 Early Production Information Design-in
Page 23 of 45
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NEO-6M C88-M8M
Pin Name Typical Assignment Pin Name Typical Assignment Remarks for Migration
8 RESERVED
Pin 8 and 9 must be
connected together.
RESET_N Reset input
If pin 8 is connected to pin 9 on C88-M8M, the
device always runs. With NEO-6Q, if Reset input
is used, it implements the 3k3 resistor from pin
8 to pin 9. This also works with NEO-7N. If used
with NEO-7N, do not populate the pull-up
resistor.
9 VCC_RF
Can be used for active
antenna or external LNA
supply.
VCC_RF
Can be used for
active antenna or
external LNA
supply.
No difference
10 GND GND GND GND No difference
11 RF_IN GPS signal input RF_IN GPS signal input
For designs with a passive antenna directly
connected to the RF_IN pin, an additional LNA
in front of C88-M8M is recommended in order
to achieve the performance values shown in the
EVA-M8M Data Sheet [1]. The Noise Figure of
the C88-M8M is about 2 dB higher than NEO-
6M.
12 GND GND GND GND No difference
13 GND GND GND GND No difference
14
MOSI/
CFG_COM0 SPI MOSI / Configuration
pin. Leave open if not used.
RESERVED Leave open.
Different functions. Only compatible if this
pin is left open!
15
MISO/
CFG_COM1 SPI MISO / Configuration
pin. Leave open if not used.
RESERVED Leave open.
Different functions. Only compatible if this
pin is left open!
16
CFG_GPS0/
SCK
Power Mode Configuration
pin / SPI Clock. Leave open
if not used.
RESERVED Leave open.
Different functions. Only compatible if this
pin is left open!
17 RESERVED Leave open. RESERVED Leave open. No difference
18 SDA DDC Data SDA
DDC Data / SPI
CS_N No difference if pin 2 is left open. If pin 2 low =
SPI chip select.
19 SCL DDC Clock SCL
DDC Clock / SPI
SCK
No difference for DDC. If pin 2 low = SPI clock.
20 TxD
Serial Port
TxD
Serial Port / SPI
MISO No difference for UART.
If pin 2 low = SPI
MISO.
21 RxD
Serial Port
RxD
Serial Port / SPI
MOSI No difference for UART. If pin 2 low = SPI
MOSI.
22 V_BCKP
Backup supply voltage
V_BCKP
Backup supply
voltage
No difference
23 VCC Supply voltage VCC Supply voltage
24 GND GND GND GND No difference
Table 6: Replacing NEO-6M by C88-M8M
NEO-6M cannot be replaced by C88-M8M if SPI interface or configuration pins (pin 2, pin 14, pin 15 and
pin 16) are used.
For the existing NEO-7M and NEO-M8M designs, C88-M8M is one to one compatible with the exception
of some performance difference.