Neoway N75 - Page 5

N75
Hardware User Guide
Copyright © Neoway Technology Co., Ltd
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Table of Figures
Figure 1-1 Block Diagram .................................................................................................................. 2
Figure 2-1 N75 pin definition (Top View) ............................................................................................ 5
Figure 3-1 Current peaks and voltage drops (GSM/GPRS) ............................................................ 15
Figure 3-2 Recommended design 1 ................................................................................................. 15
Figure 3-3 Recommended design 2 ................................................................................................. 16
Figure 3-4 Recommended design 3 ................................................................................................. 17
Figure 3-5 Recommended design 4 ................................................................................................. 17
Figure 3-6 Reference design of startup controlled by button ........................................................... 19
Figure 3-7 Reference design of startup controlled by MCU ............................................................. 20
Figure 3-8 Reference design of automatic start once powered up .................................................. 20
Figure 3-9 N75 on/off timing ............................................................................................................. 21
Figure 3-10 Reset controlled by button ............................................................................................ 22
Figure 3-11 Reset circuit with triode separating ............................................................................... 22
Figure 3-12 Reset timing of N75 ...................................................................................................... 22
Figure 3-13 USB connection ............................................................................................................ 24
Figure 3-14 Reference design of USB OTG function ....................................................................... 24
Figure 3-15 Reference design of USIM card interface ..................................................................... 26
Figure 3-16 Reference design of UART connection (with flow control) ........................................... 27
Figure 3-17 Reference design of UART connection (without flow control) ...................................... 27
Figure 3-18 Recommended level shifting circuit 1 ........................................................................... 28
Figure 3-19 Recommended level shifting circuit 2 ........................................................................... 29
Figure 3-20 Recommended level shifting circuit 3 ........................................................................... 30
Figure 3-21 SD connection .............................................................................................................. 31
Figure 3-22 SDC SDR timing ........................................................................................................... 32
Figure 3-23 SDC DDR timing ........................................................................................................... 33
Figure 3-24 I2S connection .............................................................................................................. 34
Figure 3-25 I2S timing ...................................................................................................................... 35