基于Qualcomm 8295的座舱域控制器拆解分析

ResearchInChina对2023年12月推出的电动轿车基于8295的座舱域控制器进行了拆解，并创作了 "SA8295P Series Based Cockpit Domain Controller Analysis and Dismantling" 报告。

座舱域控制器的正式名称是 "Digital Cockpit Head Unit（DHU）" 。座舱域控制器有上配置和下配置两个版本，均采用Qualcomm SA8295P晶片。如果你看一下成本明细，两者的总成本相差很大，高达几十美元。

此次，ResearchInChina拆解了较低配置版本。在本报告中将提供 DHU 概述、主晶片、储存、MCU 和无线的粗略细分。

概述

DHU 很厚，有三个黑色矩形块，支援Bluetooth-Wi-Fi 系统、仅Bluetooth系统和无线系统。

之所以这么厚，是因为DHU采用了上下PCB B2B连接的两层结构。上层PCB负责驾驶舱娱乐和集群。

底部PCB负责摄影机输入、显示输出、麦克风拾音等功能。

主控晶片、储存

核心板PCB安装在顶部PCB上，有包括QAM8295P在内的六个主要晶片、四个电源管理IC（Qualcomm PMM8295AU）和两个DRAM晶片。

储存方面，DHU配备了DRAM晶片和NAND晶片。

DRAM晶片是Micron LPDDR4。FBGA代码为D9ZRT，时脉频率为2,133MHz，为LPDDR4的最低规格。它也是价格最低的汽车级 LPDDR4。对于更高配置的版本，核心板记忆体为32GB，可能是LPDDR4X。

NAND记忆体是Samsung的UFS2.1解决方案（型号：KLUEGAJ1ZD-B0CP），是手机和汽车的通用产品。电压1.8/3.3V，耐温-40℃至85℃，容量256GB。它部署在核心板外部。

单晶片

这次拆解的DHU版本的MCU是Renesas R7F7017113，属于Renesas RH850/F1KH系列，有233个接脚，可以承受-40℃到105℃的温度。

乙太网路

高配置版本和低配置版本在乙太网路方面有很大区别。具体来说，高配置版本有乙太网路交换机，低配置版本只有乙太网路物理层晶片。两个版本的PCB相同，但配置较低的版本在乙太网路区域表面有空位，未实现。

根据拆解，乙太网路物理层晶片为Marvell 88Q2122。该晶片是 IEEE 802.3bw 和 IEEE 802.3bp 定义的 100/1,000BASE-T1 乙太网路物理层收发器 (PHY)，允许透过双绞线传输讯号。它采用标准数位 CMOS 技术并与所有必要的内部主动电路相结合，能够透过双绞线同时接收和传输数据，使其非常适合多种汽车应用。

88Q2122内部整合了媒体相关介面（MDI）所需的匹配终端电阻，透过使用更少的外部元件简化了主机板布局并降低了主机板成本。内建线性稳压器可以产生您所需的所有电压。只需外部3.3V电源即可运作。两种解决方案均支援 1.8V、2.5V 和 3.3V LVCMOS I/O 标准。

无线晶片部署在底部PCB上。可以看到很多晶片的部位都是固定的，主要是用来出口。

此网域控制器中的无线电晶片是NXP SAF7750EL，支援大多数国家的AM/FM。但是，如果您需要 DAB 收音机，则需要新增 TEF3100 或 TEF3200。国外版本的主要无线电晶片一般为SAF4000，这是NXP于2017年推出的全整合软体定义无线电解决方案。SAF4000 支援全球所有广播音讯标准，包括 AM/FM、DAB+、DRM(+) 和 HD。

在本报告中，我们拆解了一款基于Qualcomm 8295的座舱域控制器，并分析了其内部主要部件。

目录

第一章 分解

• 外观结构
• 内部结构
• 界面
• 外壳内部结构
• 印刷电路板

第 2 章 上 PCB 正面主要元件

• 记忆体晶片
• 单晶片
• 乙太网路晶片
• 序列器、解串器

第三章 上PCB背面主要元件

• Bluetooth、Wi-Fi
• 公车对讲机
• 音讯晶片
• 其他晶片

第 4 章 下 PCB 正面主要元件

• 反序列化晶片
• 无线晶片
• 低电压总线延长器

第五章 主要参数及概算费用

• 主控晶片框图
• SA8155/SA8255/SA8295参数对照表
• MCU内部框图
• 乙太网路交换器的内部框图
• 高配置版本的序列化和反序列化配置
• 无线和音讯架构图
• 高配版本无线拓扑
• 主要零件型号及价格

ResearchInChina dismantled 8295-based cockpit domain controller of an electric sedan launched in December 2023, and produced the report SA8295P Series Based Cockpit Domain Controller Analysis and Dismantling.

The official name of the cockpit domain controller is "Digital Cockpit Head Unit (DHU)". The cockpit domain controller has two versions, high configuration and low configuration, both of which use Qualcomm SA8295P chips. In terms of cost breakdown, their total cost differs greatly, up to tens of US dollars.

What ResearchInChina dismantled this time is the low configuration version. This article carries out a rough dismantling analysis on the DHU, involving overview, master chip, storage, MCU and radio.

Overview

The DHU looks thick, with three black rectangular blocks, corresponding to a Bluetooth-WiFi system, a Bluetooth-only system, and a radio system.

The reason why it is thick is that the DHU adopts the two-layer design of upper and lower PCBs which are connected via B2B. The upper board is responsible for cockpit entertainment and cluster.

As concerns function, the lower board is responsible for providing such functions as camera input, display output, and microphone pickup.

Master Chip and Storage

The core board substrate is mounted on the upper board and is equipped with QAM8295P and 6 main chips, including 4 power management ICs (Qualcomm PMM8295AU) and 2 DRAM chips.

In terms of storage, the DHU packs DRAM and NAND chips.

Wherein, the DRAM chip is Micron LPDDR4. The FBGA Code is D9ZRT and the clock frequency is 2133MHz, the lowest specifications in LPDDR4. It is also the lowest-priced automotive grade LPDDR4. As for the high configuration version, the core board memory is 32GB and may be LPDDR4X.

The NAND memory is Samsung's UFS2.1 solution (model: KLUEGAJ1ZD-B0CP), a general-purpose product for mobile phones and automobiles. It features voltage of 1.8/3.3V, resistance to temperatures of -40-degree C~85-degree C, and capacity of 256GB. It is deployed outside the core board.

MCU

In the DHU version disassembled this time, the MCU is Renesas R7F7017113, which belongs to Renesas RH850/F1KH series, has 233 pins, and can resist temperatures of -40-degree C~105-degree C. The high configuration version of the DHU uses Infineon TC387 as its MCU.

Ethernet

The high and low configuration versions vary greatly in terms of Ethernet. Specifically, the high configuration version has an Ethernet switch, while the low configuration version only has an Ethernet physical layer chip. The PCB of the two versions is the same, except that the low configuration version leaves space on the surface of the Ethernet area, not mounted.

According to the dismantling, the Ethernet physical layer chip is Marvell 88Q2122. This chip is a 100/1000BASE-T1 Ethernet physical layer transceiver (PHY) defined by IEEE 802.3bw and IEEE 802.3bp, enabling signal transmission on a twisted pair. Using standard digital CMOS technology, combined with all internal active circuits required, it can simultaneously receive and send data on a twisted pair, which is very suitable for multiple automotive applications.

88Q2122 internally integrates the matched termination resistors required for the media-dependent interface (MDI), thereby simplifying the motherboard layout and lowering the motherboard cost as fewer external components are used. Its built-in linear regulator can generate all voltages required. It only needs a 3.3V external power supply to run. Both solutions support 1.8V, 2.5V and 3.3V LVCMOS I/O standards.

The radio chip is deployed on the lower PCB. It can be seen that there are many positions reserved for chips, mainly on account of export.

The radio chip of this domain controller is NXP SAF7750EL, which can correspond to AM/FM in most countries. Yet if the DAB radio is needed, TEF3100 or TEF3200 will need to be added. The main radio chip of the overseas version is generally SAF4000, a fully integrated software-defined radio solution launched by NXP in 2017. SAF4000is compatible with all global broadcast audio standards including AM/FM, DAB+, DRM(+) and HD.

Table of Contents

1 Disassembly

• 1.1 Appearance and Structure
• 1.2 Internal Structure
• 1.3 Interfaces
• 1.4 Internal Structure of Housing
• 1.5 PCBs

2 Main Components on the Front of the Upper PCB

• 2.1 Memory Chip
• 2.2 MCU
• 2.3 Ethernet Chip
• 2.4 Serializer and Deserializer

3 Main Components on the Back of the Upper PCB

• 3.1 Bluetooth and WiFi
• 3.2 Bus Transceiver
• 3.3 Audio Chip
• 3.4 Other Chips

4 Main components on the Front of the Lower PCB

• 4.1 Deserialization Chip
• 4.2 Radio Chip
• 4.3 Low-voltage Bus Extender

5 Key Parameters and Estimated Cost

• 5.1 Block Diagram of Master Chip
• 5.2 SA8155/SA8255/SA8295 Parameter Comparison Table
• 5.3 Internal Block Diagram of MCU
• 5.4 Internal block diagram of Ethernet Switch
• 5.5 Serialization and Deserialization Configurations of High Configuration Version
• 5.6 Radio and Audio Architecture Diagram
• 5.7 Radio Topology of High Configuration Version
• 5.8 Key Component Models and Prices