DATASHEET Raspberry Pi Compute Module 3+ Raspberry Pi Compute Module 3+ Lite Release 1, January 2019 Copyright 2019 Raspberry Pi (Trading) Ltd. All rights reserved. Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 Table 1: Release History Release Date Description 1 28/01/2019 First release The latest release of this document can be found at https://www.raspberrypi.org 1 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 Contents 1 Introduction 5 2 Features 2.1 Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 Peripherals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3 Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 6 6 6 3 Block Diagram 7 4 Mechanical Specification 8 5 Pin Assignments 9 6 Electrical Specification 7 Power Supplies 13 7.1 Supply Sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 7.2 Power Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 8 Booting 14 9 Peripherals 9.1 GPIO . . . . . . . . . . . . . . . . . . . . 9.1.1 GPIO Alternate Functions . . . . . 9.1.2 Secondary Memory Interface (SMI) 9.1.3 Display Parallel Interface (DPI) . . 9.1.4 SD/SDIO Interface . . . . . . . . . 9.2 CSI (MIPI Serial Camera) . . . . . . . . . 9.3 DSI (MIPI Serial Display) . . . . . . . . . 9.4 USB . . . . . . . . . . . . . . . . . . . . . 9.5 HDMI . . . . . . . . . . . . . . . . . . . . 9.6 Composite (TV Out) . . . . . . . . . . . . 15 15 16 17 17 18 18 18 18 18 19 11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Thermals 19 10.1 Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 11 Availability 19 12 Support 19 2 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 List of Figures 1 2 3 CM3+ Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 CM3+ Mechanical Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Digital IO Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 List of Tables 1 2 3 4 5 6 7 8 9 10 Release History . . . . . . . . . . . . . . . . . . Compute Module 3+ SODIMM Connector Pinout Pin Functions . . . . . . . . . . . . . . . . . . . Absolute Maximum Ratings . . . . . . . . . . . DC Characteristics . . . . . . . . . . . . . . . . Digital I/O Pin AC Characteristics . . . . . . . . Power Supply Operating Ranges . . . . . . . . . Mimimum Power Supply Requirements . . . . . GPIO Bank0 Alternate Functions . . . . . . . . . GPIO Bank1 Alternate Functions . . . . . . . . . 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 9 10 11 12 12 13 14 16 17 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 1 Introduction The Raspberry Pi Compute Module 3+ (CM3+) is a range of DDR2-SODIMM-mechanically-compatible System on Modules (SoMs) containing processor, memory, eMMC Flash (on non-Lite variants) and supporting power circuitry. These modules allow a designer to leverage the Raspberry Pi hardware and software stack in their own custom systems and form factors. In addition these modules have extra IO interfaces over and above what is available on the Raspberry Pi model A/B boards, opening up more options for the designer. The CM3+ contains a BCM2837B0 processor (as used on the Raspberry Pi 3B+), 1Gbyte LPDDR2 RAM and eMMC Flash. The CM3+ is currently available in 4 variants, CM3+/8GB, CM3+/16GB, CM3+/32GB and CM3+ Lite, which have 8, 16 and 32 Gigabytes of eMMC Flash, or no eMMC Flash, respectively. The CM3+ Lite product is the same as CM3+ except the eMMC Flash is not fitted, and the SD/eMMC interface pins are available for the user to connect their own SD/eMMC device. Note that the CM3+ is electrically identical and, with the exception of higher CPU z-height, physically identical to the legacy CM3 products. CM3+ modules require a software/firmware image dated November 2018 or newer to function correctly. 5 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 2 2.1 Features Hardware * Low cost * Low power * High availability * High reliability - Tested over millions of Raspberry Pis Produced to date - Module IO pins have 15 micro-inch hard gold plating over 2.5 micron Nickel 2.2 Peripherals * 48x GPIO * 2x I2C * 2x SPI * 2x UART * 2x SD/SDIO * 1x HDMI 1.3a * 1x USB2 HOST/OTG * 1x DPI (Parallel RGB Display) * 1x NAND interface (SMI) * 1x 4-lane CSI Camera Interface (up to 1Gbps per lane) * 1x 2-lane CSI Camera Interface (up to 1Gbps per lane) * 1x 4-lane DSI Display Interface (up to 1Gbps per lane) * 1x 2-lane DSI Display Interface (up to 1Gbps per lane) 2.3 Software * ARMv8 Instruction Set * Mature and stable Linux software stack - Latest Linux Kernel support - Many drivers upstreamed - Stable and well supported userland - Full availability of GPU functions using standard APIs 6 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 Block Diagram EMMC_EN_N_1V8 IO Expander HDMI_HPD_N_1V8 VBAT Core SMPS 3V3 1V8 VDAC TVDAC VDD_GPIO0-27 GPIO[0:27] VDD_GPIO28-45 GPIO[28:45] 200 Pin SODIMM Connector 3 CSI CAM0 CSI CAM1 DSI DISP0 DSI DISP1 CM CHOKES HDMI CEC, DDC TV DAC BCM2837B0 GPIO BANK0 GPIO BANK1 1GByte LPDDR2 2 Lane CSI Camera 4 Lane CSI Camera 2 Lane DSI Display 4 Lane DSI Display HDMI TMDS CLOCK & DATA 4GByte eMMC (CM3 only) HDMI CEC & I2C USB USB_OTGID USB2 JTAG 3V3 SD I/O VOLTAGE SD_CMD, Dx SD_CLK RUN RUN 3V3 EMMC_DISABLE_N SDX_CLK (CM3+ Lite only) 1V8 CM3+ eMMC I/O Voltage fixed at 1V8 CM3+ Lite SD I/O Voltage supplied from SDX_VDD SDX_CMD, Dx (CM3+ Lite only) SDX_VDD (CM3+ Lite only) Figure 1: CM3+ Block Diagram 7 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 4 Mechanical Specification The CM3+ modules conform to JEDEC MO-224 mechanical specification for 200 pin DDR2 (1.8V) SODIMM modules and therefore should work with the many DDR2 SODIMM sockets available on the market. (Please note that the pinout of the Compute Module is not the same as a DDR2 SODIMM module; they are not electrically compatible.) The SODIMM form factor was chosen as a way to provide the 200 pin connections using a standard, readily available and low cost connector compatible with low cost PCB manufacture. The maximum component height on the underside of the Compute Module is 1.2mm. The maximum component height on the top side of the Compute Module is 2.5mm. The Compute Module PCB thickness is 1.0mm +/- 0.1mm. Note that the location and arrangement of components on the Compute Module may change slightly over time due to revisions for cost and manufacturing considerations; however, maximum component heights and PCB thickness will be kept as specified. Figure 2 gives the CM3+ mechanical dimensions. Figure 2: CM3+ Mechanical Dimensions 8 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 5 Pin Assignments CM3+ CM3+ Lite GND GPIO0 GPIO1 GND GPIO2 GPIO3 GND GPIO4 GPIO5 GND GPIO6 GPIO7 GND GPIO8 GPIO9 GND GPIO10 GPIO11 GND GPIO0-27_VDD PIN 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 PIN 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 CM3+ CM3+ Lite EMMC_DISABLE_N NC SDX_VDD NC SDX_VDD GND NC SDX_CLK NC SDX_CMD GND NC SDX_D0 NC SDX_D1 GND NC SDX_D2 NC SDX_D3 GND GPIO28 GPIO29 GND GPIO30 GPIO31 GND GPIO0-27_VDD 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 90 92 94 96 98 100 102 104 106 108 110 112 114 116 118 120 122 124 126 128 130 132 134 136 138 140 142 144 146 148 150 152 154 156 158 160 162 164 166 168 170 172 174 176 178 180 182 184 186 188 190 192 194 196 198 200 GPIO28-45_VDD GND GPIO32 GPIO33 GND GPIO34 GPIO35 GND GPIO36 GPIO37 GND GPIO38 GPIO39 GND GPIO40 GPIO41 GND GPIO42 GPIO43 GND GPIO44 GPIO45 GND HDMI_HPD_N_1V8 EMMC_EN_N_1V8 GND DSI1_DP0 DSI1_DN0 GND DSI1_CP DSI1_CN GND DSI1_DP3 DSI1_DN3 GND DSI1_DP2 DSI1_DN2 GND DSI1_DP1 DSI1_DN1 GND NC NC NC NC NC GND CAM0_DP0 CAM0_DN0 GND CAM0_CP CAM0_CN GND CAM0_DP1 CAM0_DN1 GND NC NC NC NC NC GND TVDAC USB_OTGID GND VC_TRST_N VC_TDI VC_TMS VC_TDO VC_TCK GND 1V8 1V8 GND VDAC 3V3 3V3 GND VBAT VBAT KEY GPIO28-45_VDD 41 GND 43 GPIO12 45 GPIO13 47 GND 49 GPIO14 51 GPIO15 53 GND 55 GPIO16 57 GPIO17 59 GND 61 GPIO18 63 GPIO19 65 GND 67 GPIO20 69 GPIO21 71 GND 73 GPIO22 75 GPIO23 77 GND 79 GPIO24 81 GPIO25 83 GND 85 GPIO26 87 GPIO27 89 GND 91 DSI0_DN1 93 DSI0_DP1 95 GND 97 DSI0_DN0 99 DSI0_DP0 101 GND 103 DSI0_CN 105 DSI0_CP 107 GND 109 HDMI_CLK_N 111 HDMI_CLK_P 113 GND 115 HDMI_D0_N 117 HDMI_D0_P 119 GND 121 HDMI_D1_N 123 HDMI_D1_P 125 GND 127 HDMI_D2_N 129 HDMI_D2_P 131 GND 133 CAM1_DP3 135 CAM1_DN3 137 GND 139 CAM1_DP2 141 CAM1_DN2 143 GND 145 CAM1_CP 147 CAM1_CN 149 GND 151 CAM1_DP1 153 CAM1_DN1 155 GND 157 CAM1_DP0 159 CAM1_DN0 161 GND 163 USB_DP 165 USB_DM 167 GND 169 HDMI_CEC 171 HDMI_SDA 173 HDMI_SCL 175 RUN 177 VDD_CORE (DO NOT CONNECT)179 GND 181 1V8 183 1V8 185 GND 187 VDAC 189 3V3 191 3V3 193 GND 195 VBAT 197 VBAT 199 Table 2: Compute Module 3+ SODIMM Connector Pinout Table 2 gives the Compute Module 3+ pinout and Table 3 gives the pin functions. 9 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 Pin Name DIR Voltage Ref PDNa State If Unused Description/Notes RUN and Boot Control (see text for usage guide) RUN EMMC DISABLE N EMMC EN N 1V8 I I O 3V3b 3V3b 1V8 Pull High Pull High Pull High Leave open Leave open Leave open Has internal 10k pull up Has internal 10k pull up Has internal 2k2 pull up I/O I/O GPIO0-27 VDD GPIO28-45 VDD Pull or Hi-Zc Pull or Hi-Zc Leave open Leave open GPIO Bank 0 GPIO Bank 1 O I/O I/O SDX VDD SDX VDD SDX VDD Pull High Pull High Pull High Leave open Leave open Leave open Primary SD interface CLK Primary SD interface CMD Primary SD interface DATA I/O I 3V3 Z Leave open Tie to GND Serial interface OTG pin detect I/O I/O I/O O O I 3V3b 3V3b 3V3 1V8 Zf Zf Z Z Z Pull High Leave open Leave open Leave open Leave open Leave open Leave open DDC Clock (5.5V tolerant) DDC Data (5.5V tolerant) CEC (has internal 27k pull up) HDMI serial clock HDMI serial data HDMI hotplug detect - Z Z Leave open Leave open Serial clock Serial data - Z Z Leave open Leave open Serial clock Serial data Z Z Leave open Leave open Serial clock Serial data GPIO GPIO[27:0] GPIO[45:28] Primary SD Interfaced,e SDX CLK SDX CMD SDX Dx USB Interface USB Dx USB OTGID HDMI Interface HDMI HDMI HDMI HDMI HDMI HDMI SCL SDA CEC CLKx Dx HPD N 1V8 CAM0 (CSI0) 2-lane Interface CAM0 Cx CAM0 Dx I I CAM1 (CSI1) 4-lane Interface CAM1 Cx CAM1 Dx I I DSI0 (Display 0) 2-lane Interface DSI0 Cx DSI0 Dx O O - DSI1 (Display 1) 4-lane Interface DSI1 Cx DSI1 Dx O O - Z Z Leave open Leave open Serial clock Serial data O - Z Leave open Composite video DAC output I I I I O 3V3 3V3 3V3 3V3 3V3 Z Z Z Z O Leave open Leave open Leave open Leave open Leave open Has internal 50k pull up Has internal 50k pull up Has internal 50k pull up Has internal 50k pull up Has internal 50k pull up TV Out TVDAC JTAG Interface TMS TRST N TCK TDI TDO a The PDN column indicates power-down state (when RUN pin LOW) Must be driven by an open-collector driver c GPIO have software enabled pulls which keep state over power-down d Only available on Lite variants e The CM will always try to boot from this interface first f Requires external pull-up resistor to 5V as per HDMI spec b Table 3: Pin Functions 10 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 6 Electrical Specification Caution! Stresses above those listed in Table 4 may cause permanent damage to the device. This is a stress rating only; functional operation of the device under these or any other conditions above those listed in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Symbol Parameter Minimum Maximum Unit VBAT Core SMPS Supply -0.5 6.0 V 3V3 3V3 Supply Voltage -0.5 4.10 V 1V8 1V8 Supply Voltage -0.5 2.10 V VDAC TV DAC Supply -0.5 4.10 V GPIO0-27 VDD GPIO0-27 I/O Supply Voltage -0.5 4.10 V GPIO28-45 VDD GPIO28-45 I/O Supply Voltage -0.5 4.10 V SDX VDD Primary SD/eMMC Supply Voltage -0.5 4.10 V Table 4: Absolute Maximum Ratings DC Characteristics are defined in Table 5 11 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 Symbol Parameter voltagea Conditions Minimum Typical Maximum Unit VDD IO = 1.8V VDD IO = 2.7V VDD IO = 3.3V - - 0.6 0.8 0.9 V V V VIL Input low VIH Input high voltagea VDD IO = 1.8V VDD IO = 2.7V VDD IO = 3.3V 1.0 1.3 1.6 - - V V V IIL Input leakage current TA = +85 C - - 5 A CIN Input capacitance - - 5 - pF VOL Output low voltageb VDD IO = 1.8V, IOL = -2mA VDD IO = 2.7V, IOL = -2mA VDD IO = 3.3V, IOL = -2mA - - 0.2 0.15 0.14 V V V VOH Output high voltageb VDD IO = 1.8V, IOH = 2mA VDD IO = 2.7V, IOH = 2mA VDD IO = 3.3V, IOH = 2mA 1.6 2.5 3.0 - - V V V IOL Output low currentc VDD IO = 1.8V, VO = 0.4V VDD IO = 2.7V, VO = 0.4V VDD IO = 3.3V, VO = 0.4V 12 17 18 - - mA mA mA IOH Output high currentc VDD IO = 1.8V, VO = 1.4V VDD IO = 2.7V, VO = 2.3V VDD IO = 3.3V, VO = 2.3V 10 16 17 - - mA mA mA RP U Pullup resistor - 50 - 65 k RP D Pulldown resistor - 50 - 65 k a Hysteresis enabled Default drive strength (8mA) c Maximum drive strength (16mA) b Table 5: DC Characteristics AC Characteristics are defined in Table 6 and Fig. 3. Pin Name Symbol Parameter Minimum Typical Maximum Unit Digital outputs trise 10-90% rise timea - 1.6 - ns Digital outputs tf all 90-10% fall timea - 1.7 - ns GPCLK tJOSC Oscillator-derived GPCLK cycle-cycle jitter (RMS) - - 20 ps GPCLK tJP LL PLL-derived GPCLK cycle-cycle jitter (RMS) - - 48 ps a Default drive strength, CL = 5pF, VDD IOx = 3.3V Table 6: Digital I/O Pin AC Characteristics 12 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 tfall trise DIGITAL OUTPUT Figure 3: Digital IO Characteristics 7 Power Supplies The Compute Module 3+ has six separate supplies that must be present and powered at all times; you cannot leave any of them unpowered, even if a specific interface or GPIO bank is unused. The six supplies are as follows: 1. VBAT is used to power the BCM2837 processor core. It feeds the SMPS that generates the chip core voltage. 2. 3V3 powers various BCM2837 PHYs, IO and the eMMC Flash. 3. 1V8 powers various BCM2837 PHYs, IO and SDRAM. 4. VDAC powers the composite (TV-out) DAC. 5. GPIO0-27 VREF powers the GPIO 0-27 IO bank. 6. GPIO28-45 VREF powers the GPIO 28-45 IO bank. Supply Descripion Minimum Typical Maximum Unit VBAT Core SMPS Supply 2.5 - 5.0 + 5% V 3V3 3V3 Supply Voltage 3.3 - 5% 3.3 3.3 + 5% V 1V8 1V8 Supply Voltage 1.8 - 5% 1.8 1.8 + 5% V VDAC TV DAC Supplya 2.5 - 5% 2.8 3.3 + 5% V GPIO0-27 VDD GPIO0-27 I/O Supply Voltage 1.8 - 5% - 3.3 + 5% V GPIO28-45 VDD GPIO28-45 I/O Supply Voltage 1.8 - 5% - 3.3 + 5% V SDX VDD Primary SD/eMMC Supply Voltage 1.8 - 5% - 3.3 + 5% V a Requires a clean 2.5-2.8V supply if TV DAC is used, else connect to 3V3 Table 7: Power Supply Operating Ranges 13 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 7.1 Supply Sequencing Supplies should be staggered so that the highest voltage comes up first, then the remaining voltages in descending order. This is to avoid forward biasing internal (on-chip) diodes between supplies, and causing latch-up. Alternatively supplies can be synchronised to come up at exactly the same time as long as at no point a lower voltage supply rail voltage exceeds a higher voltage supply rail voltage. 7.2 Power Requirements Exact power requirements will be heavily dependent upon the individual use case. If an on-chip subsystem is unused, it is usually in a low power state or completely turned off. For instance, if your application does not use 3D graphics then a large part of the core digital logic will never turn on and need power. This is also the case for camera and display interfaces, HDMI, USB interfaces, video encoders and decoders, and so on. Powerchain design is critical for stable and reliable operation of the Compute Module 3+. We strongly recommend that designers spend time measuring and verifying power requirements for their particular use case and application, as well as paying careful attention to power supply sequencing and maximum supply voltage tolerance. Table 8 specifies the recommended minimum power supply outputs required to power the Compute Module 3+. Supply Minimum Requirement Unit VBAT (CM1) 2000a mW VBAT (CM3,3L) 3500a mW 3V3 250 mA 1V8 250 mA VDAC 25 mA GPIO0-27 VDD 50b mA GPIO28-45 VDD 50b mA SDX VDD 50b mA a b Recommended minimum. Actual power drawn is very dependent on use-case Each GPIO can supply up to 16mA, aggregate current per bank must not exceed 50mA Table 8: Mimimum Power Supply Requirements 8 Booting The eMMC Flash device on CM3+ is directly connected to the primary BCM2837 SD/eMMC interface. These connections are not accessible on the module pins. On CM3+ Lite this SD interface is available on the SDX pins. 14 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 When initially powered on, or after the RUN pin has been held low and then released, the BCM2837 will try to access the primary SD/eMMC interface. It will then look for a file called bootcode.bin on the primary partition (which must be FAT) to start booting the system. If it cannot access the SD/eMMC device or the boot code cannot be found, it will fall back to waiting for boot code to be written to it over USB; in other words, its USB port is in slave mode waiting to accept boot code from a suitable host. A USB boot tool is available on Github which allows a host PC running Linux to write the BCM2837 boot code over USB to the module. That boot code then runs and provides access to the SD/eMMC as a USB mass storage device, which can then be read and written using the host PC. Note that a Raspberry Pi can be used as the host machine. For those using Windows a precompiled and packeged tool is available. For more information see here. The Compute Module has a pin called EMMC DISABLE N which when shorted to GND will disable the SD/eMMC interface (by physically disconnecting the SD CMD pin), forcing BCM2837 to boot from USB. Note that when the eMMC is disabled in this way, it takes a couple of seconds from powering up for the processor to stop attempting to talk to the SD/eMMC device and fall back to booting from USB. Note that once booted over USB, BCM2837 needs to re-enable the SD/eMMC device (by releasing EMMC DISABLE N) to allow access to it as mass storage. It expects to be able to do this by driving the EMMC EN N 1V8 pin LOW, which at boot is initially an input with a pull up to 1V8. If an end user wishes to add the ability to access the SD/eMMC over USB in their product, similar circuitry to that used on the Compute Module IO Board to enable/disable the USB boot and SD/eMMC must be used; that is, EMMC DISABLE N pulled low via MOSFET(s) and released again by MOSFET, with the gate controlled by EMMC EN N 1V8. Ensure you use MOSFETs suitable for switching at 1.8V (i.e. use a device with gate threshold voltage, Vt, suitable for 1.8V switching). 9 9.1 Peripherals GPIO BCM2837 has in total 54 GPIO lines in 3 separate voltage banks. All GPIO pins have at least two alternative functions within the SoC. When not used for the alternate peripheral function, each GPIO pin may be set as an input (optionally as an interrupt) or an output. The alternate functions are usually peripheral I/Os, and most peripherals appear twice to allow flexibility on the choice of I/O voltage. GPIO bank2 is used on the module to connect to the eMMC device and for an on-board I2C bus (to talk to the core SMPS and control the special function pins). On CM3+ Lite most of bank2 is exposed to allow a user to connect their choice of SD card or eMMC device (if required). Bank0 and 1 GPIOs are available for general use. GPIO0 to GPIO27 are bank0 and GPIO28-45 make up bank1. GPIO0-27 VDD is the power supply for bank0 and GPIO28-45 VDD is the power supply for bank1. SDX VDD is the supply for bank2 on CM3+ Lite. These supplies can be in the range 1.8V-3.3V (see Table 7) and are not optional; each bank must be powered, even when none of the GPIOs for that bank are used. Note that the HDMI HPD N 1V8 and EMMC EN N 1V8 pins are 1.8V IO and are used for special functions (HDMI hot plug detect and boot control respectively). Please do not use these pins for any other purpose, as the software for the module will always expect these pins to have these special functions. If they are unused please leave them unconnected. 15 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 All GPIOs except GPIO28, 29, 44 and 45 have weak in-pad pull-ups or pull-downs enabled when the device is powered on. It is recommended to add off-chip pulls to GPIO28, 29, 44 and 45 to make sure they never float during power on and initial boot. 9.1.1 GPIO Alternate Functions GPIO Default Pull ALT0 ALT1 ALT2 ALT3 ALT4 ALT5 0 High SDA0 SA5 PCLK - - - 1 High SCL0 SA4 DE - - - 2 High SDA1 SA3 LCD VSYNC - - - 3 High SCL1 SA2 LCD HSYNC - - - 4 High GPCLK0 SA1 DPI D0 - - ARM TDI 5 High GPCLK1 SA0 DPI D1 - - ARM TDO 6 High GPCLK2 SOE N DPI D2 - - ARM RTCK 7 High SPI0 CE1 N SWE N DPI D3 - - - 8 High SPI0 CE0 N SD0 DPI D4 - - - 9 Low SPI0 MISO SD1 DPI D5 - - - 10 Low SPI0 MOSI SD2 DPI D6 - - - 11 Low SPI0 SCLK SD3 DPI D7 - - - 12 Low PWM0 SD4 DPI D8 - - ARM TMS 13 Low PWM1 SD5 DPI D9 - - ARM TCK 14 Low TXD0 SD6 DPI D10 - - TXD1 15 Low RXD0 SD7 DPI D11 - - RXD1 16 Low FL0 SD8 DPI D12 CTS0 SPI1 CE2 N CTS1 17 Low FL1 SD9 DPI D13 RTS0 SPI1 CE1 N RTS1 18 Low PCM CLK SD10 DPI D14 - SPI1 CE0 N PWM0 19 Low PCM FS SD11 DPI D15 - SPI1 MISO PWM1 20 Low PCM DIN SD12 DPI D16 - SPI1 MOSI GPCLK0 21 Low PCM DOUT SD13 DPI D17 - SPI1 SCLK GPCLK1 22 Low SD0 CLK SD14 DPI D18 SD1 CLK ARM TRST - 23 Low SD0 CMD SD15 DPI D19 SD1 CMD ARM RTCK - 24 Low SD0 DAT0 SD16 DPI D20 SD1 DAT0 ARM TDO - 25 Low SD0 DAT1 SD17 DPI D21 SD1 DAT1 ARM TCK - 26 Low SD0 DAT2 TE0 DPI D22 SD1 DAT2 ARM TDI - 27 Low SD0 DAT3 TE1 DPI D23 SD1 DAT3 ARM TMS - Table 9: GPIO Bank0 Alternate Functions 16 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 GPIO Default Pull ALT0 ALT1 ALT2 ALT3 ALT4 ALT5 28 None SDA0 SA5 PCM CLK FL0 - - 29 None SCL0 SA4 PCM FS FL1 - - 30 Low TE0 SA3 PCM DIN CTS0 - CTS1 31 Low FL0 SA2 PCM DOUT RTS0 - RTS1 32 Low GPCLK0 SA1 RING OCLK TXD0 - TXD1 33 Low FL1 SA0 TE1 RXD0 - RXD1 34 High GPCLK0 SOE N TE2 SD1 CLK - - 35 High SPI0 CE1 N SWE N - SD1 CMD - - 36 High SPI0 CE0 N SD0 TXD0 SD1 DAT0 - - 37 Low SPI0 MISO SD1 RXD0 SD1 DAT1 - - 38 Low SPI0 MOSI SD2 RTS0 SD1 DAT2 - - 39 Low SPI0 SCLK SD3 CTS0 SD1 DAT3 - - 40 Low PWM0 SD4 - SD1 DAT4 SPI2 MISO TXD1 41 Low PWM1 SD5 TE0 SD1 DAT5 SPI2 MOSI RXD1 42 Low GPCLK1 SD6 TE1 SD1 DAT6 SPI2 SCLK RTS1 43 Low GPCLK2 SD7 TE2 SD1 DAT7 SPI2 CE0 N CTS1 44 None GPCLK1 SDA0 SDA1 TE0 SPI2 CE1 N - 45 None PWM1 SCL0 SCL1 TE1 SPI2 CE2 N - Table 10: GPIO Bank1 Alternate Functions Table 9 and Table 10 detail the default pin pull state and available alternate GPIO functions. Most of these alternate peripheral functions are described in detail in the Broadcom Peripherals Specification document and have Linux drivers available. 9.1.2 Secondary Memory Interface (SMI) The SMI peripheral is an asynchronous NAND type bus supporting Intel mode80 type transfers at 8 or 16 bit widths and available in the ALT1 positions on GPIO banks 0 and 1 (see Table 9 and Table 10). It is not publicly documented in the Broadcom Peripherals Specification but a Linux driver is available in the Raspberry Pi Github Linux repository (bcm2835 smi.c in linux/drivers/misc). 9.1.3 Display Parallel Interface (DPI) A standard parallel RGB (DPI) interface is available on bank 0 GPIOs. This up-to-24-bit parallel interface can support a secondary display. Again this interface is not documented in the Broadcom Peripherals Specification but documentation can be found here. 17 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 9.1.4 SD/SDIO Interface The BCM283x supports two SD card interfaces, SD0 and SD1. The first (SD0) is a proprietary Broadcom controller that does not support SDIO and is the primary interface used to boot and talk to the eMMC or SDX x signals. The second interface (SD1) is standards compliant and can interface to SD, SDIO and eMMC devices; for example on a Raspberry Pi 3 B+ it is used to talk to the on-board CYW43455 WiFi device in SDIO mode. Both interfaces can support speeds up to 50MHz single ended (SD High Speed Mode). 9.2 CSI (MIPI Serial Camera) Currently the CSI interface is not openly documented and only CSI camera sensors supported by the official Raspberry Pi firmware will work with this interface. Supported sensors are the OmniVision OV5647 and Sony IMX219. It is recommended to attach other cameras via USB. 9.3 DSI (MIPI Serial Display) Currently the DSI interface is not openly documented and only DSI displays supported by the official Raspberry Pi firmware will work with this interface. Displays can also be added via the parallel DPI interface which is available as a GPIO alternate function - see Table 9 and Section 9.1.3 9.4 USB The BCM2837 USB port is On-The-Go (OTG) capable. If using either as a fixed slave or fixed master, please tie the USB OTGID pin to ground. The USB port (Pins USB DP and USB DM) must be routed as 90 ohm differential PCB traces. Note that the port is capable of being used as a true OTG port however there is no official documentation. Some users have had success making this work. 9.5 HDMI BCM283x supports HDMI V1.3a. It is recommended that users follow a similar arrangement to the Compute Module IO Board circuitry for HDMI output. The HDMI CK P/N (clock) and D0-D2 P/N (data) pins must each be routed as matched length 100 ohm differential PCB traces. It is also important to make sure that each differential pair is closely phase matched. Finally, keep HDMI traces well away from other noise sources and as short as possible. Failure to observe these design rules is likely to result in EMC failure. 18 Release 2 Compute Module 3+ Datasheet Copyright Raspberry Pi (Trading) Ltd. 2019 9.6 Composite (TV Out) The TVDAC pin can be used to output composite video (PAL or NTSC). Please route this signal away from noise sources and use a 75 ohm PCB trace. Note that the TV DAC is powered from the VDAC supply which must be a clean supply of 2.5-2.8V. It is recommended users generate this supply from 3V3 using a low noise LDO. If the TVDAC output is not used VDAC can be connected to 3V3, but it must be powered even if the TV-out functionality is unused. 10 Thermals The BCM2837 SoC employs DVFS (Dynamic Voltage and Frequency Scaling) on the core voltage. When the processor is idle (low CPU utilisation), it will reduce the core frequency and voltage to reduce current draw and heat output. When the core utilisation exceeds a certain threshold the core votlage is increased and the core frequency is boosted to the maximum working frerquency of 1.2GHz. The voltage and frequency are throttled back when the CPU load reduces back to an 'idle' level OR when the silicon temperature as mesured by the on-chip temperature sensor exceeds 80C (thermal throttling). A designer must pay careful attention to the thermal design of products using the CM3+ so that performance is not artificially curtailed due to the processor thermal throttling, as the Quad ARM complex in the BCM2837 can generate significant heat output under load. 10.1 Temperature Range The operating temperature range of the module is set by the lowest maximum and highest minimum of any of the components used. The eMMC and LPDDR2 have the narrowest range, these are rated for -25 to +80 degrees Celsius. Therefore the nominal range for the CM3+ and CM3+ Lite is -25C to +80C. However, this range is the maximum for the silicon die; therefore, users would have to take into account the heat generated when in use and make sure this does not cause the temperature to exceed 80 degrees Celsius. 11 Availability Raspberry Pi guarantee availability of CM3+ and CM3+ Lite until at least January 2026. 12 Support For support please see the hardware documentation section of the Raspberry Pi website and post questions to the Raspberry Pi forum. 19 Release 2