AT91SAM7L Technical Overview

Outlines

 Introduction  Power Supply Considerations  Clock Considerations  Supply Controller  Peripherals  Memory Mapping / Boot  AT91SAM7L-EK  AT91SAM7L-STK ARM-Based Products Group 2

AT91SAM7L Introduction

Low-Power Applications

 Static and dynamic power consumption lowered to a minimum  Performance scaling allows consuming only when required  Backup while entering sleep modes  Reduced number of external devices simplifies the designs  In many low-power applications, operating from 1.8V to 3.6V, the MCU is in sleep mode for the majority of the time, waking up periodically to an event 4 ARM-Based Products Group

Low-Power Applications

 Need an MCU with  Short wake-up time to guarantee fast response time to events  Flexible clock management  Increased number of low power modes  Segment LCD is often expected as User Interface ARM-Based Products Group 5

AT91SAM7L Featured for Low Power

 Enable portable devices to derive power from a dual-cell battery providing a

true dual-cell battery system solution

 Capable of

operating down to 1.8V

 Use

innovative design techniques

 To deliver a typical

OFF-mode

current of

100nA

typical WAIT mode current of 9µA  To enable integration resulting in fewer external components and reduced BOM cost  and a To

Wake-up

from its low power WAIT-mode with the CPU operating at 2MHz within just

6µs

 To save battery life in efficient architecture ACTIVE-mode current as low as

0.5mA/MHz active mode

thanks to power ARM-Based Products Group 6

AT91SAM7L provides longer battery life and lower overall system cost in dual-cell modes!

Innovative Design Techniques

 Sub 0.18µm technology for high performance and low dynamic power consumption  Power switching  Voltage scaling  Clock switching  Cell libraries, Zero POR, BOD and Voltage Regulator designed for minimum leakage current ARM-Based Products Group 8

AT91SAM7L Applications

 Well-suited for products powered by user replaceable batteries such as:             Calculator/translator ZigBee and Wireless modules Medical/Healthcare/Fitness Remote Control Toys Audio players PDA, GPS,voice recorders Watches Sensors PC Wireless peripherals House control Mobile Accessories ARM-Based Products Group 9

AT91SAM7L Block Diagram

JTAG Boundary Scan JTAG ICE

System Peripherals

AIC 1.8V

Voltage Regulator PIOA/B/C

PDC

DBGU LCD Voltage Regulator LCD Charge Pump WDT PIT RC OSC 2MHz PLL BOD POR RSTC PMC RTC RC OSC 32kHz Supply Contr XTAL 32kHz

Backup Unit

APB ARM7TDMI SRAM 2KB (Backup) 4KB (Core) Flash 64-128kB AMBA System Bus Peripheral Bridge

PDC

ADC x4 PWM x4 I/O x80 16-bit Timer x3

PDC

USART

PDC

USART

User Peripherals

PDC

SPI ROM

IAP FFPI SAM-BA Boot PDC

TWI Segment LCD Controller 40 segments X 10 Terminals Peripheral DMA Controller: 11 channels

ARM-Based Products Group 10

Microcontrollers AT91SAM7L64 AT91SAM7L128 Package QFP128 BGA144 Key Features PCK-MCK 37MHz Single Supply Power On Reset Dual Internal RC Programmable Brownout I/O 1.8V or 3.3V

Security Bit

AT91SAM7L Performance

 Low power design with the right performance  Maximum operating frequency - Industrial worst case, 3.0V: 37 MHz - Industrial worst case, 1.8V: 30 MHz  128-bit Flash Access - Single cycle random Flash access up to 17MHz - Zero wait state Flash in sequential accesses - Page Programming time 4.6ms max (auto-erase included)  Peripheral DMA controller unlocks processor performance for the application 11 ARM-Based Products Group

AT91SAM7L Power Supply Considerations

Power Supplies

 Seven types of power supply pins 

VDDIO1 pin

- Main regulator Input, Power all the PIOC I/O lines: 1.8V-3.6V



VDDOUT pin

 - Main regulator Output: 1.35V-1.8V

VDDCORE pin

- Power the logic, the PLL, the Fast RC Osc, ADC and Flash: 1.35V 1.8V



VDDLCD pin

- LCD regulator Input. Voltage ranges 2.5V-3.6V.

 

VDDIO2 pin

- LCD regulator output. Power LCD and PIOA and PIOB I/O lines

VDDINLCD pin

- Charge pump Input: 1.8V-3.6V



VDD3V6 pin

- Charge pump Output: 3.6V

ARM-Based Products Group 13

Single Power Supply System

 Directly powered from batteries  Usage of the embedded charge pump and LCD voltage regulator ARM-Based Products Group 14

LCD Voltage Regulator Externally Supplied

 Saving Charge Pump power consumption  250µA on VDDINLCD and 50µA on VDDIO1 ARM-Based Products Group 15

LCD Driver Externally Supplied

 Saving Charge Pump and LCD Voltage Regulator power consumption   250µA on VDDINLCD and 50µA on VDDIO1 30µA on VDDLCD ARM-Based Products Group 16

LCD Not Used

 VDDLCD must be powered due to design constraint ARM-Based Products Group 17

Main Voltage regulator

 Features 3 different operating modes:    Normal mode: less than 30 µA static and draws 60 mA Deep mode: less than 8.5 µA static and draw up to 1 mA Shutdown mode: less than 1 µA   Programmable Ouput Voltage  Caution: VDDCORE cannot be powered by an external voltage regulator is not allowed whereas it was possible in previous SAM7 devices

1.8V 1.55V

In Deep and Normal modes only

to 3.6V Scalable Voltage Regulator to 1.8V

 4 steps from 1.55V to 1.80V

 Reading the Flash at 1.55V

 MCK maximum frequency is 25 MHz

DEEP SHDW VRVDD

ARM-Based Products Group 18

Reset Controller

 Zero-power Power-On Reset allows Supply Controller to start properly   POR threshold voltage rising is 2.2V on VDDIO1 POR threshold voltage falling is 1.8V on VDDIO1 Need a voltage battery higher than 2.2V at start up  NRSTB is an ASYNCHRONOUS Reset pin    Active in all power modes Acts exactly as the zero-power power-on reset When asserted low, the supply controller is reset and the system parts are powered off ARM-Based Products Group 19

Brown Out Detector

 Monitors VDDIO1  Disabled by default (to be enabled by software)  Programmable threshold  From 1.9V to 3.4V with 100mV steps  Generate either a Reset of the core or a wake-up of the core power supply  “Switched” mode:  Periodic checks of VDDIO1 reduce BOD current consumption down to 2µA - Every 32, 256 or 2048 SLCK periods ARM-Based Products Group 20

AT91SAM7L Clock Considerations

Saving Power with Clock Flexibility

 Many designers equate low power to slow clock frequencies  However depending on what the MCU is doing and what low power mode are available on the MCU, running at maximum speed can actually save power  Need an MCU with flexible clocks!

ARM-Based Products Group 22

Clock Sources

 Slow Clock – SLCK  On-chip 32KHz RC oscillator (20KHz-44KHz)   Xtal 32KHz oscillator featuring bypass mode Selection is made through XTALSEL bit in SUPC_CR  Main Clock – MAINCK  On-chip 2MHz RC oscillator (1.35MHz-2.65MHz)  External clock on CLKIN pin up to 32MHz  Selection is made through MCKSEL bit in CKGR_MOR  PLL Clock – PLLCK   Input frequency: SLCK Output frequency: 18 to 47MHz  PLL fast startup to reach 70% of its target frequency in less than 60µs ARM-Based Products Group 23

Reset State

 On-chip 32KHz RC oscillator is enabled and selected as being SLCK  Xtal 32KHz oscillator is powered and disabled  On-chip 2MHz RC oscillator is enabled and selected as being MAINCK  PLL is disabled  The Processor and the Master Clock selection is the on-chip 2MHz RC oscillator 24 ARM-Based Products Group

Clock Management Diagram

PLLRC external filter Crystal 32KHz or Ext clock on XIN XIN XOUT Ext. Clk up to 32MHz CLKIN On-Chip 32KHz RC Osc.

Crystal Osc.

In: SLCK (32KHz) Out: 18MHz - 47MHz

20-44kHz

XTALSEL PLL SLCK MCK_SEL

Ext 44KHz max

MAINCK

Select the master clock

CSS PLLCK Prescaler

1..64 Step: power of 2 IDLE mode support

CPU On/Off PCK

PCK max 37MHz

MCK Periph Clk On/Off Peripherals CLOCKS On-Chip 2MHz RC Osc.

PLLCK SLCK MAINCK Prescaler

1..64 Step: power of 2

pck[0:2]

Programmable clock 25 ARM-Based Products Group

Clock Management Diagram

PLLRC external filter Crystal 32KHz or Ext clock on XIN XIN XOUT Ext. Clk up to 37MHz CLKIN On-Chip 32KHz RC Osc.

20-44kHz

XTALSEL Crystal Osc.

On-Chip 2MHz RC Osc.

In: SLCK (32KHz) Out: 18MHz - 47MHz PLL SLCK

Select the master clock

CSS PLLCK At Reset Prescaler

1 ..64 Step: power of 2 IDLE mode support

CPU On/Off PCK

PCK max 37MHz

MCK Periph Clk On/Off Peripherals CLOCKS MCK_SEL

Ext 44KHz max

MAINCK PLLCK SLCK MAINCK At Reset Prescaler

1..64 Step: power of 2

pck[0:2]

Programmable clock 26 ARM-Based Products Group

What about accuracy?

 Both on-chip RC oscillators do not provide good accuracy   On-chip 32KHz RC oscillator (20KHz-44KHz) On-chip 2MHz RC oscillator (1.35MHz-2.65MHz)  For applications requiring better accuracy    Xtal 32KHz oscillator or external 32KHz clock signal External clock signal on XIN Auto calibration by software using an external signal - DBGU in SAM-BA Boot ARM-Based Products Group 27

Startup Time – OFF MODE

Power-On & Low level on FWUP 800µs max.

30 SLCK cycles 1ms max.

430µs max.

POR Startup 2 MAINCK cycles 1µs max.

FWUP Debouncing Voltage Regulator + 1 SLCK cycle 2,2ms max.

Power-on to First-Instruction CPU Startup First Instruction Fetched

28 ARM-Based Products Group

Wake-up Time – Backup MODE

Wake-Up Sources 430µs max.

Voltage Regulator + 1 SLCK cycle 5µs max.

2MHz RC Startup 440µs max.

2 MAINCK cycles 1µs max.

CPU Startup First Instruction Fetched

ARM-Based Products Group 29

Wake-up Time – Wait MODE

Voltage Regulator in deep or normal mode Wake-Up Sources 5µs max.

2 MAINCK cycles 1µs max.

2MHz RC Startup 6µs max.

CPU Startup Next Instruction Fetched Voltage Regulator in deep or normal mode

ARM-Based Products Group 30

What’s new?

 First SAM7 device with Xtal 32KHz oscillator including bypass mode support  Fast on-chip 2MHz RC oscillator  After reset, the Main Clock derives from the on-chip 2MHz RC oscillator 31 ARM-Based Products Group

AT91SAM7L Supply Controller

Remove power from the chip?

 MCU's are moving into smaller geometries to reduce die size, which results in transistors that cannot tolerate direct application of 3 or more volts. So, voltage regulators are used to drop the voltage to the internal logic  Unfortunately, these regulators add to the MCU's current draw.  Removing power requires a more expensive toggle switch to disable power-up to the chip 33 ARM-Based Products Group

AT91SAM7L Power Control

1.8V to 3.6V

VDDINLCD VDD3V6 VDDLCD VDDIO2 VDDIO1 VDDOUT VDDCORE VDDIO1 32kHz RC Osc 32kHz Crystal Osc POR BOD Power Supply Controller Charge Pump LCD Regulator Scalable Main Voltage Regulator

VDDIO1

SRAM 2KB(backup) RTC

VDDIO2

LCD Controller

ARM7TDMI Memory Controller SRAM 4KB Peripherals Fast RC Osc

FLASH

VDDCORE

ARM-Based Products Group 34

Low Power Modes

  Backup Mode  Power consumption 3µA typ   Backup SRAM and RTC are optional in this mode Various wake-up sources  Wait Mode    Power consumption 9 µA typ Fast wake up time of 6µs (maximum) Wake-up from where the code has been stopped  OFF Mode  Power consumption 100nA typ  Real OFF-mode  Use of a push button instead of a regular switch  Tie FWUP pin low when OFF mode is not used Idle Mode   Same mode as all SAM7 components: PCK is Off Wake-up by interrupt ARM-Based Products Group 35

Wake-up 6µs Sleep 2µs Wait Mode

VReg out = 1.35V

PMC out = 0Hz Backup SRAM ON RTC ON LCD OFF Flash OFF

OFF Mode (Entry State) Wake-up 5ms Sleep 60µs Active Mode

VReg out = 1.8V

PMC out = 2MHz Processor clock on Backup SRAM ON

Wake-up 500µs Sleep 60µs Backup Mode

VReg OFF PMC OFF Backup SRAM ON RTC ON LCD OFF ARM-Based Products Group

Wake up > 1ms Idle Mode

VReg out = 1.35V

PMC out = 500Hz Processor clock off Backup SRAM ON RTC ON LCD OFF 36

AT91SAM7L Peripherals

 Wide range of on-chip peripherals  SPI, USART, I²C, Timer Counters, PWM, I/Os, RTC, ADC and Segment LCD Controller  No USB Device Port  No SSC (I2S)  No High-current drive pads (16mA) ARM-Based Products Group 38

SLCD Controller

 Up to 40 segments and 10 Commons  Support Static, 1/2, 1/3, 1/4, 1/5, 1/6, 1/7, 1/8, 1/9 & 1/10 duty  Support Static, 1/2, 1/3 and 1/4 bias  LCD regulator Output Voltage (Contrast) Software Selectable between 2.4 and 3.4V (16 steps)  Flexible selection of frame frequency (from Slow Clock)  Display Data Latch (Full freedom in Memory Register update)  Not needed Segment and Common pins can be used as I/Os  Programmable Buffer Driving Time (Up to 100% of the time) ARM-Based Products Group 39

Real Time Clock

 Continuously clocked by SLCK  Complete time-of-day clock with alarm and a two-hundred-year Gregorian calendar  Time and calendar values are coded in binary coded decimal (BCD) format  Time format can be 24-hour mode or 12-hour mode with an AM/PM indicator  Five programmable alarm fields: month, date, hours, minutes and seconds 40 ARM-Based Products Group

I/Os

 80 IOs : PIOA, PIOB and PIOC  Schmitt triggers on all inputs  IOs are not 5V tolerant  Maximum frequency   PIOC PIOA, PIOB : 37MHz @3V, 20MHz @1V8 (max) : 36MHz @3V, 20MHz @1V8 (max)  PIOC5 to PIOC8 drive 4mA  All other I/Os drive 2mA ARM-Based Products Group 41

AT91SAM7L Memory Mapping / Boot

Memory Mapping

 Common peripherals between SAM7S/X/SE and SAM7L have same user interface addresses  The split 6 Kbytes of SRAM (4KB Core + 2KB Backup) are seen contiguously at address: @ 0x002F F000

0x0020 0000 SRAM Core 4KB SRAM Backup 2KB 1MB 1MB 0x003F FFFF

ARM-Based Products Group 43

BootROM Memory

 Contains 3 applications:  SAM-BA Boot - Provides In-System Programming Solutions through serial communication channels  Fast Flash Programming Interface (FFPI) - Provides Production Programming Solutions using gang programmers  IAP Function: In Application Programming Function located in ROM, that can be called by any software application

Executed from ROM, allows FLASH programming by code running in FLASH Takes one argument in parameter : the command to be sent to the EFC Send the desired FLASH command to the EFC and waits for the FLASH to be ready

No external Crystal needed ARM-Based Products Group 44

Boot Solutions

GPNVM1 = 0 GPNVM1 = 1

ARM-Based Products Group 45

PC0=PC1=1

FFPI

Yes Yes

Boot Solutions

Power Up No

TST = 1

No

GPNVM1 = 1

Yes

Boot From ROM SAM-BA Boot Boot From Flash User Application 46 ARM-Based Products Group

No

Boot Solutions

Yes

GPNVM1 = 1

Boot From ROM: SAM-BA Boot

Flash @: 0x0010_0000 ROM @: 0x0000_0000

(and 0x0040_0000)

Boot From FLASH: User Application

Flash @: 0x0000_0000

(and 0x0010_0000)

ROM @: 0x0040_0000

Set GPNVM1 to boot from Flash after reset

Power Up

Clear GPNVM1 to boot from ROM after reset

Power Up

ARM-Based Products Group 47

AT91SAM7L-EK

For seminars and training only!

AT91SAM7L-EK

 One handheld board       One 400-segment LCD Display One 35-key Keyboard (7x5 matrix) Two AAA battery clip socket IrDA transceiver Weather Station (Temperature/Pressure sensor) SPI DataFlash® SD/MMC Card connector  ZIGBEE expansion connector (optional RZ502 board)     One VCC battery input monitor One Force Wake-up push button One Reset push button Configuration Jumpers ARM-Based Products Group 49

AT91SAM7L-EK

 One docking board   5-Volt DC power supply input One Yellow Power Supply LED (software controlled)    Two Green User LEDs One JTAG/ICE interface One HE10 ADC connector (4 inputs)  Three expansion connectors (PIOA, PIOB, PIOC) ARM-Based Products Group 50

AT91SAM7L-STK

Official AT91SAM7L Starter Kit available for customers!

AT91SAM7L-STK

 Low cost version      One 400-segment LCD Display Two AAA battery clip socket One JTAG/ICE interface ZIGBEE expansion connector One expansion connectors (PIOC)  One Force Wake-up push button   One Reset push button Four User push buttons ARM-Based Products Group 52

AT91SAM7L Key Selling Features

 Directly Supplied by batteries  Embeds a 30MIPS processor with a 6KBytes SRAM and a 64KBytes or 128KBytes Flash  2Kbytes Backup SRAM + RTC for a few µA  Offers a wide range of operating modes  Guarantees µsec-range wake-up time  Embeds a wide range of peripherals  SPI, USART, I²C, Timer Counters, PWM, I/Os, ADC  Embeds a 40x10 Segment LCD Controller  On-chip voltage regulator and contrast control  2 packages options  QFP128 or BGA144 53 ARM-Based Products Group