Operating Modes, Current Consumption and Timings for SX8722

Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
SX8722 operating modes
Current consumption and timings
Technical note TN8722.01
© 2007 Semtech Corp.
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1
Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
Table of Contents
1
1.1
1.2
1.3
2
2.1
2.2
2.2.1
2.2.2
2.2.3
2.2.4
2.2.5
2.3
2.3.1
2.3.2
2.3.3
3
3.1
3.2
3.2.1
3.2.2
3.2.3
3.2.4
3.2.5
3.3
3.3.1
3.3.2
3.3.3
3.3.4
4
4.1
4.2
4.2.1
4.2.2
4.2.3
4.2.4
4.2.5
4.3
4.3.1
4.3.2
4.3.3
4.3.4
4.3.5
5
5.1
5.2
5.3
5.4
6
7
7.1
Introduction ..................................................................................................................... 4
What is SX8722?.....................................................................................................................4
Documentation about the SX8722 ...........................................................................................4
SX8722 state diagram .............................................................................................................5
Active mode..................................................................................................................... 7
Description ..............................................................................................................................7
Operating specifications ..........................................................................................................7
Pin activity ...........................................................................................................................7
External 32k Xtal..................................................................................................................7
Internal voltage multiplier enabled below 3V VDD.................................................................7
2
I C communication ...............................................................................................................7
SX8722 current consumption ...............................................................................................8
How to set SX8722 in active mode ........................................................................................ 10
Start-up.............................................................................................................................. 10
From Sleep mode .............................................................................................................. 10
From Shutdown mode ........................................................................................................ 10
Sleep mode .................................................................................................................... 11
Description ............................................................................................................................ 11
Operating specifications of the sleep mode ............................................................................ 11
Summary ........................................................................................................................... 11
SX8722 sleep current consumption below 3V Vbat............................................................. 11
SX8722 sleep current consumption with the 32.768 kHz Xtal.............................................. 12
SX8722 sleep current consumption without the 32.768 KHz Xtal ........................................ 12
Current consumption measurements results....................................................................... 13
How to set SX8722 in sleep mode ......................................................................................... 14
2
I C sleep ............................................................................................................................ 14
SLEEP pin ......................................................................................................................... 14
Is SX8722 in SLEEP mode?............................................................................................... 14
Wake up from sleep mode to active mode .......................................................................... 15
Shutdown mode ............................................................................................................ 16
Description ............................................................................................................................ 16
Operating specifications in shutdown mode ........................................................................... 16
Summary ........................................................................................................................... 16
Internal voltage multiplier ................................................................................................... 16
Shutdown mode current consumption ................................................................................ 16
Current consumption measurements results....................................................................... 16
How to set shutdown mode consumption around 0.5µA...................................................... 17
How to set SX8722 in shutdown mode................................................................................... 18
2
I C Shutdown command..................................................................................................... 18
2
I C SHUT bit toggle ............................................................................................................ 18
SHUT pin ........................................................................................................................... 19
Wake-up from shutdown mode to active mode ................................................................... 19
Change from shutdown mode to sleep mode...................................................................... 19
Time specifications ....................................................................................................... 20
Time specification without the 32.768 kHz Xtal ...................................................................... 20
Start-up time with the 32.768 kHz Xtal presence .................................................................... 20
Changing mode by pin signal................................................................................................. 20
2
Changing mode by I C command .......................................................................................... 21
ANNEXE ......................................................................................................................... 22
TAPE & REEL SPECIFICATION..................................................................................... 23
MLP/QFN (0.70mm - 0.90mm package thickness) ................................................................. 23
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Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
Table of Figures
Figure 1: SX8722 mode state diagram ........................................................................................ 5
Figure 2: pull-up resistor on I2C wire............................................................................................ 8
Figure 3: acquisition chain........................................................................................................... 9
Figure 4: I2C sequence to set in sleep mode............................................................................. 14
Figure 5: I2C sequence to wake up from sleep mode ................................................................ 14
Figure 6: I2C command to set in shutdown mode ...................................................................... 18
Figure 7: I2C sequence to set in shutdown mode ...................................................................... 18
Figure 8: start-up timing diagram with EEPROM loading ........................................................... 20
Figure 9: Direction of feed ......................................................................................................... 23
Figure 10: Tape and reel ........................................................................................................... 23
Table of Tables
Table 1:
Table 2:
Table 3:
Table 4:
Table 5:
Table 6:
Table 7:
PGA current consumption in [µA]................................................................................... 8
sleep mode current consumption ................................................................................. 13
shutdown mode current consumption .......................................................................... 16
changing mode timings by pin setting .......................................................................... 20
2
changing mode timings by I C command ..................................................................... 21
average current measurements ................................................................................... 22
Tape and reel dimensions ........................................................................................... 23
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Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
1 Introduction
This document is provided to you as a complement to the datasheet. It is a guideline to set up
SX8722 in its different operating modes and sums up the corresponding current consumptions and
timings.
It is recommended to go though the datasheet first so as to have a detail description of SX8722
1.1 What is SX8722?
SX8722 main function is analog signal acquisition from Wheatstone bridges or single ended sensors.
The input can be a pressure sensor, a GMR or AMR magnetic sensor, a chemical sensor, a
thermistor or a mix of several of these sensors.
2
SX8722 Sensor interface is totally configurable through an I C compatible interface. Several
parameters are configurable through this interface such as alarms or signal post processing.
SX8722 has three operating modes:
• active mode
• sleep mode
• shutdown mode
The different modes are controlled by the embedded program and these are described in this
document.
1.2 Documentation about the SX8722
The following documents about SX8722 and the tools are also available:
• SX8722 Datasheet
• SX8722 Errata
• XE8000EV120 Users Guide
• XE8000EV120 Interfacing your first pressure sensor
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Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
1.3 SX8722 state diagram
LOW POWER
shutdown
mode
- Reset
- Power on reset
sleep
mode
- SHUT pin signal
2
- I C SHUTDOWN command
- I2C SHUT bit toggle
- Reset
- sleep pin signal
- I2C SLEEP bit toggle
- Power on reset
start-up
from sleep
sleep
sequence
ACTIVE
start-up
from shut
shutdown
sequence
- SLEEP pin signal
- I2C SLEEP bit toggle
active
mode
Figure 1: SX8722 mode state diagram
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- SHUTDOWN pin signal
- I2C SHUTDOWN command
- I2C SHUT bit toggle
Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
The transition states:
Start-up from shutdown:
- Initializes the SX8722
- Load EEPROM if present
- Restores EEPROM configuration and set the SX8722
Start-up from sleep:
- Restores the RC active value
- Enables VLD
- Restores SX8722 configuration saved in RAM
Sleep sequence:
- Waits for I C STOP sequence
- Stops the ADC
- Disable VLD
- Bias current off
- Set the clock to RC minimum value or to Xtal if present
- asm “HALT”
Shutdown sequence:
- Waits for I2C STOP sequence
- Stops the ADC
- Disable VLD
- Bias current off
- Stops the SX8722
2
The timing of the transition states depends mainly on the Xtal presence, the EEPROM presence and
2
if the transition is caused by an I C command or by a pin signal (SLEEP, SHUT, RESET).
See time specification chapter in this document and SX8722 datasheet for more information.
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Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
2 Active mode
In this chapter you will find:
• The description of the active mode
• The operating specifications
• How to set SX8722 in active mode
2.1 Description
In active mode, SX8722 and all its peripherals can work and execute the embedded program. The
acquisition chain, the alarms and the signal post processing can be activated and parameterized.
2.2 Operating specifications
2.2.1 Pin activity
SX8722 generates pulses on the pin READY in active mode.
At 1.8 MHz RC with the external 32.768 kHz Xtal, a pulse of 3µs occurs every 36ms..
The READY pin generates a single signal used to interrupt the host microcontroller when a new
sample value is available on SX8722 output register.
This signal can be used to verify that SX8722 is in active mode.
2.2.2 External 32k Xtal
If there is no external Xtal and if no calibration is needed, the CAL pin must be connected to Vss
for SX8722 to operate.
If there is an external Xtal, the CAL pin must be connected to Vbat.
2.2.3 Internal voltage multiplier enabled below 3V VDD
An internal voltage multiplier (VMULT) is automatically enabled when the power supply goes below
TM
3 Volts to power the ZoomingADC , and this internal voltage multiplier requires an external
capacitor from the VMULT pin to the ground. The value of this capacitor must be between 1 and
3nF.
2.2.4 I2C communication
2
10kΩ pull up resistors are necessary on SCL and SDA as mentioned in the I C protocol
specification. Pull-up resistors on EE_SDA and EE_SCL pins are necessary for EEPROM
communication too.
The SDA and SCL IO are open collectors when waiting for communication.
EE_SDA and EE_SCL are grounded. In this case SX8722 is the master and these signals are
active only at start-up to load a configuration or when a SAVE/LOAD EEPROM command is
received by the SX8722.
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Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
The EEPROM is powered by the EE_POWER pin of SX8722 only
VBAT
10 kΩ pull up
resistors
SX8722
VBAT
VBAT
CAL
EE_POWER
10 kΩ pull up
resistors
Supply
I2C Slave
EEPROM
I2C Slave
SDA
I2C Master
I2C Master
EE_SCL
VREG
EE_SDA
VMULT
BIAS
SDA
Port In
READY
SCL
SDA
SCL
SCL
Host µC
GND
GND
1µF
2nF
2
Figure 2: pull-up resistor on I C wire
2.2.5 SX8722 current consumption
SX8722 mean current consumption in active mode is around 200 [µA], without enabled PGA. The
value of the gain of de PGA can have a negligible influence on consumption in active mode.
Additional consumption depends on the active PGA and on the bias current parameter.
bias 25%
bias 50%
bias 75%
bias 100%
IPGA1
[µA]
50
95
140
185
IPGA2
[µA]
40
75
110
145
IPGA3
[µA]
50
98
145
190
Table 1: PGA current consumption in [µA]
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Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
fS
AC
MUX
Inputs
0
1
2
3
4
5
6
7
fS
PGA1
PGA2
0
1
2
3
MUX
Off. 2
AR
PRELIMINARY
PGA3
Off. 3
V REF
Figure 3: acquisition chain
2.2.5.1 Example 1
Bias current: 25%
PGA1: enabled
PGA2: enabled
PGA3: enabled
SX8722 measured current consumption: ~330 µA
2.2.5.2 Example 2
Bias current: 100%
PGA1: enabled
PGA2: enabled
PGA3: enabled
SX8722 measured current consumption: ~710 µA
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ADC
Measurement engine
Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
2.3 How to set SX8722 in active mode
2.3.1 Start-up
At start-up SX8722 is automatically set in active mode.
If there is no EEPROM configuration loaded at start-up, PGA are not active.
2.3.2 From Sleep mode
•
•
•
•
Positive pulse on RESET pin
Negative pulse on the SLEEP pin
2
SLEEP bit toggle in the SXCtrl1 register (I C write mask command)
Other interruption
2.3.3 From Shutdown mode
•
•
Positive pulse on RESET pin
Power-on-reset (negative pulse on VBAT pin)
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PRELIMINARY
Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
3 Sleep mode
In this chapter you will find:
• The description of the sleep mode
• The operating specifications in sleep mode
• How to set SX8722 in sleep mode
3.1 Description
2
The sleep mode is a low power mode. It can be called by an I C sequence or by sending a
negative pulse to SX8722 SLEEP pin.
3.2 Operating specifications of the sleep mode
3.2.1 Summary
•
•
•
•
•
•
•
SX8722 configuration saved in RAM
ADC stopped
VLD stopped (voltage level detector)
If Xtal present, clock set to Xtal 32k
If Xtal not present, clock set to RC minimum value (~80kHz)
Bias current off
2
Program HALT, SX8722 needs an interrupt to wake up (I C communication, SLEEP pin
signal, reset, etc).
3.2.2 SX8722 sleep current consumption below 3V Vbat
Below 3 Volts SX8722 enables the internal voltage multiplier to power the ZoomingADC™.
This internal voltage multiplier is automatically enabled when the power supply goes below 3V
Vbat.
This voltage multiplier increases SX8722 consumption. This is why the chip consumption in
sleep mode with 2.5V supply is higher than with 5.5V supply.
There is a possibility to consume less current when the Vbat voltage is lower than 3V: the
SLEEP signal has to be sent to the SLEEP pin when Vbat is higher than 3V, and then
decrease the Vbat value. In this case, the voltage multiplier is not activated.
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Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
3.2.3 SX8722 sleep current consumption with the 32.768 kHz Xtal
The sleep mode current consumption with the presence of the 32.768 kHz Xtal is around 1µA
if the supply voltage is above 3V. Below 3V, the current consumption is around 4 µA because
the VMULT is enabled.
In addition to set the precise RC frequency, the presence of an external 32.768 kHz Xtal
allows SX8722 sleep current consumption 3x lower than without the Xtal.
In this case SX8722 main clock is generated by the Xtal.
3.2.4 SX8722 sleep current consumption without the 32.768 KHz Xtal
The current consumption in sleep mode without the 32.768 kHz Xtal is around 3 µA if the
supply voltage is above 3V. Below 3V, the current consumption is around 9 µA because the
voltage multiplier is enabled. The RC min frequency is set and its value is around 80 kHz.
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Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
3.2.5 Current consumption measurements results
Vbat [V]
2.5
5.5
Temp. [°C]
-40
25
85
ISLEEP [µA]
7.69
8.792
9.536
ISLEEP [µA]
2.69
2.844
2.976
(1)
ISLEEP [µA] with Xtal
3.028
3.864
4.362
-40
25
85
2.84
3.024
3.196
6.58
7.538
8.146
0.998
1.074
1.292
ISLEEP [µA] with Xtal
0.988
1.062
1.264
3.28
4.158
4.426
Table 2: sleep mode current consumption
(1) Indirect measurement: the SLEEP signal is sent on SLEEP pin, and then the Vbat voltage
is changed. The 5.5V orange cases have not real application. The voltage multiplier is forced
on.
As indicated in the table, the sleep mode current consumption is around 3 times lower with a
Xtal presence.
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(1)
Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
3.3 How to set SX8722 in sleep mode
3.3.1 I2C sleep
Through the I2C interface, send a write mask command at address 00 and toggle the SLEEP
bit of the SXCtrl1 register.
I2C SEQUENCE:
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
1
0
0
0
ACK
0
STOP
0
ACK
0
Mask
0x04
ACK
1
ACK
0
R/W
1
START
0
Data
0x04
Memory address
0x00
Command
0x20
ACK
Slave address
0x48
Figure 4: I2C sequence to set in sleep mode
When SX8722 is in sleep mode, send a write mask command at address 00 and toggle the
SLEEP bit to restore SX8722 active mode.
I2C SEQUENCE:
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
ACK
0
Figure 5: I2C sequence to wake up from sleep mode
2
WARNING: The I C SLEEP command does not allow reaching as low current
consumption as the SLEEP pin command or writing the SXCtrl1 register SLEEP bit.
The sleep mode called by I2C SLEEP command (0x40) has a current consumption
around 80µA.
3.3.2 SLEEP pin
Put the SLEEP input signal to VSS, the SLEEP input is active on negative edge.
3.3.3 Is SX8722 in SLEEP mode?
There are pulses on the READY pin in active mode every 36ms. In sleep mode there is no
pulse on the READY pin.
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STOP
0
ACK
1
Mask
0x04
ACK
0
ACK
1
R/W
START
0
Data
0x00
Memory address
0x00
Command
0x20
ACK
Slave address
0x48
Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
3.3.4 Wake up from sleep mode to active mode
In sleep mode the internal program is in “HALT” assembler equivalent mode. The SLEEP
bit toggling in SXCtrl1 or a signal on the SLEEP pin can wake up the SX8722.
See active mode section for more information.
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Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
4 Shutdown mode
In this chapter you will find:
• The description of the shutdown mode
• The operating specifications
• How to set SX8722 in shutdown mode
4.1 Description
This is a very low-power mode because all circuit clocks and all peripherals are stopped. Only
some service blocks remain active.
4.2 Operating specifications in shutdown mode
4.2.1 Summary
•
•
•
•
•
•
•
ADC stopped
VLD stopped
If Xtal present, clock set to Xtal 32k
If Xtal not present, clock set to RC minimum value (~80kHz)
Bias current off
Program HALT, interrupt off
2
No possible I C communication.
4.2.2 Internal voltage multiplier
Like in sleep mode, internal voltage multiplier is automatically enabled when the power supply
goes below 3 Volts but the internal voltage multiplier requires an external capacitor between
VMULT pin and Vss, the value of this capacitor must be between 1 and 3nF.
4.2.3 Shutdown mode current consumption
The current consumption in shutdown mode is around 0.5 µA if the supply voltage is above
3V. Below 3V, the current consumption is around 3.5 µA because the voltage multiplier is
enabled.
4.2.4 Current consumption measurements results
voltage [V] temperature [°C]
-40
2.5
25
85
5.5
-40
25
85
(1)
ISHUT [µA]
2.6
3.478
3.628
ISHUT [µA]
0.492
0.53
0.69
0.5
0.54
0.73
2.85
3.63
3.538
Table 3: shutdown mode current consumption
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Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
(1) Indirect measurement: at first, the signal command is set on the SHUTDOWN pin, and then
the supply voltage is changed, from 5.5V to 2.5V or from 2.5V to 5.5V.
The 5.5V orange cases have not real application. The voltage multiplier is forced on.
4.2.5 How to set shutdown mode consumption around 0.5µA
By default, with a supply voltage below 3V the shutdown mode current is around 3.5µA. To obtain
0.5µA consumption, the shut command (I2C, pin) has to be received by the SX8722 when the
internal voltage multiplier is not enabled. It means when the supply voltage is above 3V.
Then, if the supply voltage is lowered under 3V, the SX8722 will conserve the 0.5µA
consumption.
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Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
4.3 How to set SX8722 in shutdown mode
4.3.1 I2C Shutdown command
Send the 0x50 command through the I2C interface.
I2C SEQUENCE:
0
0
0
0
0
0
1
0
1
0
0
0
0
0
ACK
1
STOP
0
R/W
1
START
0
Command
0x50
ACK
Slave address
0x48
Figure 6: I2C command to set in shutdown mode
4.3.2 I2C SHUT bit toggle
2
Through the I C interface, send a write mask command at address 00 and toggle the SHUT bit of
the SXCtrl1 register.
I2C SEQUENCE:
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
Figure 7: I2C sequence to set in shutdown mode
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0
0
0
0
0
0
1
0
0
ACK
0
STOP
0
Mask
0x02
ACK
1
ACK
0
ACK
1
R/W
START
0
Data
0x02
Memory address
0x00
Command
0x20
ACK
Slave address
0x48
Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
4.3.3 SHUT pin
Put the SHUT input signal to VSS, the SHUT input is active on negative edge.
4.3.4 Wake-up from shutdown mode to active mode
There are two possible ways to wake-up from the shutdown mode:
•
•
The POR (power-on-reset caused by a power-down followed by power-on).
The RESET pin.
In both case the RAM information is lost. SX8722 configuration must be restored from the EEPROM
saved configuration.
4.3.5 Change from shutdown mode to sleep mode
This is not possible.
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Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
5 Time specifications
In this chapter you will find:
• The start-up time specification of the SX8722.
• The time values to change the mode of SX8722 with the 32k Xtal presence
5.1 Time specification without the 32.768 kHz Xtal
The internal SX8722 RC oscillator accuracy depends on technology tolerance. It can reach ± 50%
difference from one chip to another
In this case, and if no calibration is done, the clock is centred around 1.2 MHz.
SX8722 timing values without Xtal can thus differ of ± 50% to these with a Xtal.
5.2 Start-up time with the 32.768 kHz Xtal presence
The mean time of EEPROM loading at the start-up is 140 ms if configuration data are saved in.
In this case SX8722 will provide the first sample after 180ms.
time before EEPROM
loading: 7.5 [ms]
time after EEPROM
loading: 140 [ms]
time to have the first
sample: 180 [ms]
SX8722
Power-on
t
EEPROM
loading
t
Sample
available
t
Figure 8: start-up timing diagram with EEPROM loading
5.3 Changing mode by pin signal
↓To \ From →
SHUT
SLEEP
ACTIVE
SHUT
inst.
(1)
SLEEP
640 ms
inst.
ACTIVE
650 ms
660 ms
(1)
Table 4: changing mode timings by pin setting
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Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
2
5.4 Changing mode by I C command
↓To \ From →
SHUT
SLEEP
ACTIVE
SHUT
SLEEP
700 µs
inst.
ACTIVE
700 µs
470 µs
(1)
2
Table 5: changing mode timings by I C command
(1) instantaneous
We consider the ACTIVE mode as NOT low power mode. When time to change mode is
instantaneous, it doesn't means that the chip is totally ready to work. There are for examples
initialization times, EEPROM loading or code execution.
We consider the transition time as not low power.
© 2007 Semtech Corp.
www.semtech.com
21
Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
6 ANNEXE
In this chapter you will find:
• The average result of SX8722 current measurements.
Vdd [V]
2.5
5.5
temperature
[°C]
-40
25
85
ISLEEP
[µA]
7.69
8.792
9.536
ISLEEP
[µA]
2.69
2.844
2.976
(1)
ISLEEP [µA]
with XTAL
3.028
3.864
4.362
ISLEEP [µA]
with XTAL(1)
0.988
1.062
1.264
ISHUT
[µA]
2.6
3.478
3.628
ISHUT
[µA]
0.492
0.53
0.69
(1)
IACTIVE
[µA]
176.6
205.8
227.1
(2)
-40
25
85
2.84
3.024
3.196
6.58
7.538
8.146
0.998
1.074
1.292
3.28
4.158
4.426
0.5
0.54
0.73
2.85
3.63
3.538
178.8
212.8
233.8
Table 6: average current measurements
(1) Indirect measurement: at first, the signal command is set on the pin, and then the supply voltage is
changed. The 5.5V orange cases have not real application. The voltage multiplier is forced on.
(2) The measurements are done without activating the PGAs.
© 2007 Semtech Corp.
www.semtech.com
22
Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
7 TAPE & REEL SPECIFICATION
7.1 MLP/QFN (0.70mm - 0.90mm package thickness)
•
•
•
•
•
•
Single Sprocket holes
Tolerances for Ao & Bo are +/- 0.20mm
Tolerances for Ko is +/- 0.10mm
Tolerance for Pocket Pitch is +/- 0.10mm
Tolerance for Tape width is +/-0.30mm
Package Orientation and Feed Direction
Figure 9: Direction of feed
Figure 10: Tape and reel
Pkg size
8x8
carrier tape (mm)
Tape
Width
(W)
16
Pocket
Pitch
(P)
12
Reel
Ao
Bo
Ko
8.30
8.30
1.10
Reel
Size
(in)
13
Reel
Width
(mm)
16.4
Trailer
Length
(mm)
400
Leader
Length
(mm)
400
QTY
per
Reel
3000
Table 7: Tape and reel dimensions
© 2007 Semtech Corp.
www.semtech.com
23
Technical note TN8722.01
SX8722 operating modes
Current consumption and timings
ADVANCED COMMUNICATIONS & SENSING
PRELIMINARY
© Semtech 2007
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Contact Information
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Phone (805) 498-2111 Fax : (805) 498-3804
© 2007 Semtech Corp.
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24