SX8722I070LF SEMTECH [Semtech Corporation], SX8722I070LF Datasheet - Page 103

• Manufacturer Part Number: SX8722I070LF
• Description: High gain acquisition for sensor interface
• Manufacturer: SEMTECH [Semtech Corporation]

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.
15.4. Shutdown mode
15.4.1. Description
This is a very low-power mode because all circuit clocks and all peripherals are stopped. Only some service blocks remain
active.
15.4.2. Operating specifications in shutdown mode
Summary
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.
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.
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.
15.4.3. How to set SX8722 in shutdown mode
I2C Shutdown command
Send the 0x50 command through the I2C interface.
I2C SHUT bit toggle
Through the I2C interface, send a write mask command at address 00 and toggle the SHUT bit of the SXCtrl1 register.
ACS - Revision 4.2
©2008 Semtech Corp.
ADVANCED COMMUNICATIONS & SENSING
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
No possible I2C communication
October 2008
Page 103
High gain acquisition for sensor interface
DATASHEET
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SX8722