sx8724s Semtech Corporation, sx8724s Datasheet - Page 13

• Manufacturer Part Number: sx8724s
• Description: Zoomingadc For Sensing Data Acquisition
• Manufacturer: Semtech Corporation

Revision 1.0
© Semtech
6 General Description
The SX8724S is a complete low-power acquisition path with programmable gain, acquisition speed and resolution.
6.1 Bloc diagram
6.2 VREF
The internally generated V
voltage reference for the ZoomingADC.
This reference voltage is directly connected to one of the ZoomingADC reference multiplexer inputs.
The bandgap voltage stability is only guaranteed for V
bandgap voltage could reduce by up to 50mV.
The bandgap has relatively weak output drive so it is recommended that if the bandgap is required as a signal input
then PGA1 must be enabled with gain = 1.
6.3 GPIO
The GPIO block is a multipurpose 2 bit input/output port. In addition to digital behavior, D0 and D1 pins can be
programmed as analog pins in order to be used as output (reference voltage monitoring) and input for an external
ADVANCED COMMUNICATIONS & SENSING
D0/REF
D1/REF
AC2
AC3
AC4
AC5
AC6
AC7
OUT
IN
February 2011
SX8724S
REF
V
REF
is a trimmed bandgap reference with a nominal value of 1.22V that provides a stable
+
-
AC1
+
+
AC0
-
-
GPIO
Figure 4. SX8724S bloc diagram
PGA
CHARGE
PUMP
Page 13
CONTROL LOGIC
BATT
voltages of 3V and above. As V
ZoomingADC
4MHz
OSC
ZoomingADC for sensing data acquisition
ADC
SPI
TM
BATT
drops down to 2.4V, the
MISO/READY
SX8724S
READY
VPUMP
VBATT
SCLK
MOSI
VSS
SS
www.semtech.com
DATASHEET