+ FEATURES
+ Bi-directional active and reactive power/energy
measurement
+ RMS Voltage and frequency measurement
+ SPI communication bus
+ Meets the IEC 521/1036 Specification requirements for
Class 1 AC Watt hour meters
samessames
Single Phase Power / Energy IC
with SPI Interface
SA9903B
1/12
SPEC-0051 (REV. 2)
26-02-01
+ Meets the IEC 1268 Specification requirements for VAR
hour meters
+ Protected against ESD
+ Total power consumption rating below 25mW
+ Adaptable to different current sensor technologies
+ Operates over a wide temperature range
+ Precision voltage reference on-chip
DESCRIPTION
The SAMES SA9903B is a single phase bi-directional
energy/power metering integrated circuit that performs
measurement of active and reactive power, mains voltage and
mains frequency.
The SA9903B is pin compatible to the SA9603B. New features
include, RMS mains voltage and accurate reactive power
measurements.
Measured values for active and reactive energy, the mains
voltage and frequency are accessible through a SPI bus from
24 bit registers.
This innovative universal single phase power/energy metering
integrated circuit is ideally suited for energy calculations in
applications such as electricity dispensing systems (ED's),
residential municipal metering and factory energy metering
and control.
TheSA9903B integrated circuit is available in both 20 pin dual-
in-line plastic (DIP-20), as well as 20 pin small outline (SOIC-
20) package types.
Figure 1: Block diagram
IVP
SPI
VOLTAGE
REF.
DI
VSS
VDD
DO
FMO
VREF
Dr-01583
OSC2OSC1
GND
ACTIVE
REACTIVE
RMS
VOLTAGE
MAINS.
FREQ.
CURRENT
ADC
VOLTAGE
ADC
SCK
CS
OSC
IIP
IIN
TEST