Evaluation Board for the SA9904B Energy
Metering IC
PM9904BPD
FEATURES
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Designed to
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be used together with accompanying
software as fully functional three phase trivector meter.
Better than class 1 operation.
On board power supply.
Two on-board LED’s for active and reactive pulse output.
3 Phase 4 wire configuration.
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sames
On-board LCD display.
On-board current transformers.
Isolated connection to PC parallel port.
Easy accessible test pins.
Micro-controller plug-in support
DESCRIPTION
This application note describes the PM9904BPD evaluation
board and together with the SA9904B data sheet provides a
complete evaluation platform. The SA9904B is an accurate bi-
directional power / energy measurement IC with serial (SPI)
interface measuring active as well as reactive power / energy,
RMS voltage and frequency. More detailed information
specific to the of SA9904B can be found in its datasheet.
The PM9904BPD module is designed for a three-phase four-
wire applications, referenced to neutral. The mains voltages
easily connect to module by way of a Molex connector (SK1).
The 3 on-board current transformers measures the current in
each phase. A simple capacitive power supply supplies the
energy metering IC with power. The LM431 regulators are
used to generate a 5 V supply voltage for the on-board opto-
couplers. Provision has been made to connect an external 5V
power supply to drive the isolated opto-coupler.
The SA9904B forms the energy/power metering front-end of
the module and connects to the SPI bus. Sharing the SPI bus
is the SA8807A LCD driver which is capable of driving 96
segments on a 4 back plane LCD.
The PM9904BPD evaluation board is configured and
calibrated via the parallel port of a PC. The data interface
between the evaluation board and the PC is fully isolated.
The PM9904BPD module can easily be connected to a micro-
controller. The SAMES micro-controller board connects to the
evaluation module by means of JP1 thereby creating a
complete power meter without the PC interface. Physically the
micro-controller board plugs into the evaluation module with its
opto-coupler facing the mains connector (SK1). It shares the
SPI bus with the SA8807A onboard LCD controller.
SK1
VDD
GND
Power
Supply
GND
VSS
LCD
DISPLAY
PCVSS
PCVDD
JP4
SK3
VDD
PCVDD
PCVSS
CT1
Resistor
Network
JP1
SA8807A
JP2
CT2
Resistor
Network
SA9904A
J12
F50
JP3
CT3
PCVSS
Resistor
Network
Test Pins
VDD
VSS
PCVSS
Test Pins
Figure 1: Block diagram
SPEC-0448 (REV. 6)
1/22
19-06-02
SAMES [ SAMES ]
