The SAMES SA9105F Three Phase
bidirectional Power/Energy metering
integrated circuit generates pulse rate
outputs for positive and negative energy
directions, the frequency of which is
proportional to the power consumption.
The SA9105F performs the calculation for
active power.
The method of calculation takes the power
factor into account.
Energy consumption is determined by the
power measurement being integrated over
time.
This innovative universal three phase power/
energy metering integrated circuit is ideally
suited for applications such as residential
and industrial energy metering and control.
The SA9105F integrated circuit is available
in 40 pin dual-in-line plastic (DIP-40), as
well as in 44 pin plastic leaded chip carrier
(PLCC-44) package types.
nExcellent long term stability
nEasily adaptable to different signal
levels
nPrecision voltage reference on-chip
nTwo pulse output formats available
nProtected against ESD
Supply VoltageVDD-V
Current on any PinI
Storage TemperatureT
Operating TemperatureT
Current at any pinI
PIN
STG
O
P
SS
-0.36.0V
-150+150mA
-40+125° C
-40+85°C
-100+100mA
* Stresses above those listed under "Absolute Maximum Ratings" may cause permanent
damage to the device. This is a stress rating only. Functional operation of the device
at these or any other conditions above those indicated in the operation sections of this
specification, is not implied. Exposure to Absolute Maximum Ratings for extended
periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(Over the temperature range -10°C to +70°C#, unless otherwise specified.)
ParameterSymbolMin TypMax Unit Condition
Operating Temp. Range #T
O
Supply VoltageVDD-V
Supply CurrentI
DD
-25+85°C
4.55.5V
SS
10mA
Nonlinearity of
Power Calculation-0.3+0.3% 1% - 100% of
rated power
Current Sensor Inputs (Differential)
Input Current RangeI
II
-25+25µAPeak value
Voltage Sensor Inputs (Asymmetric)
Input Current RangeI
IV
-25+25µAPeak value
Pins FOUT1,FOUT2,DIR
Output Low VoltageV
Output High VoltageV
Pulse Rate: FOUT1, FOUT2 f
OL
OH
p
VDD-1VIOH = -2mA
064HzSpecified linearity
VSS+1VIOL = 5mA
0180HzMin and max limits
OscillatorRecommended crystal:
TV colour burst crystal, f = 3.5795 MHz
Pin VREFWith R = 24 kΩ
Ref. Current-I
Ref. VoltageV
#
Extended Operating Temperature Range available on request.
R
R
sames
455055µAconnected to V
1.11.3VReferred to V
SS
SS
3/12
Page 4
SA9105F
PIN DESCRIPTION
PinPin
PLCCDIP
635GNDGround
4228V
2916V
534IVP1Analog input for Voltage : Phase 1
433IVP2Analog input for Voltage : Phase 2
332IVP3Analog input for Voltage : Phase 3
186IIN1Inputs for current sensor : Phase 1
197IIP1
208IIN2Inputs for current sensor : Phase 2
219IIP2
2210IIN3Inputs for current sensor : Phase 3
2311IIP3
3219OSC1Connections for crystal or ceramic resonator
3320OSC2(OSC1 = Input ; OSC2 = Output)
3521FOUT1Pulse rate outputs
3723FOUT2
3925DIRDirection indication output
938CON1Connections for outer loop capacitors of A/D
1039COP1converters
837CON2
736COP2
130CON3
231COP3
2613CONP
2512COPP
131CIN1Connections for inner loop capacitors of A/D
1140CIP1converters
153CIN2
142CIP2
175CIN3
164CIP3
2815CINP
2714CIPP
4329VREFConnection for current setting resistor
4127TP27Test pin. Connect to V
3017TP17Manufacturer's test pins (Leave unconnected)
3118TP18
3622TP22
3824TP24
4026TP26
Designation Description
DD
SS
Positive Supply Voltage
Negative Suply Voltage
SS
4/12
sames
Page 5
SA9105F
sames
Page 6
SA9105F
2.Analog Input Configuration
The current and voltage sensor inputs are illustrated below.
These inputs are protected against electrostatic discharge through clamping
diodes, in conjunction with the amplifiers input configuration.
The feedback loops from the outputs of the amplifiers AI and AV generate virtual
shorts on the signal inputs. Exact duplications of the input currents are generated
for the analog processing circuitry
V
DD
IIP
V
CURRENT
SENSOR
INPUTS
IIN
SS
V
DD
V
SS
V
DD
A
I
IVP
VOLTAGE
SENSOR
INPUT
DR-00949
V
SS
GND
A
V
3.Electrostatic Discharge (ESD) Protection
The SA9105F integrated circuit's inputs/outputs are protected against ESD.
4.Power Consumption
The overall power consumption rating of the SA9105F integrated circuit is less than
50mW with a 5V supply.
6/12
sames
Page 7
5.Pulse Output Signals
The calculated power is divided down to a pulse rate of 64Hz, for rated conditions
on both FOUT1 and FOUT2.
The format of the pulse output signal, which provides power/energy and direction
information, is the only difference between the signals on FOUT1 and FOUT2.
The direction of the energy flow is defined by the mark/space ratio on FOUT1, while
the pulse width defines the direction on FOUT2.
SA9105F
Positive Energy Flow
Negative Energy Flow
Wave form on FOUT1
Wave form on FOUT2
t
pp
mm
t
pp = 1.1ms
t
pp
mm
t
pn
mm
t
pn = 3.4ms
t
pn
mm
Wave form on DIR
DR-00950
An integrated anticreep function ensures no metering at zero line currents.
The formula for calculating the Output Frequency (f) is given below:
f = 11.16
3.58MHz 3 * I
FOUTX
*
FOSC * (II1 IV1) + (II2 IV2) + (II3 IV3)
*
2
R
Where FOUTX= Nominal rated frequency (64Hz)
FOSC= Oscillator frequency (2MHz ...... 4MHz)
II1, II2, II3= Input currents for current sensor inputs (16µA at rated line current)
IV1, IV2, IV3= Input currents for voltage sensor inputs (14µA at rated line voltage)
I
R
= Reference current (typically 50µA)
TYPICAL APPLICATION
In the Application Circuit (Figure 1), the components required for a three phase power
metering application are shown. Terminated current transformers are used for current
sensing.
The most important external components for the SA9105F integrated circuit are:
sames
7/12
Page 8
SA9105F
C7, C9, C10 and C11 are the outer loop capacitors for the integrated oversampling
A/D converters. The typical value of C7 is 2.2nF and the value of C9, C10 and C11 is
560pF.
The actual values determine the signal to noise and stability performance. The tolerances
should be within ± 10%.
C4, C5, C6 and C8 are the inner loop capacitors for the integrated oversampling A/D
converters. The typical value of C4, C5, C6 and C8 is 3.3nF. Values smaller than 0.5nF
and larger than 5nF should be avoided.
Terminated current sensors (current transformers) are connected to the current sensor
inputs of the SA9105F through current setting resistors (R8 ..R13).
The resistor values should be selected for an input current of 16µA
into the SA9105F,
RMS
at the rated line current.
The values of these resistors should be calculated as follows:
Phase 1:
R8 = R9 = (IL1/16µA
) * R18/2
RMS
Phase 2:
R10 = R11 = (IL2/16µA
) * R19/2
RMS
Phase 3:
R12 = R13 = (IL3/16µA
Where I
R18, R19 and R
LX
20
) * R20/2
RMS
=Secondary CT current at rated conditions.
=Current transformer termination resistors for the three phases.
R1 + R1A, R4 and R15 set the current for the phase 1 voltage sense input. R2 + R2A, R5 +
P5 and R16 set the current for phase 2 and R3 + R3A, R6 + P6 and R17 set the current for phase
3. The values should be selected so that the input currents into the voltage sense inputs
(virtual ground) are set to 14µA
for nominal line voltage. Capacitors C1, C2 and C3
RMS
are for decoupling and phase compensation.
R
+ P14 defines all on-chip bias and reference currents. With R14+ P14 = 24kΩ, optimum
14
conditions are set. R14 may be varied within ± 10% for calibration purposes. Any changes
to R
will affect the output quadratically (i.e: ∆R = +5%, ∆f = +10%).
14
XTAL is a colour burst TV crystal (f = 3.5795 MHz) for the oscillator. The oscillator
frequency is divided down to 1.7897 MHz on-chip, to supply the digital circuitry and the
A/D converters.
8/12
sames
Page 9
SA9105F
Figure 1: Application Circuit for Three Phase Power/Energy Measurement.
Note 1: Resistor (R8, R9, R10, R11, R12 and R13) values are dependant upon the selected
values of the current transformer termination resistors R18, R19 and R20.
Note 2: Capacitor values may be selected for DC blocking and to compensate for phase
errors caused by the current transformers.
Note 3: Capacitor (C12) to be positioned as close to Supply Pins (VDD & VSS) of IC-1, as
possible.
ORDERING INFORMATION
Part NumberPackage
SA9105FPADIP-40
SA9105FFAPLCC-44
sames
11/12
Page 12
SA9105F
Disclaimer:The information contained in this document is confidential and proprietary to South African Micro-
Electronic Systems (Pty) Ltd ("SAMES") and may not be copied or disclosed to a third party, in whole or in part,
without the express written consent of SAMES. The information contained herein is current as of the date of
publication; however, delivery of this document shall not under any circumstances create any implication that the
information contained herein is correct as of any time subsequent to such date. SAMES does not undertake to inform
any recipient of this document of any changes in the information contained herein, and SAMES expressly reserves
the right to make changes in such information, without notification,even if such changes would render information
contained herein inaccurate or incomplete. SAMES makes no representation or warranty that any circuit designed
by reference to the information contained herein, will function without errors and as intended by the designer.
Any sales or technical questions may be posted to our e-mail address below:
energy@sames.co.za
For the latest updates on datasheets, please visit our web site:
http://www.sames.co.za
South African Micro-Electronic Systems (Pty) Ltd
P O Box 15888,33 Eland Street,
Lynn East,Koedoespoort Industrial Area,
0039Pretoria,
Republic of South Africa,Republic of South Africa