2308
Portable Device Battery/Charger Simulator
The Model 2308 Portable Device Battery/Charger
Simulator is optimized for use in testing mobile
phones and other portable, battery-operated
devices . When a device-under-test (DUT) transi-
tions nearly instantaneously from a sleep or
standby mode to the full power transmit state,
the Model 2308’s rapid response to load changes
means there’s little transient voltage drop from
the programmed output voltage and the output
recovers quickly . This fast response is particu-
larly critical when testing portable devices with
a pulsed mode of operation because it allows
the device to perform properly while it’s being
tested . In contrast, the slow-responding source
voltage typical of conventional power supplies
causes the DUT to perform improperly, lead-
ing to production yield problems and costly
retesting .
Fast transient response power supply
•
specialized dual-channel power
supply for design and testing
of portable, battery-operated
devices
•
ultra-fast response to pulsed
load operation
•
speed-optimized command set
reduces test times
•
Variable output resistance for
simulating an actual battery’s
output response
•
simulate a discharged battery
and test charge control circuit
performance with both a
battery supply that can sink up
to 3a and a charger supply
•
Pulse peak, average, and
baseline current measurements
•
Integrating a/D converter for
more precise measurements
•
100na current measurement
sensitivity
The Model 2308 offers a complete solution for portable device sourcing and load current measure-
ment . It has two independent power supply channels: one is optimized to simulate a battery; the
second channel is optimized to perform like a charger for a rechargeable battery . The battery chan-
nel’s variable output resistance can be used to simulate the internal resistance of a battery so design
and test engineers can simulate a battery’s output for testing devices under realistic operating con-
ditions . This channel also sinks current to simulate a discharged battery . The charger channel can
supply a voltage to test a portable device’s battery charge control circuitry, with the battery channel
acting as the discharged battery load .
In addition to maintaining output voltage levels under difficult load conditions, the Model 2308
can measure a wide dynamic range of load current levels and can measure narrow current pulses
(or pulses as narrow as 50µs) . That makes it ideal for characterizing device power consumption by
making low-level sleep mode measurements as well as pulsed operating load currents .
Maximize production yield with fast response to load changes
Mobile phones, other portable devices (such as Bluetooth headsets, MP3 players, etc .), and RF com-
ponents such as power amplifiers, power transistors, and transmitter modules experience large
instantaneous load changes when they transition from a standby state to full power operation . For a
mobile phone, the load current can change from
aPPlICaTIoNs
a 100mA standby current to a 1A transmission
current or a 10× (1000%) increase in the load
• Design and test of a wide
current . The Model 2308 maintains a reliable,
range of consumer electronics,
stable level of voltage output, even when the
including:
DUT produces large load current changes and/or
has a pulsed operating mode .
– Mobile phones, mobile radios,
The Model 2308’s fast recovery from load
changes helps prevent the causes of false failures
and destroyed devices in production test as well
as field failure quality problems due to compro-
mised components . The Model 2308 assures you
of a stable, constant voltage source to maximize
production yield and minimize production retest
and rework costs .
cordless phones, and bluetooth
headsets
DC POWER SUPPLIES
•
analog output for complete
load current waveform
characterization
•
Catch production wiring
problems immediately with
open sense-lead detection
•
built-in digital voltmeter
•
four built-in digital control lines
– MP3 players, portable digital
assistants (PDas), digital
cameras, GPs receivers, and
notebook computers
• Design and test of electronic
components such as rfIC power
amplifiers, rf power transistors,
and baseband and wireless
chipsets for portable wireless
devices
1.888.KEITHLEY
(U.S. only)
www.keithley.com
A Greater Measure of Confidence
Fast transient response power supply
2308
Portable Device Battery/Charger Simulator
Conventional Power Supply
I
I
Model 2308
ordering Information
2308
Portable Device battery/
Charger simulator
(500mA/
div)
accessories supplied
CD with documentation,
output connectors mating
terminal (part no. Cs-846)
(500mA/
div)
Fast transient response power supply
aCCEssorIEs aVaIlablE
2306-DISP
CS-846
SC-182
Remote Display
Mating Output Connector
Low Inductance Coaxial Cable
Time
100µs/div
Time
100µs/div
IEEE-488 INTErfaCE CoNTrollEr CarDs
KPCI-488LPA IEEE-488 .2 Interface Board for the PCI bus
KUSB-488B IEEE-488 .2 USB-to-GPIB Interface Adapter for USB
Port with built-in 2m (6 .6ft) cable
IEEE-488 INTErfaCE CablEs
7007-05 Double Shielded Premium IEEE-488 Cable, 0 .5m (1 .6ft)
7007-1 Double Shielded Premium IEEE-488 Cable, 1m (3 .2ft)
7007-2 Double Shielded Premium IEEE-488 Cable, 2m (6 .5ft)
7007-3 Double Shielded Premium IEEE-488 Cable, 3m (10ft)
7007-4 Double Shielded Premium IEEE-488 Cable, 4m (13ft)
raCK MouNT KITs
4288-1
Single Fixed Rack Mount Kit
4288-2
Dual Fixed Rack Mount Kit
Compare the response of a conventional power supply (left) with the response of a Model
2308 (right) when both are powering a device operating on the EDGE mobile phone standard.
Note how the conventional power supply distorts the load current and cannot maintain a
stable source voltage, which in turn distorts the rf output signal.
sErVICEs aVaIlablE
2308-3Y-EW
1-Year Factory Warranty Extended to 3 Years for
the Model 2308
2308-3Y-17025 3 (ISO-17025 Accredited) Calibrations within 3
Years of Purchase
2308-3Y-DATA 3 (ANSI-Z540-1 Compliant) Calibrations within 3
Years of Purchase
reduce test costs and increase
throughput with high speed
command structure
To minimize production test times while still
giving you all the information you need to char-
acterize your devices fully, the Model 2308 is
designed with a command structure optimized
for speed, with voltage step times as short as
6ms and DC load current measurements in just
22ms . Commands that combine range changing
and current measurement let you acquire the
command, make the measurement, and transfer
the data in as little as 30ms . In addition, special
operating modes, such as the pulse current step
mode, allow taking a number of measurements
on a complex load current waveform with a
single command .
Characterize load currents for
power consumption verification
Characterizing the battery life of portable
devices demands the ability to measure complex
current waveforms over a wide dynamic range .
The Model 2308 offers a far broader range of
capabilities than conventional power supplies for
measuring low current levels, peak pulse current
levels, long-period load current waveforms, and
multi-level current waveforms . A choice of four
Load Current
Source Leads
DUT
Sense Leads
Power Source
The DC source leads become a transmission line during dynamic load swings.
1.888.KEITHLEY
(U.S. only)
www.keithley.com
A Greater Measure of Confidence
DC POWER SUPPLIES
Model 2308 vs. Conventional
Power supplies
Large load changes will cause a large instan-
taneous drop in a conventional power sup-
ply’s voltage output . If the supply’s recovery
time is long, the DUT will turn off when the
supply voltage falls below the DUT’s low
battery turn-off threshold—producing
a
false failure .
Even if the DUT does not turn
off, the drop-off in input power prevents
the output (RF or a power pulse) from
meeting its specification—a
specification
failure .
Furthermore, the conventional
power supply may have an excessively large
overshoot when the DUT’s load current
transitions from its operating load back to
its standby load . The magnitude of the tran-
sient overshoot voltage could even be large
enough to exceed the maximum safe input
voltage, either rendering the device inoper-
able or damaging some components—a
device failure or a field failure.
Your DC source leads are a transmission line when your
portable device operates in a narrow pulsed mode.
Under pulsed operating conditions, your load circuit is an L-C-R network and that load impe-
dance can cause problems for your power supply . Keithley’s fast transient power supplies are
designed to maintain a stable voltage under difficult, narrow pulse, loading conditions and to
maintain the output voltage, even with long lengths of wire between the power supply and the
DUT . The design of your DC sourcing test circuit requires just as much effort as your AC or RF
test circuits . Using a fast transient response, battery simulating power supply needs to be a key
part of your DC test circuit design .
dI
dt
Fast transient response power supply
(500mV/
div)
V
(500mV/
div)
V
2308
Portable Device Battery/Charger Simulator
I
4
I
3
I
2
I
1
I
5
Load Currents
I
6
Trigger Levels
I
7
ranges (5mA, 50mA, 500mA, and 5A) allows measuring load currents
with exceptional resolution and accuracy .
Measure sleep and standby currents with
the accuracy of integrating a/D technology
The Model 2308 is designed for fast and accurate measurements of devices
in low power modes such as the sleep, hibernate, or standby state . It can
resolve currents down to 100nA and measure them with 0 .2% accuracy .
The Model 2308 uses an integrating A/D converter that continuously
acquires the signal rather than capturing discrete samples; this provides a
more accurate measurement than other A/D techniques . In addition, the
averaging effect built into integrating A/D converters reduces noise and
delivers highly stable current readings . You can measure low and high
currents at the same speed with no degradation in accuracy, so the Model
2308 is equally well-suited for the test line and the design lab .
Measure load currents from pulsed-output devices
Devices like GSM-, EDGE-, WLAN-, and WiMAX-based mobile phones gen-
erate pulsed outputs . Determining their total power consumption requires
measuring both the baseline current and the peak of the pulsed load
current . The Model 2308 can capture peak currents of pulses as short as
50µs and as long as 833ms . Programmable trigger levels allow controlled
capture of the pulse, then the Model 2308’s programmable measurement
delay and acquisition times make it easy to avoid rising edge transients so
the pulse peak can be measured accurately . The instrument can also meas-
ure the pulse baseline current and the pulse average load current .
A long integration current mode supports measuring pulse trains with
periods longer than 850ms . In this mode, the Model 2308 can measure
average current on a load current waveform with a period from 850ms to
60 seconds .
High current level
Trigger level
Fast transient response power supply
With a single command, the Model 2308’s high speed pulse step
current function can quickly capture varying load current levels to
speed test throughput.
a significant time-savings when testing integrated circuits over their allow-
able range of Vcc levels .
Capture the complete load current waveform
Two built-in analog outputs help designers of device’s verify design perfor-
mance and ensure its current draw conforms to design specifications with-
out the need to connect any sensing circuitry in the power supply circuit .
Once these outputs are connected to an oscilloscope or a data acquisition
module, the load current waveform can be displayed or digitized and ana-
lyzed in a computer . When the Model 2308 is connected to a data acquisi-
tion module, the data acquisition module can sample the waveform at any
sampling rate to create a record of any length desired .
Test under realistic conditions with true battery simulation
When a portable battery-operated device transitions from one load current
level to another, the battery voltage supplying the current will drop by
the product of the change in current and the battery’s internal resistance .
During the load current pulse, the device must operate with a voltage
reduced by the battery’s internal resistance . The Model 2308 allows simu-
lating this resistance so its output is almost identical to a battery’s output,
allowing design or production test engineers to test devices or components
under realistic conditions . This patented
1
technique permits the output
resistance to be programmed between 0W and 1W with 10mW resolution .
You can also decrease the voltage and increase the output resistance while
the output is on to simulate the discharge of the battery .
Lithium Ion Battery with
130mΩ Internal Resistance
Model 2308 with Output Resistance
Programmed to 130mΩ
Low current level
High
Time
Low Time
Average Time
(out to 60s with long integration)
The Model 2308 can measure peak pulse currents, average currents,
and baseline currents.
DC POWER SUPPLIES
Take multiple measurements on start-up sequences or
on current levels at different voltage operating levels
Need to analyze a device’s circuitry during the power-up phase as it transi-
tions from a sleep mode or an off-state? The Model 2308’s pulse step cur-
rent function has the speed needed to measure the load current start-up
levels in a single device start-up so that the measurements can be per-
formed in production without an increase in test time .
The pulse step current function also offers a fast way to determine load
currents of different operating states . For example, as source voltage levels
are varied over a device’s operating range, the corresponding operating
current levels can be measured without executing multiple commands for
(1A/
div)
I
(50mV/
div)
V
Time
100µs/div
Time
100µs/div
The Model 2308’s programmable output resistance (right) allows it to
simulate the output of a real battery (left), a capability conventional
power supplies do not have. The 2308 output is identical to the
battery’s response.
1 . U .S . Patent Number 6,204,647 B1
1.888.KEITHLEY
(U.S. only)
www.keithley.com
A Greater Measure of Confidence
Fast transient response power supply
I
8
2308
Portable Device Battery/Charger Simulator
save with multiple instruments in one package –
two power supplies, a DVM, digital controls, and a
remote display
The Model 2308 saves on both instrumentation costs and rack space by
packing two independent power supply channels in one compact, 2U half-
rack enclosure, along with additional capabilities power supplies rarely
offer . For example, the built-in DC digital voltmeter can measure voltages
in the DUT circuitry from -5VDC to +30VDC . The DVM and the battery
channel voltage source can operate simultaneously . For many applications,
the Model 2308 can eliminate the need for a separate DMM .
The digital outputs the Model 2308 provides can sink up to 100mA to con-
trol relays . External relays can be powered either by the internal 5V source
or an external source with a maximum voltage of 24V . For applications that
require only a few digital control lines, the Model 2308 eliminates the need
for an additional control module .
Need to reduce your test
system size or want more sys-
tem organization flexibility?
Then mount the Model 2308
in the back of a test rack or
near the test fixture—mount-
ing the instrument in the
test rack is unnecessary . The
Model 2308’s tiny (4 .6 in . ×
2 .7 in .) remote display can be
The Model 2306-DIsP display can be
mounted anywhere for easy
viewing of the outputs of both
mounted for easy viewing when the
instrument itself must be mounted in
channels . If the Model 2308 is
an inaccessible location.
inaccessible, you can control it
from the remote display because it has all the front panel pushbuttons that
are on the instrument itself .
reduce test system problems with low impedance cable
Keithley’s SC-182 Low Inductance Coaxial Cable is designed to minimize
the impedance and reduce the susceptibility to external EMI in your DC
source-DUT circuit . This cable’s characteristic impedance is nominally 15W
with a low 42nH/ft of inductance and a low 182pF/ft of capacitance . In con-
trast, a typical coaxial cable has 50W or 75W characteristic impedance and
twisted-wire pairs have at least 80W of characteristic impedance .
Test a device’s charge control circuitry
Both channels of the Model 2308 sink up to 3A of current continuously .
Therefore, the battery channel can act like a discharged re-chargeable
battery . The charger channel can supply a charging voltage for use in
testing the operation of the DUT’s charging control circuitry . Because the
charger channel can also act as an electronic load, the battery channel can
operate the device and the charger channel can act as a load to test a bat-
tery capacity monitor or some other device function that requires a load .
Fast transient response power supply
Battery Channel
I
+
–
Battery
Terminals
Charger Channel
I
R
V
battery
+
–
V
charger
> V
battery
Charger
Terminals
for charger control circuit testing, the Model 2308’s battery channel
can sink current to simulate a discharged battery while the charger
channel simulates a charger. one instrument provides high versatility
for portable device testing.
reduce testing errors and retesting costs
with remote sense lead monitoring
Remote sensing capabilities let the Model 2308 ensure the voltage pro-
grammed is what is actually applied to the load . As DUTs are continuously
inserted and removed from test fixtures, the instrument ensures this pro-
grammed voltage is maintained with an open sense lead detection mon-
itor—any break in a sense lead connection is detected immediately . The
open sense lead detection monitor eliminates the possibility that numerous
devices could be tested or calibrated at an incorrect voltage .
+
–
R
sense
+
V
OUT
–
+
V
IN
DVM
–5V to +30V DC
–
The Model 2308’s charger channel contains a built-in DVM, eliminating
the need for a separate instrument in many test systems.
Model 2308 rear panel
1.888.KEITHLEY
(U.S. only)
www.keithley.com
A Greater Measure of Confidence
DC POWER SUPPLIES
Fast transient response power supply
2308
ouTPuT #1 (battery Channel):
DC VolTaGE ouTPuT (1 Year, 23°C ± 5°C)
Portable Device Battery/Charger Simulator
DC CurrENT (1 Year, 23°C ± 5°C) (continued)
SOURCE COMPLIANCE ACCURACy:
±(0 .16% + 5mA) .
2
PROGRAMMED SOURCE COMPLIANCE RESOLUTION:
±1 .25mA .
READBACK ACCURACy: 5A Range:
±(0 .2% + 200µA) .
500mA Range:
±(0 .2% + 100µA) .
50 mA Range:
±(0 .2% + 5µA) .
5mA Range:
±(0 .2% + 2µA) .
READBACK RESOLUTION: 5A Range:
100µA .
500mA Range:
10µA .
50 mA Range:
1µA .
5mA Range:
0 .1µA .
LOAD REGULATION:
0 .01% + 1mA .
LINE REGULATION:
0 .5mA .
STABILITy:
0 .01% + 50µA .
MEASUREMENT TIME CHOICES:
0 .002 to 10 PLC
3
, in 0 .002PLC steps .
AVERAGE READINGS:
1 to 10 .
1 . Peak current can be a max . of 5A provided the average current is within the stated limits and terminals 1 and 6
are used .
2 . Minimum current in constant current mode is 6mA .
3 . PLC = Power Line Cycle . 1PLC = 16 .7ms for 60Hz operation, 20ms for 50Hz operation .
Model 2308 specifications
NoTEs
PulsE CurrENT MEasurEMENT oPEraTIoN
TRIGGER LEVEL: 5A Range:
0A to 5A, in 5mA steps .
500mA Range:
0mA to 500mA, in 0 .5mA or 500µA steps .
50mA Range:
0mA to 50mA, in 0 .05mA or 50µA steps .
5mA Range:
0mA to 5mA, in 0 .005mA or 5µA steps .
TRIGGER DELAy:
0 to 100ms, in 10µs steps .
INTERNAL TRIGGER DELAy:
10µs .
HIGH/LOW/AVERAGE MODE: Measurement Aperture Settings:
33 .3µs to 833ms, in 33 .3µs
steps .
Average Readings:
1 to 100 .
PULSE CURRENT MEASUREMENT ACCURACy
1
(1 year, 23°C ± 5°C):
accuracy ±(% reading + offset)
aperture
<100 µs
100 µs – 200 µs
200 µs – 500 µs
500 µs – <1 PLC
1 PLC
2
>1 PLC
NoTEs
5a range
0 .3% + 2 mA
0 .3% + 2 mA
0 .3% + 2 mA
0 .3% + 900 µA
0 .3% + 900 µA
0 .3% + 900 µA
500ma range
0 .3% + 1 mA
0 .3% + 1 mA
0 .3% + 1 mA
0 .3% + 900 µA
0 .3% + 900 µA
0 .3% + 900 µA
50ma range
0 .3% + 700 µA
0 .3% + 700 µA
0 .3% + 700 µA
0 .3% + 500 µA
0 .3% + 200 µA
0 .3% + 200 µA
5ma range
0 .3% + 200 µA
0 .3% + 100 µA
0 .3% + 100 µA
0 .3% + 90 µA
0 .3% + 90 µA
0 .3% + 90 µA
NoTEs
1 . At PLC (Power Line Cycle) = 1 .
2 . Following 15 minute warm-up, the change in output over 8 hours under ambient temperature, constant load,
and line operating conditions .
3 . PLC = Power Line Cycle . 1PLC = 16 .7ms for 60Hz operation, 20ms for 50Hz operation .
4 . Recovery to within 20mV of previous level .
5 . Remote sense, at terminals 1 and 6, with 4 .5m (15 feet) 16 AWG (1 .31mm
2
) twisted pair, with 1 .5A load change,
(0 .15A to 1 .65A) resistive load only, typical .
DC CurrENT (1 Year, 23°C ± 5°C)
CoNTINuous aVEraGE ouTPuT CurrENT
CHANNEL #2 (CHARGER) OFF:
I = 50W/(V
set
channel 1 + 6V); 5A max .
1
CHANNEL #2 (CHARGER) ON:
I = (50W – power consumed by channel #2)/(V
set
channel 1 + 6V); 5A max .
1
The power consumed by channel #2 is calculated as:
Channel #2 Sourcing Current:
Power consumed = (V
set
channel 2 + 6V) × (current supplied) .
Channel #2 Sinking Current:
Power consumed = 5V × (sink current) .
CoNTINuous aVEraGE sINK CurrENT
CHANNEL #2 (CHARGER) OFF:
0–5V:
3A max .
5–15V:
Derate 0 .2A per volt above 5V . Compliance setting controls sinking .
CHANNEL #2 (CHARGER) ON:
Available Current = (50W – Power consumed by channel #2)/5V; 3A max . (0–5V) .
Derate 0 .2A per volt above 5V .
1 . Based on settled signal: 100µs pulse trigger delay .
2 . Also applies to other apertures that are integer multiples of 1PLC .
bursT MoDE CurrENT MEasurEMENT
MEASUREMENT APERTURE:
33 .3µs to 833ms, in 33 .3µs steps .
CONVERSION RATE:
4100/second, typical .
1
INTERNAL TRIGGER DELAy:
10µs .
NUMBER OF SAMPLES:
1 to 5000 .
TRANSFER SAMPLES ACROSS IEEE BUS IN BINARy MODE
2
:
4400 readings/s, typical (4 bytes
per reading) .
NoTEs
1 . At 33 .3µs aperture .
2 . Display off, Message Exchange Protocol (MEP) off, auto zero off .
DC POWER SUPPLIES
loNG INTEGraTIoN MoDE CurrENT MEasurEMENT
MEASUREMENT TIME, 60Hz (50Hz):
850ms (840ms) to 60 seconds in 1ms steps .
aNaloG ouTPuT
5A/500mA OUTPUT:
1V/A ± 25mA (typical) .
50mA/5mA OUTPUT:
1V/10mA ± 0 .25mA (typical) .
INTERNAL IMPEDANCE:
1000W (nominal) .
1.888.KEITHLEY
(U.S. only)
www.keithley.com
A Greater Measure of Confidence
Model 2308 specifications
OUTPUT VOLTAGE:
0 to +15VDC .
OUTPUT ACCURACy:
(0 .05% + 3mV) .
PROGRAMMING RESOLUTION:
1mV .
READBACK ACCURACy
1
:
±(0 .05% + 3mV) .
READBACK RESOLUTION:
1mV .
OUTPUT VOLTAGE SETTLING TIME:
5ms to within stated accuracy .
LOAD REGULATION:
0 .01% + 2mV .
LINE REGULATION:
0 .5mV .
STABILITy
2
:
0 .01% + 0 .5mV .
MEASUREMENT TIME CHOICES:
0 .002 to 10PLC
3
, in 0 .002PLC steps .
AVERAGE READINGS:
1 to 10 .
TRANSIENT RESPONSE:
High Bandwidth
Low Bandwidth
<35 µs
5
<50 µs
5
Transient Recovery Time
4
5
Transient Voltage Drop
<90 mV
<180 mV
5
REMOTE SENSE:
1V max . drop in each lead . Add 2mV to the voltage load regulation specifica-
tion for each 1V change in the negative output lead due to load current change . Remote sense
required . Integrity of connection continually monitored . If compromised, output will turn off
automatically once settable window (±0 to ±8 volts) around normal voltage exceeded .
VARIABLE OUTPUT IMPEDANCE: Range:
0 to 1 .00W in 0 .01W steps . Value can be changed with
output on .
京公网安备 11010802033920号
EEWORLD
