Sony Ericsson C903 Cyber-shot, Troubleshooting Manual

Page: 35 / 129

C903
1228-1147 rev. 1
TROUBLESHOOTING Backup Capacitor Test
T
R
O
UBL
ESHOOT
ING
- Charging Test
Backup Capacitor Test
To perform this test use:
- Phone with the ETS SW
- Power Supply Channel 1 VBATT: Instrument settings: Voltage: 3.8V, Limiter: 2A
- Power Supply Channel 2 DCIO/SEPI: Instrument settings Voltage: 5V, Limiter: 2A
This test should be performed in 3 steps:
Step1:
Measure the voltage at the Backup Capacitor by using Fault Trace SW- Logic -
ADC Values – Read ADC Value (Reading 1).
Step2:
This step should be made 30 seconds after Step 1. Measure the voltage at the
Backup capacitor by using Fault Trace SW - Logic – ADC Values - ADC Channels
– Read ADC Value (Reading 2).
Step3:
Compare the difference between Reading 1 and Reading 2 with the reference table
below. If the Reading 1 value is between 50 and 680 go to Interval 1, if it is between
681 and 800 go to Interval 2, if it is between 801 and 880 go to Interval 3 and
compare with the Reading 2 – Reading 1 Min and Max Limits.
Reference Table:
Min Max Unit
Absolute readout
Reading 1
50 880 Dec
Reading 1 (Dec) Reading 2 – Reading 1 (Dec)
Min Max
Interval 1 (50 – 680) 20 210
Interval 2 (681 – 800) 5 30
Interval 3 (801 – 880) 0 10
Note! The upper table contains the absolute limits for the readouts. The lower table
contains the allowed delta between the first and the second readout, separated in
time with 30 seconds.
Note! If the readings are out of limits then SL 5 replace C2214 (Backup Capacitor)
if the problem persists then SL 5 Replace N2000 SL 4 Escalate.
Charging Test
To perform this test use:
-
Phone with the Signalling SW (SSW)
-
Dummy Battery connected to Power Supply Channel 1 (VBATT)
Note! The Dummy Battery should have approximately 120K Ohm resistance between GND and
BDATA.
-
Power Supply Channel 1 (VBATT)
Instrument settings:
Voltage: from 3.0 Volt to 4.2 Volt, according to VBATT row in the Reference Table.
Limiter: 2A
-
Power Supply Channel 2 (DCIO/SEPI)
Instrument settings:
Voltage: 5V
Limiter: 2A
Test instructions:
-
Disconnect the DCIO/SEPI Cable between each measurement and wait for phone to shutdown before
changing VBATT voltage.
-
Take a note of current measurements at Power Supply Channel 2 DCIO/SEPI and display charging
indicator X seconds after DCIO/SEPI cable has been inserted according to the Test Time row in the
reference table below.
-
Compare the test results with the reference table below, tol/-20%.
Reference Table
VBATT x
Volt 3.0v 3.1v 3.2v 3.3v 3.4v 3.5v 3.6v 3.7v 3.8v 3.9v 4.0v 4.1v 4.2v
Test Time
x sec.
15s 15s 15s 25s 25s 25s 35s 35s 35s 35s 35s 25s 45s
DCIO/SEPI
Current
mA
250mA 250mA 250mA 500mA 600mA 700mA 900mA 900mA 900mA 900mA 900mA 900mA 0mA
Display
indicates
charging
Nothing Nothing Nothing Yes Yes Yes Yes Yes Yes Yes Yes Yes
Fully
Charged
Note! The Power Supply Channel 1 (VBATT) must allow reverse current.
If the charging current is NOT equal to the reference table then go to: Charging Problems TRS Guide
If the charging current is equal to the reference table then insert the normal battery and test the charging
current to verify if the phone battery is working properly.
Measure the voltage at the battery to define the current level.
If the battery is receiving the right current, then the phone and the battery are working properly.
SEMC Troubleshooting Manual
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