(No.RA033<Rev.001>)1-65
5.3
If normal power is not obtained, please follow the steps below
(1) Is the set current when the output becomes the upper limit appropriate for the output?
When an excessive electric current is observed for the too little output, there is the example that the input to a module is not
enough. So,Is drive power enough?
Try to readjust it if incompatible.And confirm a course reaching the module.
(2) The output is the state of the upper limit, and observe gate voltage at that time.
If around 5V that is the hardware-like upper limit appears, there is the abnormality on an output step or the output course.
For example, it is power supply, module, coupling capacitor, LPF.
When the power supply voltage at the module terminal abnormally descends, you should confirm each joint, main fuse, current
detection resistance (R4).
(3) When you cannot confirm enough gate voltage, there is the problem with a control block or a detection block.
Can "PWR_LIM" observe an appropriate value (limit adjustment up to around 3V)?
The protector circuit malfunctions (in normal time Q2, Q451 OFF)?
The reflection side detection circuit misdetects it (the R61 side of the coupler including non-connection)?
Is the antenna switch replaced definitely?
IC703 OUTY(R725) output
3.3V.
No
IC703 INA and INB input 3.3V.
No
Check IC703's input of R714
and R715.
Yes
Failure of R912 or IC703 are
doubted.
No
Yes
PWRONRSTn High : OK
No
X901 oscillate 24MHz(R903 or
R904)
Check around X901
Yes
Main Clock 24MHz : OK
Checking the System Boot Mode.
R915, R936, R999 are 3.3V,
and R916, R921 are 0V.
No
Check around the resistors.
No
Yes
NAND Boot selected.
IC830 VCC(L833) input 3.3V
No
Failure of L833 or IC830 (or
C831-834) are doubted.
No
Yes
NAND Flash VCC3.3V : OK
IC830 WAIT0 (R837) become
Low
(busy state) sometime in power
up sequence.
No
Check around IC830 of IC16 or
IC901 R833,R834,R836-R842,
R845-R852, and IC830 are
doubted.
No
Yes
IC900 can read NAND Flash
IC904 input 2A(5) and outpu
2Y(3) are same .
No
Check around IC904
Yes
IC901 can transmit TxD to
IC200
IC905 input 2A(5) and output
2Y(3) are same .
No
Check around IC905
Yes
IC901 can receive RxD from
IC200.
IC750 15DDR output 1.5V
(L767).
No
R800 removed and the 15DDR
becomes normal.
No
Failure of IC750 is doubted.
Yes
Failure of the following parts
are doubted.
C796-C806,C808-C812
No
VREF is 0.75V (R801 and
R802) .
No
Failure of the following parts
are doubted.
R801,R802,
(C793-C795,C802,C807)
No
Yes
DDR VREF : OK
/DDR_RESET(R935) is 3.3V.
(Do not held low.)
No
Failure of the following parts
are doubted. R799, R935
No
Yes
DDR RESET : OK
DDR_CKE(R952) is 3.3V.
(Do not held low.)
No
Failure of the following parts
are doubted. R951,R952
No
Yes
DDR CKE : OK
DDR_CK(R953) and /DDR3_CK
(R954) output 400MHz.
No
Failure of the following parts
are doubted. R953,R954,
No
Yes
DDR CLK : OK
IC 901 output DDR CS0, RAS,
CAS, WE normally.
No
Failure of the following parts
are doubted. R947-R950.
No
Yes
DDR control signals : OK
IC901 output DDR Address
normally.
No
Failure of the following parts
are doubted. R956-R969.
No
Yes
DDR control signals : OK
IC901 Reset and
Main clock is fine.
Communicate
between IC901 and
IC200 seems to be fine.
DDR3 seems to be fine.
NAND
boot
seems
to
be
fine.
Failureof MPU(IC901) is doubted.
Failure of DDR3(IC791) is doubted.
From A
