Ericsson R250s PRO Troubleshooting Instructions page 5

1.3 Abbreviations
B:
C:
D:
F:
H:
J:
L:
N:
R:
S:
V:
X:
Z:
DCIO:
GND:
LED:
LO:
RTC:
SIMCONCLK:
SIMCONDAT:
SIMCONRST:
SIMVCC:
VBATT:
VDIG:
VDSP:
VLCD:
VRAD:
VVCO:
I2C:
PWM:
4/00021-2/FEA 209 544/18 D
Crystal.
Capacitor.
Digital circuit.
Over voltage protection.
Buzzer, LED, pads for display.
Connector.
Coil.
Analogue circuit, power amplifier at some phones.
Resistor.
Keyboard pads.
Transistor, diode.
Contact surface at the circuit board.
Filter.
DC voltage through the system connector for charging.
Ground.
Light emitting diode e.g. the background illumination.
Local oscillator.
Real Time Clock, the clock that keeps track of time.
Signal from the processor used for communication to SIM, clock signal.
Signal from the processor used for communication to SIM, data signal.
Signal from the processor used for communication to SIM, reset signal.
Feed voltage for SIM.
Battery voltage.
DC voltage for the processor and memory.
DC voltage for the DSP (Digital Signal Processor).
DC voltage for the display that controls the contrast.
DC voltage for the radio part except the synthesizer.
DC voltage for the synthesizer.
Two line serial communications standard using one clock and one data
line.
Pulse Width Modulation
Standard Trouble Shooting Instructions
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