Canon 580EX - Speedlite II - Hot-shoe clip-on Flash, Руководство по обслуживанию

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Technical Information
. CIRCUIT DESCRIPTION
. Power Source
(1) When the batteries are installed, BATT1 is input to IC16 through L4 and D40.
(2) When the D40 voltage output enters IC16, VCC is output from pin 1 and input to IC107S
(MPU) pin 94.
(3) VCC is also input to IC4 (voltage-detection IC). If the voltage is 3.2V or higher, "H" is
output to IC107S pin 90. With "H", IC107S becomes operational.
Due to C55, VCC steadily increases until it reaches 4.8V.
(4) When IC107S becomes operational and the Power SW is on, "L" is input to pin 116, pin
115 goes "H", and IC15, IC17, and RQ100S turn on.
(5) When IC17 turns on, VCC is supplied to IC108S (op amp), IC106S (comparator IC),
IC102S (metering IC), IC101S (EEPROM), and other pull-up components.
(6) IC107S pin 114 goes "H". 2.5V of which the reference voltage of 3.2V from pin 30 of
IC102S is applied across R326 and R325 passes through R108S, and the voltage goes
into pin 1 of IC106S. From IC15 pin 1, 5.5V is output, passes through RQ25, divided into
R156 and R157, and goes into pin 3 of IC106S. IC106S inputs are compared. If pin 1
of IC15 is at least 5V, IC107S pin 114 goes "H", the output from pin 4 of IC106S passes
through TH2 and IC304 and controls FET6 and FET7 to start recharging.
(7) Since the converter holds pin 1 of IC15 above 5V, pin 1 of IC16 is kept at 4.8V.
(8) The standard voltage of IC102S pin 30 (3.2V) is supplied to pin 38, and 43 of IC107S.
* Power SW does not perform operations (4) - (8) during power OFF and SE.
<Operation Sequence>
(1) → (2) → Power switch on → (4) → (5) (6) (7) (8)
. Recharging
(Recharging Start)
(1) 2.5V output of which 3.2V reference voltage supplied by IC102S pin 30 is applied over
R326 and R325 passes through R108S to pin 1 of IC106S. The voltage of IC15 pin 1
(normally 5.5V) passes through RQ25 to voltage divider R156 and R157. The result
is supplied to pin 1 of IC106S (usually 2.75V). If IC106S pin 3 is higher than pin 1, an
"L" output from pin 4 turns on RQ101S. When RQ101S turns on, the "H" output from
IC107S of pin 114 as a power supply, FET6 and FET7 turn on alternately via TH2 and
IC304.
(2) FET6 and FET7 turn on by turns and T1 oscillates, then passes through D302, D303
and D304 to reach C14 (main capacitor) and passes through R28 to recharge C21 and
C22 (trigger capacitors). If the main capacitor's voltage reaches 165V, IC107S pin 120
outputs "H" to RQ5, and Q36 turns on to make D305 and D306 conductive, and then
transformer connection is switched from parallel to in series.
(3) C14's recharging voltage is applied across R16/R17, and R18. The voltage goes into
IC107S pin 47 (A/D Detection). Recharging continues until the input voltage reaches
about 2.4V.
(An input voltage of 2.4V is equivalent to a charge of 330V on the main capacitor)
(Input voltage of 0.0125V is equivalent to 1.71V on the main capacitor.)