Theory of Operation—2246 1Y and 2246 Mod A Service
DIO:
Data 10 pin. This pin is tied to the
Measurement Processor MB DATA line. Data
to be clocked into the control register is pre
sented here, and status data can be read
out on this pin when the RD input is low
(tri-state output). See Table 3-7.
TDI: Trigger data input pin. When A3=A2=1,
data on this pin is sent to the DIO pin (when
RD is low ).
RD: Read enable input (active low). Bringing
this pin low causes internal status data
(selected with A3-A0) to be presented on
the DIO pin for transfer to the Measurement
Processor.
WR: Write enable input (active low). A
negative-going pulse on this pin performs
actions described in the Table 3-7.
SOUT: Strobe output pin (active low ). When
A3, A2, A1_;_and AO = 1111, SOUT goes low
when the WR pin is pulled low. Otherwise,
SOUT is always high.
A3, A2, A1, AO:
Address inputs. The
ADDR0-ADDR3 selection bits are latched
from the Measurement Processor address
bus by U2512, Diagram 8.
A GATE:
A Sweep Gate input (active low).
B GATE:
B Sweep Gate input (active low).
TC:
Timing clock input.
LFC:
Low-frequency clock input. A signal
derived from the calibrator circuit is used for
skewing the chop-clock phase.
ROR:
Readout request input (active low). A
low causes the CH 1 EN, CH 2 EN, CH 3 EN,
CH 4 EN, HD1, HDO, and TS outputs to all go
low, and allows the ROB input to have com -
plete control of the BLANK output. If ROB is
low when ROR goes low, then the internal
timing will be such that the BLANK output will
go high quickly enough to blank the display
before switching transients can be shown on
screen (see the detailed description of the
readout interface).
ROB
: Readout blank input (active low ). Dur-
ing readout active time (ROR=low), the ROB
input is inverted and sent to the BLANK
output.
OSC OUT:
The external holdoff oscillator
output drives this pin. A falling edge causes
the internal holdoff counter to increment.
OSC RST:
Oscillator reset output. Internal
logic causes this output to go high to dis
charge the external holdoff oscillator timing
capacitor at the end of holdoff (see detailed
description of the holdoff tim er operation).
CH 1 EN:
Channel
1
enable output (active
high).
CH 2 EN:
Channel 2 enable output (active
high).
CH 3 EN:
Channel 3 enable output (active
high).
CH 4 EN:
Channel 4 enable output (active
high).
3-17
Содержание 2246 1Y
Страница 13: ...2246A Service 7062 01 X The 2246 1Y or 2246 Mod A Portable Oscilloscope ...
Страница 35: ......
Страница 69: ...Theory of Operation 2246 1Y and 2246 Mod A Service 15 V 6081 07 3 32 Figure 3 4 Simplified Sweep Circuit ...
Страница 91: ...Theory of Operation 2246 1Y and 2246 Mod A Service 6081 12 6557 99 3 54 Figure 3 9 Power Supply block diagram ...
Страница 139: ......
Страница 185: ......
Страница 187: ......
Страница 278: ...Figure 9 5b Detailed 2246 1Y or 2246 Mod A block diagram part 2 R E ...
Страница 287: ......
Страница 304: ...A D D J U N 1991 ...
Страница 311: ...2246 1Y and 2246 Mod A Service WAVEFORMS FOR DIAGRAM 1 0 V r l III B f e I l i 6555 39 ...
Страница 314: ...15 14 13 12 11 10 9 8 7 6 5 12 11 10 9 8 7 AT117 A TI 271 1 2 3 4 5 6 6555 70 Figure 9 8 Hybrid pin identifiers ...
Страница 319: ......
Страница 320: ......
Страница 321: ...2246 1Y and 2246 Mod A Service WAVEFORMS FOR DIAGRAM 2 SET READOUT CONTROL CCW OFF 6555 40 ...
Страница 323: ......
Страница 324: ......
Страница 326: ...A B C P E F G ...
Страница 327: ......
Страница 331: ......
Страница 337: ......
Страница 340: ......
Страница 343: ...C l rti ...
Страница 344: ...WAVEFORMS FOR DIAGRAM 5 2246 1Y and 2246 Mod A Service HORIZ MODE A A SEC DIV 2M S HOLDOFF MIN CCW ...
Страница 345: ...HORIZ MODE ALT A SEC DIV 2M s B SEC DIV 5 mS HOLDOFF MIN DELAY INTENSIFIED ZONE STARTS MIDSCREEN ...
Страница 347: ...BEV JUNE 1991 7062 18 ...
Страница 349: ...2246 1Y and 2246 Mod A Service WAVEFORMS FOR DIAGRAM 6 6555 43 I ...
Страница 354: ...A L B i C 1 D 1 E i F i G 1 2 3 4 5 6 7 8 2246 1Y AND 2246 MOD A _________A fc A A REV JUNE 1991 7062 19 ...
Страница 355: ...I BOARD LOCATION 8K 8J 8H 7H 8H 8H 7J 8D 7H 8H 8J 8J 7K 8K 10D 6L 6K 6L 6K 6G 5H I ...
Страница 362: ......
Страница 372: ...2246 1Y and 2246 Mod A Service WAVEFORMS FOR DIAGRAM 9 MORE ...
Страница 373: ... 6555 72 6557 88 ...
Страница 375: ......
Страница 376: ...SCHEM LOCATION BOARD LOCATION 2E 2B 7F 4B 4J 5D 3J 5C 4L 6D 3L 6C 5L 7D 3L 7D 3M 7D 5M 7D IB 1A 1C 1A 2B 1A 3B 1A ...
Страница 380: ...WAVEFORMS FOR DIAGRAM 10 ...
Страница 387: ...WAVEFORMS FOR DIAGRAM 11 6555 73 6557 48 ...
Страница 394: ...WAVEFORMS FOR DIAGRAM 12 2246 1Y and 2246 Mod A Service i f I S 1 f c i 4 i ...
Страница 395: ...WAVEFORMS FOR DIAGRAM 12 cont 2246 1Y and 2246 Mod A Service ...
Страница 397: ......
Страница 398: ......
Страница 400: ...REV JUNE 1991 7062 39 ...
Страница 401: ......
Страница 403: ......
Страница 404: ......
Страница 406: ...B 2246 IV AND 2246 MOD A ...
Страница 407: ......
Страница 408: ......
Страница 414: ... _ 5 ...
Страница 415: ...2246 1Y 2246 MOD A ...
Страница 416: ......
Страница 423: ...2246 1Y 2246 MOD A ...
Страница 424: ...2246 1Y 2246 MOD A ...
Страница 425: ......
Страница 433: ......