Welch Allyn Atlas - Page 3

A
A
B
B
C
C
D
D
E
E
4 4
3 3
2 2
1 1
+6V Buck
(5.68V nominal)
On/Off Switch
Page 1
Rick Myers
Rick Myers
Mar 5, 1999
Mar 5, 1999
620002.dsn
5-39118
JAC 3/15/99 LPP
L.Phillips
Z. Psenicnik
J. Bello
3/16/99
3/16/99
3/17/99
B See ECN worksheet
C
Improvements for ESD
and Fast Transients
4/27/995-39456 LPP LPP
5-39822 LPP LPP6/23/99
Mods to U2 clock line,
NVRAM pullup
D 5-39934 LPP 7/9/99
REV
Description
ECN/ECO Init
Date Ckd
A Release to Production
620002
D
Power Supply - DC/DC
C
36Friday, July 09, 1999
Title
Size
Document Number
Rev
Date: Sheet of
Welch Allyn Inc.
Schematic:
Release For Production
Approved
Checked
Designed
Drawn
Initial Date
U301-out Q303-b
U301-fb
Q303-c
C311-1
Q304-e
U301-osc
U301-5
U301-comp
Q305-g
u304-fb
up-reset
PIC-audio
Q305-s
d304-1
d304-2
Q301-G
C328-1
On-Off
Q302-B
ACON
5Vref
+5V
+6V
+3.3V
filt+12V
+12V
Vb
VBackup
BackupBattery
PIC-Clk
Speaker-Audio
HRESET
U2-Reset
PIC-Vprog
Rec-Data
Rec-Clock
On/Off-Key
PIC-Data
AC+12V
D
D
D
D D
D
D
D
D
D
D
D
TP312
U302
LM2940CT-5.0
1 3
2
IN OUT
GND
R313
10
U303
LF33CV
1 3
2
IN OUT
GND
C305
.01uF
R309
10K
+ C316
10uF
D304
MMBD354LT1
1
3
2
+ C323
4.7uF
D301
BAV99L
1
3
2
Q306
2N7002
3
1
2
C320
.047uF
+ C324
4.7uF
TP308
+ C306
330uF
+ C314
330uF
Q304
MMBT3904L
3
1
2
R310
1.96K
TP301
TP315
C307
.047uF
+ C319
100uF
R319 19.6K
TP304
R302
100K
C322
.047uF
+ C302
1uF
R316
100
R301
51.1K
R314
100
Q302
MMBT3904L
3
1
2
TP306
TP313
TP302
+ C304
330uF
L302
47uH
Q303
MMBT3904L
3
1
2
C303
.01uF
Q305
MTP23P06V
2
1
3
4
TP309
TP317
C311
2200pF
U301
UC3843A
3
57
14
1
10
8 12 9 11
VFB
ISENSERT/CT
VREF
COMP
OUT
PWR-GND Vcc GND Vc
TP316
R305
100K
U304
LP2951CD-3.3
8
7
3
6
2
1
5
4
VIN
FDBK
SHTDN
TAP
SENS
VOUT
ERR
GND
TP305
R318
10K
R307
7.5K
R320 1.62K
R312
1.96K
D303
MBRS340
R304
127K
TP26
C321
.047uF
U305
D620361-MX10000
2
5
7
4
3
6
1 14
8
9
10
11
12
13
ClkIn/Osc1/RB5
TC5/TOCK1
RC3
Vpp/MCLR/RB3
Clkout/Osc2/RB4
RC4
Vdd
Vss
RC2
RC1
RC0
RB2
RB1
RB0
R311
10K
R303
10K
C325
.047uF
TP303
TP320
+ C315
1uF
R306
10K
Q301
MTP23P06V
2
1
3
4
C313
.047uF
TP321
TP27
TP310
C317
.047uF
C310
2200pF
TP318
L301
47uH
R308
27.4K
+
C301
1000uF
C326
.047uF
TP319
TP307
D305
NO LOAD
1
3
2
C327
.047uF
+ C328
1uF
C309
.047uF