pkd01 Analog Devices, Inc., pkd01 Datasheet - Page 12

• Manufacturer Part Number: pkd01
• Description: Monolithic Peak Detector With Reset-and-hold Mode
• Manufacturer: Analog Devices, Inc.

PKD01
APPLICATIONS INFORMATION
Optional Offset Voltage Adjustment
Offset voltage is the primary zero scale error component since a
variable voltage clamp limits voltage excursions at D
and reduces charge injection. The PKD01 circuit gain and opera-
tional mode (positive or negative peak detection) determine the
applicable null circuit. Figures 5 through 8 are suggested circuits.
Each circuit also corrects amplifier C offset voltage error.
25k
V
V
NOTES:
1. NULL RANGE =
2. DISCONNECT R
3. REPEAT NULL CIRCUIT FOR RESET BUFFER AMPLIFIER B IF REQUIRED.
V
V
NOTES:
1. NULL RANGE =
2. DISCONNECT R
3. REPEAT NULL CIRCUIT FOR RESET BUFFER AMPLIFIER B IF REQUIRED.
IN
V
V
IN
S
IN
S
S
0.1 F
+
+
–
+
–
+
R
A
, R
100k
B
20k
R1
R1
0.1 F
AND R
R5
2M
1k
R1
R2
V
C
S
–
20
C
R3
R4
NOT NECESSARY FOR AMPLIFIER B ADJUSTMENT.
C
V
FROM C
V
FROM C
S
S
( )(
( )
R5
R4
R1
R2
DET
RST
H
A
B
H
R1 + R3
AFTER AMPLIFIER A ADJUSTMENT.
AFTER AMPLIFIER A ADJUSTMENT.
DET
RST
R1
A
B
D
)
1
D
1k
R2 = R3 + R4
R1
1
1000pF
C
H
1000pF
C
PKD01
H
C
PKD01
C
2M
R
C
1
2M
’s anode
–15V
R
C
200k
R
R
1k
V
–15V
A
B
OUT
200k
R
R
1k
V
A
B
OUT
A. Nulling Gated Output g
be conducting to close the feedback circuit during amplifier A
V
slightly. With DET = 0 and V
output. Adjust the null potentiometer until V
adjustment, disconnect R
B. Nulling Gated g
input to V
1, RST = 1 and adjust the null potentiometer for V
The circuit gain—inverting or noninverting—will determine which
null circuit illustrated in Figures 5 through 8 is applicable.
25k
25k
OS
V
V
IN
IN
V
V
V
V
NOTES:
1. NULL RANGE =
2. DISCONNECT R
3. REPEAT NULL CIRCUIT FOR RESET BUFFER AMPLIFIER B IF REQUIRED.
NOTES:
1. NULL RANGE =
2. DISCONNECT R
3. REPEAT NULL CIRCUIT FOR RESET BUFFER AMPLIFIER B IF REQUIRED.
adjustment. Resistor network R
S
S
S
S
+
–
–
+
R4 = R2 R1
IN
0.1 F
20k
R1
R5
= 0 V and monitor the PKD01 output. Set DET =
20k
0.1 F
R1 + R2
R3
R4
R3
20
C
C
R1
V
FROM C
V
FROM C
20
R4
S
S
m
( )
( )
R4
R3
R3
R5
Amplifier B. Set Amplifier B signal
H
H
C
AFTER AMPLIFIER A ADJUSTMENT.
AFTER AMPLIFIER A ADJUSTMENT.
from C
DET
RST
DET
RST
B
B
A
A
m
IN
Amplifier A. Diode D
= 0 V, monitor the PKD01
D
D
H
1
1
.
A
– R
R2
R2
C
1000pF
1000pF
C
H
H
C
cause D
PKD01
PKD01
C
C
OUT
= 0 V. After
GAIN = 1 +
1
OUT
to conduct
2M
2M
R
R
C
1
C
= 0 V.
must
–15V
–15V
R1 + R3
R
200k
1k
200k
R
R
R
1k
V
R2
V
A
B
A
B
OUT
OUT