ETC GP520A

Programmable Analog
Signal Processor
GENNUM
C␣ ␣ O␣ ␣ R␣ ␣ P␣ ␣ O␣ ␣ R␣ ␣ A␣ ␣ T␣ ␣ I␣ ␣ O␣ ␣ N
GP520A - DATA SHEET
FEATURES
Principle features of the preamp are the input impedance
100 kΩ and a gain of 14 dB.
• programmable parameters
- gain
- low pass filter
- high pass filter
- AGC threshold
- release time
- MPO
- receiver bias voltage
The programmable filter block is composed of a low pass
and high pass filter which generates a range of high and
low pass corner frequencies. Although the control current
to this block varies linearly, linear to logarithmic conversion
is performed internally in order to adjust the corner frequencies
logarithmically. Both filters feature a 12 dB/octave rolloff
and unity gain.
• on-chip voltage regulator
• typical gain 60 dB
• voltage drive output stage
• telecoil preamp
The filters are followed by an AGC block. Up to 35␣ dB of
adjustable gain is provided as well as programmable
threshold and release time. The attack time of the AGC
block remains fixed and is independent of the release
time. The output current is driven into the preamp of the
clipper, thus, the AGC converts a voltage input into a
current output and is therefore, a transconductance block.
STANDARD PACKAGING
• Chip (136 x 110 mils)
Au Bump
CIRCUIT DESCRIPTION
The next stage is an electronic MPO control peak “clipper”
providing electronic clipping of the signal and setting of
the maximum output level. The clipper output is also a
transconductance block and drives a 40 kΩ resistor (ROUT␣ 8)
tied to the supply.
The GP520A is a programmable analog signal path IC
designed for use in hearing instruments. The GP520A’s
programmable parameters are adjusted by external
programming currents, such as generated by the GP521.
The GP520A provides a 2.5 µA reference current for use by
the GP521. Sixteen settings are possible in the GP521,
allowing the Programmable Current Sink (PCS) to sink
between 0 and 1.875 x IREF .
The input of the final stage is an inverting operational
amplifier. A feedback resistance of 240 kΩ is provided
internally and this final stage is thus configured as a
voltage drive output stage. The DC bias current through
the receiver is also programmable.
The GP520A is composed of five functional blocks. The
input preamp, a filter block, the AGC block, MPO clipper
and the output stage.
V REG
V CC
A OUT
9
15
HPFB
HP
18
BUFFER
IN
24
LPFB
22
19
BUFFER
OUT
26
RECT.
IN
CAGC
27
1
DELTA
CCOMP OUT B
IN
3
5
31
B OUT CCLIP
7
30
V cc
13
VOLTAGE
REGULATOR
FULL WAVE
RECTIFIER
R
THRESHOLD
R OUT 8
+
28
LP
FILTER
AGC
VC AMP
CLIPPER
-
50k
COUT
8
R
29
+ HP
+
2R
PREAMP
A IN 14
AVERAGING
CIRCUIT
RIN14
-
FILTER
-
40K
R
11
DOUT
OUTPUT
+
LIN/LOG
CONVERTER
12
DIN
-
10K
P GND
10
RF
6
GND
20
I HP
LIN/LOG
CONVERTER
21
I LP
LIN/LOG
CONVERTER
I REF
16
I REF
25
I REL
VBIAS
2
23
I THRESH
I GAIN
4
I CLIP
17
I BIAS
All resistors in ohms, all capacitors in farads unless otherwise stated.
FUNCTIONAL BLOCK DIAGRAM
Revision Date: May 1998
Document No. 510 - 78 - 06
GENNUM CORPORATION P.O. Box 489, Stn. A, Burlington, Ontario, Canada L7R 3Y3 tel. +1 (905) 632-2996
Web Site: www.gennum.com E-mail: [email protected]
CHIP PAD DIAGRAM
ABSOLUTE MAXIMUM RATINGS
30
31
CCOMP
28
29
CCLIP
27
TEL-B TEL-C RECT.IN
PARAMETER
VALUE / UNITS
1
CAGC
Supply Voltage
5V
2
I THRESH
3
DELTA OUT
4
I CLIP
I GAIN 23
5
B IN
LPFB 22
6
GND
I LP 21
7
B OUT
I HP 20
8
COUT
9
V CC
Pad 3, 8, 10, 11, 13, 17
-0.1 V to VCC + 0.1 V
Pad 1, 15, 16, 18, 19, 22, 24, 26
-0.1 V to VREG + 0.1 V
Pad 4, 5, 7, 14, 20, 21, 23, 25, 27
-0.1 V to 0.7 V
Pad 2
VREG -0.7 V to VREG + 0.1 V
CAUTION
CLASS 1 ESD SENSITIVITY
BUFFER OUT 26
I REL 25
BUFFER IN 24
GP520A
I BIAS 17
10 DIN
I REF 16
11 DOUT
12
ELECTRICAL CHARACTERISTICS
HP 19
HPFB 18
A OUT 15
PGND
13 V REG
A IN 14
All parameters are measured at TA = 25oC
All gains are calculated from equation G = 20 LOG (∆OUT/∆IN) where ∆OUT and ∆IN are appropriate voltage or current increases.
All resistances are calculated according to equation R = (V P - VQ) / ICOND where V P is voltage on the pad loaded with I COND current.
V Q - quiescent (unbias) voltage measured on the pad, (nothing connected to the pin).
V P is the actual voltage measured on the pad at given condition (where P is pad number).
For all graphs IREF is measured with 0.5V biased voltage on pin 16.
GENERAL
PARAMETER
SYMBOL
Amplifier Current
IAMP
Minimum Voltage
VCC
CONDITIONS
MIN
All PCS set to 15
TYP
-
1.1
MAX
600
-
-
UNITS
µA
-
V
REGULATOR TESTS
Regulator Voltage (Pad 13)
VREG
Short Circuit Current (Pad 13)
ISC
S1 — closed
-
0.98
-
V
-
2.0
-
mA
-
2.5
-
µA
CURRENT REFERENCE
Current Reference (Pad 16)
IR
PREAMPLIFIER
Quiescent Voltage on Pad 14
VQ14
600
-
-
mV
Quiescent Voltage on Pad 15
VQ15
600
-
-
mV
Input Resistance (Pad 14)
RIN 14
I14 = 0.3µA (S2 closed)(Note 1 )
-
100
-
kΩ
Output Swing High (Pad 15)
VOH
V 14 = 0.8V (S3 closed)(Note 1)
200
-
-
mV
Output Swing Low (Pad 15)
VOL
V1
-200
-
-
mV
Max Source Current (Pad 15)
ISOURCE
V14 = 0.8V (S3, S4 closed)
V15 = VQ15+100mV
30
-
-
µA
Max Sinking Current (Pad 15)
ISINK
V14 = 0.4V (S3,S4 closed)
V15 = VQ15-100mV
30
-
-
µA
Preamp Voltage Gain
GAIN
V14= V Q14 ± 10mV (S3 closed)
-
14
-
dB
NOTE: 1. VOL = VOH = V P15 – VQ15
510 - 78 - 06
=
0.4V (S3 closed)
All switches remain OPEN unless otherwise stated in CONDITIONS column.
2
S4
-
-
+
+
1.3V
9
S1
10n 10n
68n
10K
V15
A OUT
V CC
V REG
68n
27 1
26
31
B OUT
B OUT
CAGC
15
30 5
VCC
7
VOLTAGE
REGULATOR
13
2k2
3µ3
11
A IN
14
DOUT
+
PREAMP
S2
S3
-
RIN14
40K
10K
I14
V14
+
12
P GND
6
GND
All resistors in ohms, all capacitors in
farads unless otherwise stated.
Fig. 1 Preamplifier and Regulator Test Circuit
HIGH PASS FILTER
PARAMETER
SYMBOL
CONDITIONS
MIN
Quiescent Voltage on Pad 18
VQ18
-
Quiescent Voltage on Pad 19
VQ19
Quiescent Voltage on Pad 20
VQ20
Maximum DC Current from Pad 19
IHP MAX
Minimum DC Current from Pad 19
Buffer Gain
MAX
UNITS
650
-
mV
-
650
-
mV
-
550
-
mV
I HP = 0µA ( S3 closed)
-
2
-
µA
IHP MIN
IHP=1.875 x I R (S3 closed)
-
200
-
nA
GAIN
V19 = VQ19 ± 100mV
-
0
-
dB
-
13
-
kΩ
(S2 closed)
Input Resistance Pad 20
RIN20
IHP = I R
TYP
All switches remain OPEN unless otherwise stated in CONDITIONS column.
+ V19
V CC
V
REG
18
10n 10n
68n
10K
CAGC
LPFB
HPFB HP
9
68n
S3
S2
19
22
27 1
26
30
B
B OUT
IN
31 5
13
2k2
R
+ HP
3µ3
VCC
7
11
2R FILTER
-
DOUT
R
LIN/LOG
CONVERTER
12
P GND
RIN
0.6 V
20
I HP
6
GND
LIN/LOG
CONVERTER
21
I LP
All resistors in ohms, all capacitors in
farads unless otherwise stated.
I HP
Fig. 2 High Pass Filter DC Test Circuit
3
510 - 78 - 06
LOW PASS FILTER
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Quiescent Voltage on Pad 21
VQ21
-
550
-
mV
Quiescent Voltage on Pad 22
VQ22
-
650
-
mV
Quiescent Voltage on Pad 24
VQ24
-
650
-
mV
Quiescent Voltage on Pad 26
VQ26
-
650
-
mV
Maximum DC Current from Pad 22
ILP MAX
ILP = 0µA (S1 closed)
-
2.0
-
µA
Minimum DC Current from Pad 22
ILP MIN
ILP =1.875 x I R (S1 closed)
-
0.7
-
µA
Output Swing High (Pad 26)
VOH
V24 = VQ24 + 100mV (S2 closed)(Note 1)
-
100
-
mV
Output Swing Low (Pad 26)
VOL
V24 = VQ24 - 100mV (S2 closed )(Note 1)
-
-100
-
mV
Max Sinking Current from Pad 26
ISINK
V24 = 0.4V;
30
-
-
µA
-30
-
-
µA
V 26 = VQ26 - 100mV
(S2, S3 closed)
Max Sourcing Current to Pad 26
V24 = 0.8V; V 26 = VQ26 ± 100mV
ISOURCE
(S2, S3 closed)
Buffer Gain
GAIN
V26 = VQ26 ± 100mV
-
0
-
dB
Input Resistance (Pad 21)
RIN21
ILP = I R
-
13
-
kΩ
NOTE: 1. VOH = V OL = V P26 - V Q26
All switches remain OPEN unless otherwise stated in CONDITIONS column.
+
+
V24
V26
+1.3 V
S2
S1
V CC
LPFB
9
V REG
68n
S3
BUFFER
IN
22
BUFFER
OUT
24
68n 10n
RECT. C
AGC
IN
27
1
30
26
10n 10K
B
31
IN
5
B
OUT
VCC
7
13
2k2
R
+ LP
3µ3
11
FILTER
-
DOUT
R
LIN/LOG
CONVERTER
0.6 V
I REF
R IN
12
P GND
6
GND
21
I LP
16
I REF
All resistors in ohms, all capacitors in
farads, unless otherwise stated.
I LP
Fig. 3 Low Pass Filter DC Test Circuit
510 - 78 - 06
4
1n5
TP
680p
2n2
V CC
A OUT
9
13
15
2n2
68n
HPFB
18
BUFFER
LPFB
OUT
24 BUFFER
26 27
22
IN
HP
19
VOLTAGE
REGULATOR
68n
10n 10n
10K
BOUT
1
31
30 5 BIN
7
VCC
2k2
R
+
3µ3
LP
FILTER
11
DOUT
R
AIN 14
+
2R
PREAMP
10µ
RIN14
+ HP
FILTER
-
40K
R
10K
LIN/LOG
CONVERTER
0.6V
LIN/LOG
CONVERTER
0.6 V
20
I HP
12
6
P GND GND
21
I LP
All resistors in ohms, all capacitors in
farads, unless otherwise stated.
PINK
NOISE
GENERATOR
I LP
I HP
Fig. 4 AC Test Circuit for High & Low Pass Filters
10k
IHP = 1.875 x IR
CORNER FREQUENCY (HZ)
CORNER FREQUENCY (Hz)
10k
1k
1k
100
80
0
0.25
0.5
0.75
1
1.25
1.5
1.75
700
2
NORMALIZED I HP / I R CURRENT
0
0.25
0.5
0.75
1
1.25
1.5
1.75
2
NORMALIZED I HP / I R CURRENT
Fig. 6 Low Pass Filter Corner Frequency vs I LP Current
(Note 1) (Fig.4 Test Circuit)
Fig. 5 High Pass Filter Corner Frequency vs IHP Current
(Note 1) (Fig.4 Test Circuit)
NOTES: 1. Corner frequency calculated in reference to signal at 3 kHz
5
510 - 78 - 06
AGC CONTROL STAGE
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX UNITS
Quiescent Voltage on Pad 2
VQ2
ITHRESH = I R
-
400
-
mV
Quiescent Voltage on Pad 3
VQ3
IGAIN = IR x 1.875
-
700
-
mV
Quiescent Voltage on Pad 23
VQ23
-
500
-
mV
Quiescent Voltage on Pad 25
VQ25
-
500
-
mV
Quiescent Voltage on Pad 27
VQ27
-
600
-
mV
Release Current Max (Pad 1)
IREL MAX
IREL = 0 (S1 closed)
-
300
-
nA
Release Current Min (Pad 1)
IREL MIN
IREL = 1.875 x I R (S1 closed)
-
30
-
nA
Input Resistance (Pad 25)
RIN25
IREL = I R
-
17
-
kΩ
Input Resistance (Pad 27)
RIN27
I27 = ± IR
-
4
-
kΩ
Max Transconductance (Pad 26 to VO ) G MAX
IGAIN =I R x 2 x 1.875 VP26=30 mV pp
ITHRESH =1.875 x I R (Note 1)
-
160
-
µA/V
Gain Range (Pad 26 to V )
o
GAIN RANGE
ITHRESH =1.875 x I R (Note 2)
V26 = 25 mV pp
-
33
-
dB
Output Limiting Level (Pad 3)
OUTLIM
ITHRESH =I R, I GAIN = 2 x 1.875 x I R
-
0.7
-
µARMS
-
13
-
dB
-
5
-
V26 = 100 mV pp (Note 3)
Limiting Level Range
LIMRANGE
IGAIN = I R x 2 x1.875 (Note 4)
V26 = 100 mV pp
AGC Compression Ratio
CMPRAT
ITHRESH =I R
IGAIN = 2 x 1.875 x I R (Note 5)
Unless otherwise stated in CONDITIONS column all switches remain OPEN, all current sources are 0µA
NOTES:
1. G MAX = V o / (V 26 x 1M)
4. LIM
RANGE
5. CMP
2. GAINRANGE = 20 LOG ( V o[I GAIN = 2 x1.875 x I R]/ V o [I GAIN = 0])
RAT
=
= 20 LOG (Vo [I THRESH=1.875 x I R]/Vo [I THRESH =0] )
10
20 LOG (V o [ V 26=5.62mV RMS]/V o[V 26=17.8mV RMS ])
-45dBV
-35dBV
3. OUT LIM = V / 1M
o
R1=1M
+12V
2 7
6
LT001
3
+
4
0.1
68n
V IN
LPFB
9
V
REG
13
68n
10µ
1.3 V
22
VOLTAGE
REGULATOR
BUFFER
OUT
BUFFER
IN
24
26
RECT.
IN
27
FULL WAVE
RECTIFIER
R
10n
S1
10k
DELTA
OUT
C
AGC
1
3
31
AVERAGING
CIRCUIT
B IN
7
-12V
VCC
30
RF
THRESHOLD
2k2
+
3µ3
5
10n
B OUT
VO
LP
FILTER
AGC
-
11
DOUT
R
AIN 14
V REG - 0.6 V
LIN/LOG
CONVERTER
12
P GND
6
23
2
I THRESH IGAIN
25
I REL
GND
I REL
I THRESH
IGAIN
Fig. 7 AGC Control Stage Test Circuit
510 - 78 - 06
6
All resistors in ohms, all capacitors in
farads unless otherwise stated.
IINNIN = 63 dBV
1
30
ITHRESH = 1.875 x IR
IN = - 63 dBV
20
R1=100kΩ
GAIN (dB)
RELEASE TIME (s)
IGAIN = 3.75 x IR
0.1
10
0
-10
0.01
0
0.25
0.5
0.75
1
1.25
1.5
1.75
2
0
0.5
NORMALIZED I REL / I R CURRENT
Fig. 8 Release Time vs I REL (Fig.7 Test Circuit)
1.5
2
2.5
3
3.5
4
GAIN / I R CURRENT
Fig. 9 AGC Gain vs IGAIN (Fig.7 Test Circuit)
-40
1
RF = 50kΩ
IGAIN = 3.75 x I R
VIN = - 30 dBV
-50
CLIP LEVEL (Vp-p)
INPUT THRESHOLD (dBV)
1
NORMALIZED I
-60
(S3-b)
0.1
-70
0
0.25
0.5
0.75
1
1.25
NORMALIZED I THRESH / I
1.5
1.75
0.01
2
R CURRENT
0
0.25
0.5
0.75
1
1.25
1.5
1.75
2
NORMALIZED I CLIP / I R CURRENT
Fig. 10 Threshold Level vs I THRESH (Fig.7 Test Circuit)
Fig. 11 Output Swing vs ICLIP (Fig.13 Test Circuit) (note 1)
0.3
BIAS VOLTAGE (V)
I10 = 0µA
0.25
0.2
0.15
0.1
0
0.25
0.5
0.75
1
1.25
1.5
1.75
2
NORMALIZED I BIAS / I R CURRENT
Fig. 12 Receiver Bias Voltage vs IBIAS (Fig. 14 Test Circuit)
NOTE: 1.
Switch S2 - open, S4 - closed.
7
510 - 78 - 06
CLIPPER STAGE
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Quiescent Voltage on Pad 5
V Q5
(S1 closed)
-
550
-
mV
Input Bias Current (Pad 5)
I BIAS
RF1 =1M RF2=0Ω ( Note 1 )
-
0
-
nA
Quiescent Voltage on Pad 4
V Q4
-
500
-
mV
Quiescent Voltage on Pad 8
V Q8
-
1.2
-
V
Output Swing High 1 (Pad 8)
V OH1
5
-
-
mV
-5
-
-
mV
( Note 3)
-
1
-
Output Swing Low 1 (Pad 8)
V OL 1
I IN = +1µA
I CLIP = 0µA
(Note 2 )
I IN = -1µA
I CLIP = 0µA
(Note 2 )
Output Clip Symmetry 1
V SYM 1
Output Swing High 2 (Pad 8)
V OH 2
I IN = 5µA
I CLIP = 1.875 x I R ( Note 2)
-
50
-
mV
Output Swing Low 2 (Pad 8)
V OL 2
I IN = -5µA
I CLIP = 1.875 x I R ( Note 2)
-
-50
-
mV
Output Clip Symmetry 2
V SYM 2
( Note 3)
-
1
-
Output Resistance (Pad 8)
R OUT 8
I P8 = 10µA (S2 closed )
-
40
-
kΩ
Clipper Voltage Gain
GAIN
VIN = 50mV pp (S3-b )
I CLIP=1.875 x IR (Note 4)
-
12
-
dB
All switches remain as shown in the Test Circuit unless otherwise stated in CONDITIONS column.
NOTES: 1. IBIAS
= (V7
– V7
) / 1MΩ
RF = 1MΩ
2. V OL
3. VSYM = (2VOH / ( VOH - VOL ))
RF= 0Ω
4. GAIN = 20 log (V8 / V7)
= V OH = V Q8 - V8
10 K
10µ
b
S3
VIN
S2
S1
a
IIN
9
26
I
RF=10k
68n 68n
1.3 V
P8
10n
10n
27 1 31
7
5
VCC
8
30
VCC
13
2k2
ROUT
3.3
VC AMP
12
CLIPPER
11
4
6
All resistors in ohms, all capacitors
in farads unless otherwise stated
ICLIP
Fig. 13 Clipper Test Circuit
510 - 78 - 06
8
OUTPUT STAGE
PARAMETER
SYMBOL
Quiescent Voltage on Pad 17
V17
Min Receiver Bias Voltage
VREC MIN
Max Receiver Bias Voltage
MIN
TYP
MAX
UNITS
-
1.2
-
V
I BIAS = 0µA (Note 1)
-
100
-
mV
VREC MAX
I BIAS = IR x 1.875 (Note 1)
-
300
-
mV
Input Resistance Pad 17
RIN17
I BIAS = IR
-
40
-
kΩ
Internal Feedback Resistor
RF
I 10 = I R
-
240
-
kΩ
Max Sinking Current (Pad 11)
I SINK
(S1 closed)
-
10
-
mA
NOTE:
1. V REC= V cc - V11
CONDITIONS
All switches remain as shown in the Test Circuit otherwise stated in the CONDITION column.
68n
10n
68n
9
I 10
10k
+1.3 V
26
27
1
B
IN
5
D
IN
B OUT
7
V CC
10n
30
10
31
RF
V
REG 13
S1
-
3µ3
OUTPUT
+
2k2
11
D
OUT
V BIAS
R IN 17
12
P GND
6
17
I BIAS
GND
All resistors in ohms, all capacitors in
farads, unless otherwise stated.
Fig. 14 Output Stage Test Circuit
COMMENTS:
1. Pin 23 and Pin 4 represent virtual ground inputs.
2. If the length of the wires between the current sources and the GP520A is
extensive, it may be necessary to connect an RC filter close to the
appropriate GP520A pin for noise immunity.
e.g.
100k
4
ICLIP
10µ
GP520A
All resistors in ohms, all capacitors in
farads, unless otherwise stated.
9
510 - 78 - 06
V CC
C4
C6
C5
C7
C8
C12
2n2
2n2
1n5
680p
68n
68n
10n
9
R
27
1
FULL WAVE
RECTIFIER
AVERAGING
CIRCUIT
26
C11
10n
31
3
7
5
30
THRESHOLD
R OUT 8
+ LP
8
AGC
FILTER
-
50k
VC AMP
CLIPPER
C10
R
14
22n
24
50k
VC
68n
V cc
29
MIC
22
VOLTAGE
REGULATOR
28
C2
18 19
15
13
C1 +
3µ3
C9
C3
RIN14
+
PREAMP
-
+ HP
FILTER
-
2R
RF
40k
OUTPUT
+
R
10k
LIN/LOG
CONVERTER
12
6n8
10
6
21
20
LIN/LOG
CONVERTER
I REF
LIN/LOG
CONVERTER
2
25
16
11
VBIAS
4
23
17
V cc
All resistors in ohms, all capacitors in farads unless otherwise stated.
Fig. 15 Typical Application Circuit
V CC
10k
C6
1n5
15
18 19
22
C5
C7
C8
C12
C9
680p
68n
68n
10n
68n
24
R
FULL WAVE
RECTIFIER
AVERAGING
CIRCUIT
31
3
10n
7
5
30
THRESHOLD
8
VC AMP
AGC
FILTER
CLIPPER
C10
R
2n2
14
T
1
-
29
3u3
27
+ LP
50k
1u
26
C11
50k
VC
V cc
VOLTAGE
REGULATOR
28
RIN14
MIC
2n2
C4
2n2
9
13
1k
C1
C3
2n2
+
PREAMP
-
2R
+ HP
FILTER
-
10
R
40k
OUTPUT
+
M
R
2n2
10k
LIN/LOG
CONVERTER
12
6
20
LIN/LOG
CONVERTER
I REF
LIN/LOG
CONVERTER
21
16
25
2
11
VBIAS
23
4
17
All resistors in ohms, all capacitors in farads unless otherwise stated.
Fig. 16 Typical Telecoil Application Circuit
DOCUMENT IDENTIFICATION: DATA SHEET
The product is in production. Gennum reserves the right to make
changes at any time to improve reliability, function or design, in
order to provide the best product possible.
REVISION NOTES:
Updated to Data sheet
Gennum Corporation assumes no responsibility for the use of any circuits described herein and makes no representations that they are free from patent infringement.
© Copyright September 1989 Gennum Corporation.
All rights reserved.
510 - 78 - 06
6n8
F
10
Printed in Canada.
V cc