Aaron's Synth DIY Datasheet and Ap Note Collection
Some Useful Parts-Related Links
Assorted Notes
BJT
- 2N3904 - general purpose NPN
- 2N3906 - general purpose PNP
- Analog
Devices MAT02 dual NPN
matched (MAT02EH $15.05/1 Digikey)
- Analog
Devices MAT03 dual PNP
matched ($6.96/1000 Analog Devices, $9.45/20 Digikey - but not in stock as of
3/25/06)
- Analog
Devices MAT04 quad NPN
matched (MAT04FP $6.78/1 Digikey)
- Analog
Devices SSM2210 dual NPN
matched ($2.24/1000 Analog Devices, $4.79/1 Digikey)
- Analog
Devices SSM2220
dual PNP matched ($2.73/1000 Analog Devices, $3.91/2500 Digikey)
- THAT series:
300 matched quad NPN, 320 matched quad PNP, 340 matched dual NPN/dual PNP
- National LM194/LM394
matched dual NPN (LM394, $3.30/1K Linear Systems, $5.80/1 Digikey)
(LM194 is improved version of LM394; I've usually only
seen LM394 in synth schematics)
- Linear Systems LS358
log conformance dual PNP
- Linear Systems LS318
log conformance dual NPN
- Linear Systems
LS351/351/352 dual PNP
- 2SC1583 NPN pair (5 pin, tied
emitters) - out of
production ($1.25/each from
Adafruit
Industries)
- 2SC3381 NPN pair (6 pin, separate
emitters) - out of
production, similar characteristics to the 2SC1583 (these were
advertised for $1.25/each from
Electronix Online, but I tried
to order some, and they said they'd been backordered for a year!!!)
- 2SA798 PNP pair (5 pin, tied
emitters) - out of production,
($0.45/each at
Electronic Surplus Inc.)
- 2SA1349 PNP pair (6 pin,
separate emitters) - out of production (Anyone have
a source for these? I haven't been able to find them...)
- NTE42 (2SC1583 replacement) ($1.84/each at Mouser)
- NTE43 (2SA798 replacement) ($1.98/each at Mouser)
-
Intersil HFA 3xxx
Arrays HFA3046 (five NPN; $3.75/1 Digikey), HFA3127 (five NPN: $4.28/1
Digikey), HFA3128 (five PNP; $4.28/1),
HFA3096 (3 NPN, 2 PNP; $3.18/1) (not available in through-hole)
- CA3046
five NPN, Q1 and Q2 have emitters tied, substrate is tied to one of the
other emitters - used in many classic Electronotes
VCO designs, and the Serge PTO ($0.45/each/25 Jameco)
- CA3083
five independent NPN with a separate substrate pin; Q1 and Q2
are "matched at low current" (a favorite of Ian Fritz; he says
they have "low Re and
very good matching (way better than spec.)... still my favorite for NPN
expo converters (use transistor #3 for HF
tracking)") ($0.89/each)
- CA3096 3 NPN, 2 PNP on a common
substrate with a separate connection - used as an
OTA by Sergio Franco in a SVF design
JFET
MOSFET
- 2N7000 N-channel enhancement-mode
MOSFET
(suggested by Tim Daugard) - general purpose
- Supertex VN0104 N-channel
enhancement-mode MOSFET
(recommended by Ian Fritz for
sawtooth core discharging)
- 4007UB
- "dual complementary pair and an
inverter with access to each device" - three N-channel and three P-channel
enhancement mode MOS transistors (but things are wired in a particular way;
you have to see the schematic in the datasheet to understand)
- 4069UB
- hex inverter (these can be
biased into a linear mode of operation; they're used in place of op amps
in the
EDP
Wasp filter)
"Vactrols"
There are a variety of vactrols, but the VTL5C3 is the "magic" one that
shows up in the Buchla designs.
Operational Transconductance Amplifiers (OTA)
Norton Amplifiers
"VCA" chips
Current in, current out, exponential voltage control:
Rumor has it that the
THAT chips may be
used in some of the newest STS Serge VCF designs; I'm not sure
where else they might be used.
The SSM2164 looks pretty nice (it's an updated variant of the SSM2024,
which appears all over place on the Oberheim OB-Mx schematic).
Four-Quadrant Multipliers
- Analog Devices AD 633 (computes
((X1-X2) * (Y1-Y2) / 10 V) + Z
- Fairchild RC4200 (current mode;
computes I3 = I1 * I2 / I4)
- On Semiconductor MC1496 Balanced
Modulator/Demodulator ($0.79/each Digikey)
Comparators
Comparator comparisons and notes by Jim Patchell (sdiy list, 1/1/06) (why
does "comparator" have an "a" and "comparisons" have an "i"?)
- LM319 (dual) - fast,
high performance voltage
comparators ($0.31/each Jameco)
- LM393 (dual),
LM339 (quad) - low performance
voltage comparator ($0.19/each Jameco)
- LM392 - interesting
combination of one LM339 type
comparitor and one LM324 type op amp
- LM311 - medium performance
single voltage comparator (takes more careful layout to prevent it from
oscillating than the LM393 and LM339; also has more flexible output)
Op Amps
- National Semiconductor
LM324 (quad) and
LM358 (dual) - bipolar,
can run off of a single supply (actually has problems in when used with
a dual supply; see Harry
Bissel's, Jim Patchell's, and Ian Fritz's posts),
good for control voltages, not so great for audio (Pat Kammerer recommends
the MC3403 instead; Mike ??? recommends the MC34074 - "like a supercharged
LM324")
-
Texas Instruments TL081/082/084 JFET-input
(giving high input impedance),
good for audio, in single/dual/quad versions
(made by other manufacturers as well) (TL081, $0.32/each Newark,
TL082, $0.38/25 Newark)
-
Motorola TL081/082/084 -
sometimes it's useful to have
datasheets from different manufacturers
-
National Semiconductor TL082 (strange, National
doesn't seem to make the 081 or 084)
-
Texas Instruments TL071/072/074 - lower
noise version of the TL08x (TL071, $0.32/each Newark; TL074 $0.25/each/25
Future Electronics, $0.38/each/25 Allied)
- National LF442 (dual) and
LF444 - favorites of
Ray Wilson;
maybe try them in place
of TL08x for lower power consumption (LF442 $0.79/each Allied; LF444
$1.17/each Allied)
- National Semiconductor ap notes:
- NE5532 dual,
NE5534
single - very high quality audio, although there's DC offset issues.
5534 has some "balance" pins not present on the 5532.
(NE5532 $0.65/each Allied,
NJM5532 $0.58/each Mouser
NE5534 $0.78/each Jameco, NJM5534 $0.35/each Mouser)
- CA3140 (single, $0.52/each at Allied),
CA3240 (dual, $1.05/each at Newark)
MOSFET input/bipolar output, insanely
high input impedances - often used in VCO integrators and in sample-and-holds
(Pat Kammerer says: "...very good for single supply applications,
partially due to the voltage swing that includes the - rail, and even a
bit more. I would replace a 741 with this in most cases, citing higher
bandwidth, and higher slew rate..." J. Haible says: "...makes a great
buffer in OTA-based phasers, as it's high impedance and doesn't suffer
from phase reversal as much as the usual BiFET amps.")
- CA3160 MOSFET input/CMOS output, capaple
of rail-to-rail output operation. Out of production; listed since it's used
in the Buchla 259 timbre circuitry. Frequency compensated version of CA3130.
- CA3130 - like CA3160, but uncompensated
- JRC4558
or NJM4558 (dual) bipolar, mediocre specs
from a modern viewpoint, but
potentially useful if you're trying to sound retro - remember these were
generally chosen because they were cheap, not because they were particularly
good!
- OP275
dual bifet, with "Butler amplifier front
end" - really high performance, good audio
and DC behavior (datasheet sounds like hype though - "sound quality of
JFETs?" what the heck is THAT supposed to mean?) ($1.93/each Allied)
- OPA134/2134/4134
(single/dual/quad) - also really high
performance (a favorite of Ian Fritz; he writes that they have
"super-low distortion (0.00008% for audio amplification, low input
bias current (5 pA) and voltage offset (0.5 mV) for integtrator
applications and fast slew rate (20V/us) for cap discahrage
usage. for lower offset I like the OPA2227.")
(OPA134 $2.25/each Newark, OPA2134 $2.37/each Newark)
- Misc. application notes:
- Op Amp Circuit Collection (AN-31)
- Audio Applications of Linear Integrated
Circuits (including "Exponential V-F Converter")
Electronic Switches
- DG211
quad CMOS switch (up to +/- 15 V signals)
- 4066 quad CMOS switch
(up to +/- 7.5 V signals)
Voltage Regulators
Suggested by Ian Fritz.
- National LM336-5 (5 volt),
LM336-2.5 (2.5 volt)
- National LM329 (6.9 volt)
- Fairchild TL431 Programmable Shunt
Regulator - can be set
to any value between 2.5 volts and 36 volts with two external resistors
Miscellaneous Interesting Chips
- LM398 sample and hold
- LM1894 Dynamic Noise Reduction System
(single-ended)
Voltage Controlled Oscillators (VCO)
With the exception of the XR4151, these don't actually seem to turn up in
synth schematics very often.
"Universal" Filters
These seem to be pretty expensive! I haven't seen any of them appear
in synth designs...