A PNP-NPN output with common-base level shifting

L

Lauri Alanko

Guest
Hello.

Here is a circuit I came up with. It is meant to be a general-purpose
digital output stage: it takes in an inverted digital control signal
(typically low voltage and low current), and uses that to switch between
sourcing from a higher voltage and sinking to ground.

Out
Q1 | Q2
V+---v_/-------------+-----------\_^---Gnd
|Q3 D1 R1 R2 D2 |
\_^--\<|--\/\--+--\/\--\<|--+
| |
Vhi ~In

Q1 and Q2 do the switching between sourcing and sinking. I'm not sure
what the proper name for this configuration is. "Push-pull" seems to be
when NPN is on high side and PNP on low side, and "totem pole" seems to
refer to either that or to two NPNs on top of each other. But I haven't
seen this PNP-NPN configuration very much.

To me it seems it's much better to have PNP high and NPN low, since the
voltage drop is then much lower. Is this PNP-NPN switch in common use? If
so, what is it called? If not, what is the problem with it? The fact
that the transistors get saturated?

Q3 is an NPN in common-base configuration used to drive Q1 with a lower
voltage. Vhi is the high level of the input signal, so when input is
high, Q3 is at cutoff and so is Q1. When input is low, Q3 is active and
drives Q1 to saturation.

Do I need a pull-up resistor from the base of Q1 to V+? If so, why?
Is there some danger in leaving the base of Q1 floating when Q3 is at
cutoff?

The zener diodes D1 and D2 are there to prevent strike-through when
transitioning between high and low. They should drop about Vhi/2 to
ensure that one transistor won't activate before the other one has gone
into cutoff.

To me this seems like the simplest way of, say, driving a mosfet with a
microcontroller (using only cheap discrete parts). But I haven't seen
this particular circuit anywhere. Is it okay or is there a problem I have
overlooked?

Thanks in advance.


Lauri
 
On Tue, 3 Sep 2013 19:27:45 +0000 (UTC), Lauri Alanko <la@iki.fi>
wrote:

Hello.

Here is a circuit I came up with. It is meant to be a general-purpose
digital output stage: it takes in an inverted digital control signal
(typically low voltage and low current), and uses that to switch between
sourcing from a higher voltage and sinking to ground.

Out
Q1 | Q2
V+---v_/-------------+-----------\_^---Gnd
|Q3 D1 R1 R2 D2 |
\_^--\<|--\/\--+--\/\--\<|--+
| |
Vhi ~In

Q1 and Q2 do the switching between sourcing and sinking. I'm not sure
what the proper name for this configuration is. "Push-pull" seems to be
when NPN is on high side and PNP on low side, and "totem pole" seems to
refer to either that or to two NPNs on top of each other. But I haven't
seen this PNP-NPN configuration very much.

To me it seems it's much better to have PNP high and NPN low, since the
voltage drop is then much lower. Is this PNP-NPN switch in common use? If
so, what is it called? If not, what is the problem with it? The fact
that the transistors get saturated?

Q3 is an NPN in common-base configuration used to drive Q1 with a lower
voltage. Vhi is the high level of the input signal, so when input is
high, Q3 is at cutoff and so is Q1. When input is low, Q3 is active and
drives Q1 to saturation.

Do I need a pull-up resistor from the base of Q1 to V+? If so, why?
Is there some danger in leaving the base of Q1 floating when Q3 is at
cutoff?
Click to expand...

People tend to not like to leave bases open. A resistor would speed up
turnoff and increase the breakdown voltage of the PNP. BVcer > BVceo.
And reduce leakage, except that silicon transistors don't leak much.

The zener diodes D1 and D2 are there to prevent strike-through when
transitioning between high and low. They should drop about Vhi/2 to
ensure that one transistor won't activate before the other one has gone
into cutoff.

To me this seems like the simplest way of, say, driving a mosfet with a
microcontroller (using only cheap discrete parts). But I haven't seen
this particular circuit anywhere. Is it okay or is there a problem I have
overlooked?
Click to expand...

Looks OK. It is hard to find decent low-voltage zeners.

These are sort of cute:

https://dl.dropboxusercontent.com/u/53724080/Circuits/Power/TTL_to_HV.JPG

https://dl.dropboxusercontent.com/u/53724080/Circuits/Optos/Opto_Totem.JPG

https://dl.dropboxusercontent.com/u/53724080/Circuits/Optos/Faster_Opto_Totem.JPG



--

John Larkin Highland Technology, Inc

jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro acquisition and simulation
 
On Tue, 3 Sep 2013 19:27:45 +0000 (UTC), Lauri Alanko <la@iki.fi>
wrote:

Hello.

Here is a circuit I came up with. It is meant to be a general-purpose
digital output stage: it takes in an inverted digital control signal
(typically low voltage and low current), and uses that to switch between
sourcing from a higher voltage and sinking to ground.

Out
Q1 | Q2
V+---v_/-------------+-----------\_^---Gnd
|Q3 D1 R1 R2 D2 |
\_^--\<|--\/\--+--\/\--\<|--+
| |
Vhi ~In

Q1 and Q2 do the switching between sourcing and sinking. I'm not sure
what the proper name for this configuration is. "Push-pull" seems to be
when NPN is on high side and PNP on low side, and "totem pole" seems to
refer to either that or to two NPNs on top of each other. But I haven't
seen this PNP-NPN configuration very much.

To me it seems it's much better to have PNP high and NPN low, since the
voltage drop is then much lower. Is this PNP-NPN switch in common use? If
so, what is it called? If not, what is the problem with it? The fact
that the transistors get saturated?

Q3 is an NPN in common-base configuration used to drive Q1 with a lower
voltage. Vhi is the high level of the input signal, so when input is
high, Q3 is at cutoff and so is Q1. When input is low, Q3 is active and
drives Q1 to saturation.

Do I need a pull-up resistor from the base of Q1 to V+? If so, why?
Is there some danger in leaving the base of Q1 floating when Q3 is at
cutoff?

The zener diodes D1 and D2 are there to prevent strike-through when
transitioning between high and low. They should drop about Vhi/2 to
ensure that one transistor won't activate before the other one has gone
into cutoff.

To me this seems like the simplest way of, say, driving a mosfet with a
microcontroller (using only cheap discrete parts).
Click to expand...

Or buy a logic-level mosfet!


--

John Larkin Highland Technology, Inc

jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro acquisition and simulation
 
In article <dmlc299jkv2q46t26h34v3gv0dmu2amff8@4ax.com>,
Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:
Lose all but Q1 and Q2 and turn Q1 into a PMOS and Q2 into an NMOS and
you have a classic CMOS inverter.
Click to expand...

Indeed. I forgot to say that I have seen this configuration with
mosfets, but not with bjts. Here is an explicit example:

http://www.ti.com/lit/ml/slup169/slup169.pdf

On page 12 there is a normal non-inverting bipolar push-pull driver
(NPN-PNP), and on the next page there is a mosfet variant, which is
otherwise the same except it's inverting. There is no explanation why
the bipolar variant couldn't be inverting as well!

> What you have there in bipolar will not be particularly fast.

Because the transistors get saturated? The slower switching is the
price for less conduction loss (compared to standard push-pull)? I
don't think I'm going to need frequencies beyond, say, 50 kHz, so this
probably won't be an issue.

> What do you have in mind for the "low voltage" section, 5V?

Probably, since I'll mostly be using cheapo TTL ICs. Of course if I
use a microcontroller I could go as low as 1.8 V...

On Tue, 03 Sep 2013 14:30:39 -0700, John Larkin
jlarkin@highlandtechnology.com> wrote:

People tend to not like to leave bases open. A resistor would speed up
turnoff and increase the breakdown voltage of the PNP. BVcer > BVceo.
And reduce leakage, except that silicon transistors don't leak much.
Click to expand...

The turnoff speed is probably the only relevant issue here. Thanks.

> >Looks OK. It is hard to find decent low-voltage zeners.

Is this really a problem? Once you go beyond 2.4 V (the minimum for
zeners, I gather), can't you just stack p-n diodes (and maybe a
Schottky) to get the desired voltage drop?

These are sort of cute:

https://dl.dropboxusercontent.com/u/53724080/Circuits/Power/TTL_to_HV.JPG
Click to expand...

Too high voltage drops to my taste.

> >https://dl.dropboxusercontent.com/u/53724080/Circuits/Optos/Faster_Opto_Totem.JPG

This is quite pretty. Useless for me, but still.

> Or buy a logic-level mosfet!

That wouldn't solve the issue of driving a p-channel at high side.
Besides, it is my understanding that a mosfet's gate requires not only
voltage, but also a large momentary current (larger than control
devices can supply) in order to minimize the switching time and the
losses incurred during it. If this is true, then it seems that a
driver circuit would still be required even if gate voltage wasn't an
issue.


Lauri
 
On Tue, 03 Sep 2013 14:30:39 -0700, John Larkin
<jlarkin@highlandtechnology.com> wrote:

On Tue, 3 Sep 2013 19:27:45 +0000 (UTC), Lauri Alanko <la@iki.fi
wrote:

Hello.

Here is a circuit I came up with. It is meant to be a general-purpose
digital output stage: it takes in an inverted digital control signal
(typically low voltage and low current), and uses that to switch between
sourcing from a higher voltage and sinking to ground.

Out
Q1 | Q2
V+---v_/-------------+-----------\_^---Gnd
|Q3 D1 R1 R2 D2 |
\_^--\<|--\/\--+--\/\--\<|--+
| |
Vhi ~In
Click to expand...

Lose all but Q1 and Q2 and turn Q1 into a PMOS and Q2 into an NMOS and
you have a classic CMOS inverter.

What you have there in bipolar will not be particularly fast.

What do you have in mind for the "low voltage" section, 5V?

Larkin's "TTL_to_HV.JPG" is the same as my MC1554 output stage (yet
another coffee bet with Tom Frederiksen :) But is not particularly
fast on the upstroke. The MC1554 was designed for audio.

Q1 and Q2 do the switching between sourcing and sinking. I'm not sure
what the proper name for this configuration is. "Push-pull" seems to be
when NPN is on high side and PNP on low side, and "totem pole" seems to
refer to either that or to two NPNs on top of each other. But I haven't
seen this PNP-NPN configuration very much.

To me it seems it's much better to have PNP high and NPN low, since the
voltage drop is then much lower. Is this PNP-NPN switch in common use? If
so, what is it called? If not, what is the problem with it? The fact
that the transistors get saturated?

Q3 is an NPN in common-base configuration used to drive Q1 with a lower
voltage. Vhi is the high level of the input signal, so when input is
high, Q3 is at cutoff and so is Q1. When input is low, Q3 is active and
drives Q1 to saturation.

Do I need a pull-up resistor from the base of Q1 to V+? If so, why?
Is there some danger in leaving the base of Q1 floating when Q3 is at
cutoff?

People tend to not like to leave bases open. A resistor would speed up
turnoff and increase the breakdown voltage of the PNP. BVcer > BVceo.
And reduce leakage, except that silicon transistors don't leak much.


The zener diodes D1 and D2 are there to prevent strike-through when
transitioning between high and low. They should drop about Vhi/2 to
ensure that one transistor won't activate before the other one has gone
into cutoff.

To me this seems like the simplest way of, say, driving a mosfet with a
microcontroller (using only cheap discrete parts). But I haven't seen
this particular circuit anywhere. Is it okay or is there a problem I have
overlooked?

Looks OK. It is hard to find decent low-voltage zeners.

These are sort of cute:

https://dl.dropboxusercontent.com/u/53724080/Circuits/Power/TTL_to_HV.JPG
Click to expand...

Sort of looks like my MC1554 output stage from the '60's...

http://www.analog-innovations.com/SED/MC1554-DataSheet.pdf

https://dl.dropboxusercontent.com/u/53724080/Circuits/Optos/Opto_Totem.JPG

https://dl.dropboxusercontent.com/u/53724080/Circuits/Optos/Faster_Opto_Totem.JPG
Click to expand...

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.
 
On Tue, 03 Sep 2013 19:27:45 +0000, Lauri Alanko wrote:

Hello.

Here is a circuit I came up with. It is meant to be a general-purpose
digital output stage: it takes in an inverted digital control signal
(typically low voltage and low current), and uses that to switch between
sourcing from a higher voltage and sinking to ground.

Out
Q1 | Q2
V+---v_/-------------+-----------\_^---Gnd
|Q3 D1 R1 R2 D2 | \_^--\<|--\/\--+--\/\--\<|--+
| |
Vhi ~In

Q1 and Q2 do the switching between sourcing and sinking. I'm not sure
what the proper name for this configuration is. "Push-pull" seems to be
when NPN is on high side and PNP on low side, and "totem pole" seems to
refer to either that or to two NPNs on top of each other. But I haven't
seen this PNP-NPN configuration very much.

To me it seems it's much better to have PNP high and NPN low, since the
voltage drop is then much lower. Is this PNP-NPN switch in common use?
If so, what is it called? If not, what is the problem with it? The fact
that the transistors get saturated?

Q3 is an NPN in common-base configuration used to drive Q1 with a lower
voltage. Vhi is the high level of the input signal, so when input is
high, Q3 is at cutoff and so is Q1. When input is low, Q3 is active and
drives Q1 to saturation.

Do I need a pull-up resistor from the base of Q1 to V+? If so, why?
Is there some danger in leaving the base of Q1 floating when Q3 is at
cutoff?

The zener diodes D1 and D2 are there to prevent strike-through when
transitioning between high and low. They should drop about Vhi/2 to
ensure that one transistor won't activate before the other one has gone
into cutoff.

To me this seems like the simplest way of, say, driving a mosfet with a
microcontroller (using only cheap discrete parts). But I haven't seen
this particular circuit anywhere. Is it okay or is there a problem I
have overlooked?

Thanks in advance.
Click to expand...

Any time you connect a PNP to an NPN collector to collector there's a
risk of turning both transistors on at the same time. Shoot-through can
get ugly.

For low-power design, just slap a tiny-logic buffer on the board. For
high power -- I dunno, maybe it'll work, but as mentioned there are speed
issues.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
 
[snip all]

Here's a version of a gate driver using NPN and PNP transistors that will
drive a large MOSFET with a gate resistor of 2 ohms and an extra 3800 pF
gate capacitance, with less than 100 nSec rise and fall times (according to
LTSpice). The constant current stage of Q4, D1, D2, R4, and R7 can be
replaced with just a 5k resistor at the expense of switching time, although
you can probably use a lower value that would just draw higher current. The
constant current stage allows this to be used on a variety of voltages with
similar performance. For low frequency switching it can be made quite
efficient by changing the current.

Paul

===================================================================================Version 4
SHEET 1 1172 680
WIRE -32 -144 -32 -160
WIRE -32 -144 -192 -144
WIRE 112 -144 -32 -144
WIRE 144 -144 112 -144
WIRE 224 -144 144 -144
WIRE 384 -144 224 -144
WIRE 768 -144 384 -144
WIRE 912 -144 768 -144
WIRE 896 -64 768 -64
WIRE 912 -64 896 -64
WIRE 112 -48 112 -144
WIRE 384 -48 384 -144
WIRE 160 -16 144 -16
WIRE 896 -16 896 -64
WIRE 960 -16 896 -16
WIRE -192 0 -192 -144
WIRE 768 0 768 -64
WIRE 832 0 768 0
WIRE -32 16 -32 -144
WIRE 224 32 224 0
WIRE 224 64 224 32
WIRE 320 64 320 0
WIRE 320 64 224 64
WIRE 384 80 384 48
WIRE 480 80 384 80
WIRE 512 80 480 80
WIRE 640 80 640 -16
WIRE 640 80 592 80
WIRE 656 80 640 80
WIRE 720 80 656 80
WIRE 224 112 224 64
WIRE 384 112 384 80
WIRE 960 144 960 48
WIRE 1024 144 960 144
WIRE 1056 144 1024 144
WIRE -80 160 -112 160
WIRE 0 160 -80 160
WIRE 112 160 112 32
WIRE 112 160 80 160
WIRE 160 160 112 160
WIRE 320 160 320 64
WIRE 656 160 656 80
WIRE 1056 176 1056 144
WIRE 144 224 144 -16
WIRE -192 304 -192 80
WIRE -112 304 -112 240
WIRE -112 304 -192 304
WIRE -32 304 -32 80
WIRE -32 304 -112 304
WIRE 144 304 -32 304
WIRE 224 304 224 208
WIRE 224 304 144 304
WIRE 384 304 384 208
WIRE 384 304 224 304
WIRE 656 304 656 224
WIRE 656 304 384 304
WIRE 768 304 768 96
WIRE 768 304 656 304
WIRE 960 304 960 208
WIRE 960 304 768 304
WIRE 1056 304 1056 256
WIRE 1056 304 960 304
WIRE 224 320 224 304
FLAG 224 320 0
FLAG 832 0 Vsw
FLAG 640 -16 Vg
FLAG -80 160 Vin
FLAG 480 80 Vdrv
FLAG 1024 144 Vout
SYMBOL voltage -112 144 R0
WINDOW 0 37 59 Left 2
WINDOW 3 -109 182 Left 2
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value PULSE(0 5 10u 10n 10n 2u 10u 1000)
SYMBOL npn 160 112 R0
SYMATTR InstName Q1
SYMATTR Value 2N3904
SYMBOL pnp 320 208 M180
WINDOW 0 49 26 Left 2
WINDOW 3 38 52 Left 2
SYMATTR InstName Q2
SYMATTR Value 2N4403
SYMBOL res 96 144 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R1
SYMATTR Value 200
SYMBOL res 128 48 R180
WINDOW 0 36 76 Left 2
WINDOW 3 36 40 Left 2
SYMATTR InstName R2
SYMATTR Value 4.99k
SYMBOL res 240 -48 R180
WINDOW 0 36 76 Left 2
WINDOW 3 36 40 Left 2
SYMATTR InstName R4
SYMATTR Value 27
SYMBOL res 496 96 R270
WINDOW 0 32 56 VTop 2
WINDOW 3 0 56 VBottom 2
SYMATTR InstName R5
SYMATTR Value 10
SYMBOL voltage -192 -16 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V2
SYMATTR Value 15
SYMBOL nmos 720 0 R0
SYMATTR InstName M1
SYMATTR Value STB120NF10
SYMBOL res 752 -160 R0
SYMATTR InstName R6
SYMATTR Value 100k
SYMBOL npn 320 -48 R0
SYMATTR InstName Q3
SYMATTR Value 2N3904
SYMBOL ind 896 -160 R0
SYMATTR InstName L1
SYMATTR Value 10u
SYMATTR SpiceLine Ipk=10 Rser=0.0172 Rpar=32450 Cpar=5.52p mfg="Wurth
Elektronik" pn="7445710 WE-PD4 XL"
SYMBOL schottky 944 -16 R0
SYMATTR InstName D3
SYMATTR Value MBRS360
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL polcap 944 144 R0
WINDOW 3 24 64 Left 2
SYMATTR Value .47u
SYMATTR InstName C1
SYMATTR Description Capacitor
SYMATTR Type cap
SYMATTR SpiceLine V=50 Irms=210m Rser=0.45 MTBF=1000 Lser=0 ppPkg=1
SYMBOL res 1040 160 R0
SYMATTR InstName R3
SYMATTR Value 50
SYMBOL cap -48 16 R0
SYMATTR InstName C2
SYMATTR Value 1u
SYMBOL cap 640 160 R0
SYMATTR InstName C3
SYMATTR Value 3800p
SYMBOL pnp 160 32 M180
WINDOW 0 49 26 Left 2
WINDOW 3 38 52 Left 2
SYMATTR InstName Q4
SYMATTR Value 2N4403
SYMBOL res 160 320 R180
WINDOW 0 36 76 Left 2
WINDOW 3 36 40 Left 2
SYMATTR InstName R7
SYMATTR Value 1k
SYMBOL diode 128 -80 R0
SYMATTR InstName D1
SYMATTR Value 1N4148
SYMBOL diode 128 -144 R0
SYMATTR InstName D2
SYMATTR Value 1N4148
TEXT -224 504 Left 2 !.tran 200u startup
 
On Tue, 03 Sep 2013 14:47:08 -0700, Jim Thompson
<To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:

On Tue, 03 Sep 2013 14:30:39 -0700, John Larkin
jlarkin@highlandtechnology.com> wrote:

On Tue, 3 Sep 2013 19:27:45 +0000 (UTC), Lauri Alanko <la@iki.fi
wrote:

Hello.

Here is a circuit I came up with. It is meant to be a general-purpose
digital output stage: it takes in an inverted digital control signal
(typically low voltage and low current), and uses that to switch between
sourcing from a higher voltage and sinking to ground.

Out
Q1 | Q2
V+---v_/-------------+-----------\_^---Gnd
|Q3 D1 R1 R2 D2 |
\_^--\<|--\/\--+--\/\--\<|--+
| |
Vhi ~In

Lose all but Q1 and Q2 and turn Q1 into a PMOS and Q2 into an NMOS and
you have a classic CMOS inverter.

What you have there in bipolar will not be particularly fast.

What do you have in mind for the "low voltage" section, 5V?

Larkin's "TTL_to_HV.JPG" is the same as my MC1554 output stage (yet
another coffee bet with Tom Frederiksen :) But is not particularly
fast on the upstroke. The MC1554 was designed for audio.


Q1 and Q2 do the switching between sourcing and sinking. I'm not sure
what the proper name for this configuration is. "Push-pull" seems to be
when NPN is on high side and PNP on low side, and "totem pole" seems to
refer to either that or to two NPNs on top of each other. But I haven't
seen this PNP-NPN configuration very much.

To me it seems it's much better to have PNP high and NPN low, since the
voltage drop is then much lower. Is this PNP-NPN switch in common use? If
so, what is it called? If not, what is the problem with it? The fact
that the transistors get saturated?

Q3 is an NPN in common-base configuration used to drive Q1 with a lower
voltage. Vhi is the high level of the input signal, so when input is
high, Q3 is at cutoff and so is Q1. When input is low, Q3 is active and
drives Q1 to saturation.

Do I need a pull-up resistor from the base of Q1 to V+? If so, why?
Is there some danger in leaving the base of Q1 floating when Q3 is at
cutoff?

People tend to not like to leave bases open. A resistor would speed up
turnoff and increase the breakdown voltage of the PNP. BVcer > BVceo.
And reduce leakage, except that silicon transistors don't leak much.


The zener diodes D1 and D2 are there to prevent strike-through when
transitioning between high and low. They should drop about Vhi/2 to
ensure that one transistor won't activate before the other one has gone
into cutoff.

To me this seems like the simplest way of, say, driving a mosfet with a
microcontroller (using only cheap discrete parts). But I haven't seen
this particular circuit anywhere. Is it okay or is there a problem I have
overlooked?

Looks OK. It is hard to find decent low-voltage zeners.

These are sort of cute:

https://dl.dropboxusercontent.com/u/53724080/Circuits/Power/TTL_to_HV.JPG

Sort of looks like my MC1554 output stage from the '60's...

http://www.analog-innovations.com/SED/MC1554-DataSheet.pdf


https://dl.dropboxusercontent.com/u/53724080/Circuits/Optos/Opto_Totem.JPG

https://dl.dropboxusercontent.com/u/53724080/Circuits/Optos/Faster_Opto_Totem.JPG
Click to expand...

<http://www.analog-innovations.com/SED/PhotoCoupler-Fast.pdf>


...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.
 
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