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I decided to start this wiki to keep track of all info we can find about how to improve the E-MU 0404 USB (and possibly the Tracker Pre) sound interfaces.
[top]Component identification and function
The contents of this section should be to identify on-board components and their function.
[top]Observations
- opamps U16, U33, and U39 get Vcc &= 6.14V and Vdd &= -6.46V. Probably the other opamps get the same input voltage.
- Vdd on these opamps has nasty high frequency ripple of about 6mV p-p
- Vcc measures about 2mV p-p
- pin 5 of the TPS6755 supplies the negative voltage Vdd, and has the exact shape ripple seen on the opamp Vdd; interesting that the TPS7655 works
at a switching frequency of 160kHz and the ripple frequency seems right about that. If anything, this would be where I'd start, by replacing the Vdd supply.
[top]Power converters
PHKI = TPS62200DBV IC
high efficiency sot23 step-down dc-dc converter, 2.5V-6V input,
adjustable output 0.7V to 6V, 1MHz PWM
data sheet http://focus.ti.com/lit/ds/symlink/tps62200.pdf
part ID: U42
nearby: R310 code 66D is 475K, R313 code 90C is 84.5K
Vout &= 0.5 * (1 + R310/R313) &= 3.31V
part ID: U23
nearby: R207 code 26D is 182K, R208 code 66D is 475K
Vout &= 0.5 * (1 + R208/R207) &= 1.82V
PHOI = TPS61040DBV IC
low-power sot23 dc-dc boost converter
1.8V-6V input, adjustable output voltage up to 28V
up to 1MHz switching frequency
up to 400mA
data sheet http://focus.ti.com/lit/ds/slvs413e/slvs413e.pdf
part ID: U10
nearby: R99 code 39B is 2K49, R97 code 94C is 93K1
Vout &= 1.233 * (1 + R97/R99) &= 47.33V
is this the 48V phantom power???, when the TPS61040 is rated to give only up to 28V?
PGVI = TPS73001DBVR IC
low-noise, high psrr, RF 200-mA low-dropout adjustable linear regulator
Vin up to 6V, adjustable output voltage 1.22V-5.5V
PSRR 68dB at 1kHz, line regulation 0.05 %/V, load regulation 5mV (delta Vout % / delta Iout, up to 200mA), output noise voltage 23uVrms (tps73018) from 200Hz to 100kHz
data sheet http://www.datasheetcatalog.org/data...5r0y9xf33y.pdf
part ID: U35
nearby R283 code 94C 93K1, R300 code 47C 30K1
Vout &= 1.225 * (1 + R283/R300) &= 5.01V
part ID: U25
nearby R225 code 94C 93K1, R230 code 47C 30K1
Vout &= 1.225 * (1 + R225/R230) &= 5.01V
S28B = LM2704 IC
micropower step-up dc-dc conveter with 550mA peak current limit
2.2V-7V input voltage, up to 20V adjustable output voltage
datasheet: http://www.national.com/profile/snip.cgi/openDS=LM2704
part ID: U43
nearby R312 code 01D is 100K, R314 code 243 is 24K
Vout &= 1.237 * (1 + R312/R314) &= 6.39V
what is this for? 2 possibilies are the LEDs and the opamps themselves?
6755I = TPS6755I IC
adjustable invertind dc-dc converter
input voltage 2.7V-9V, output voltage limited to Vout &<= 12V - Vin
160kHz fixed-frequency PWM controller
data sheet http://www.datasheetcatalog.org/data...p4ygdksqwy.pdf
part ID: U28
I think this supplies -5V
15532 IC = NE5532 (?) IC
part ID: U1, U2, many others
http://www.datasheetcatalog.org/data...ild/NE5532.pdf
internally compensated for gain 1
slew rate 8V/uS, en 8nV/sqrtHz, GB 10MHz, Vo 5mV
possible replacement AD8599, en 1nV/sqrtHz, Vo 10uV, GB 10MHz, slew rate 16V/uS, thd -105dB or 0.00000056
data sheet http://www.datasheetcatalog.org/data...ild/NE5532.pdf
note: in the e-mu 0404 usb these opamps seem to get 12.6V on pins 4-8; where from?
2068 IC &= JRC2068 = NJM2068 IC
part ID: many
unity gain bandwidth
THD 0.001%
slew rate 6V/uS
data sheet http://futuretrek.elektroda.eu/Elementy/JRC2068.pdf
note: in the e-mu 0404 usb these seem to get 12.6V on pins 4-8, where from?
[top]Unidentified
[top]Mod categories
[top]Power supply
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