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- Newsgroups: comp.sys.palmtops
- Subject: Re: More Info on A/D Converters for the HP95
- Message-ID: <112160050@hpfcso.FC.HP.COM>
- From: rrd@hpfcso.FC.HP.COM (Ray Depew)
- Date: Fri, 13 Nov 1992 20:50:07 GMT
- References: <112160047@hpfcso.FC.HP.COM>
- Organization: Hewlett-Packard, Fort Collins, CO, USA
- Lines: 116
-
- Also edited from the original. See the end for additional comments.
- -- rrd 921113
-
- -------------------------------------------------------------------
- > Hi Ray-
- >
- > Thanks for the review. I was hoping you would supply some of the more
- > interesting specs like maximum sample rate, conversion time, and
- > sample & hold specifics (impedance, sample time, anti-aliasing
- > filters, etc.). Perhaps these specs are not available in the manual
- > (if they aren't they should be!).
-
- Can do. From the manual, here is the "Specifications" section, followed
- by other miscellaneous stuff culled from the pages:
-
- ============================================================================
- SPECIFICATIONS
-
- Analog Inputs
- -------------
- Input Configuration: MOSFET Input Op-Amp Follower
-
- Input Impedance: 1 Megohm for Vin from -.6 to 5.7 volts,
- otherwise 100K ohms
-
- Input Range: 0 to 5.1 volts (0 to 255), 30V maximum
-
- Resolution/Accuracy: 8 bits, 0.4% accuracy +/- .5 LSB
-
- Digital Inputs
- --------------
- Input Configuration: 74HCT Schmidt Trigger with 100K pullup
-
- Logic High Level: TTL/CMOS compatible; 2.0 volts minimum
-
- Logic Low Level: TTL/CMOS compatible; 0.8 volts maximum
-
- Input Current High: 0 uA maximum (floating inputs are high)
-
- Input Current Low: 50 uA (100K pullup)
-
- Maximum Input level: 30 VDC maximum
-
- Digital Outputs
- ---------------
- Output Configuration: Open drain MOSFET to common
-
- Output Resistance: 1 ohm maximum
-
- Output current: .5 amps continuous maximum
-
- Output Voltage: 30 volts maximum in off state
- .5 volts maximum in on state
-
- Power
- -----
- Battery Type: 9V, NEDA 1604 (alkaline) [normal 9V thing - rrd]
-
- Battery Life: 60 hours minimum, continuous operation
- 2000 hours typical in standby
-
- Current Drain: 6 mA maximum, .25 mA standby (PWM active)
-
- Physical/Environmental
- ----------------------
- Size: 3-1/4" width by 4-3/8" length by 1-1/2" height
-
- Weight: 6 ounces
-
- Connectors: Augat RDI 2SV Series- Lever Action-
- Wire sizes- #18 to #28 AWG
-
- Temperature Range: 0 to 55 degrees C (32 to 130 degrees F)
-
- ============================================================================
- MISCELLANEOUS OTHER INFORMATION
-
- Counter/Frequency Input
- -----------------------
- Maximum Frequency: 100 KHz max
-
- Maximum Count: 16,777,216 (24-bit counter)
-
- Sample Rate: 1 second (fixed)
-
- PWM Output
- ----------
- Frequency: 903.53 Hz
-
- Duty Cycle Range: 0 to 100%
-
- Duty Cycle Resolution: 0.4% or 1/255 (8-bit modulator)
-
- Burst mode analog input
- -----------------------
- Sample rate: 131 analog samples at .01 seconds per sample
-
- [No data given on normal mode analog input, but I suspect that it also has
- a S&H rate of 0.01 second. -- rrd]
-
- ======================================================================
-
- ADDITIONAL COMMENTS, 921113:
- ---------------------------
-
- The ADCM-48 was made to work with the 48, but there's no reason it couldn't
- work with the 95. There is, the small problem of software. The as-delivered
- HP95 cannot communicate directly with the ADCM. Anybody want to write a
- small program to do the job? If you are interested, contact John Wettroth
- at Travtech -- address and phone number given in my previous postings.
-
- --
- Regards
- Ray Depew
- Hewlett Packard Co, Fort Collins, Colorado
- rrd@hpfiqa.fc.hp.com
-