Electronic Components Datasheet Search |
|
MAX1242BCPA Datasheet(PDF) 8 Page - Maxim Integrated Products |
|
MAX1242BCPA Datasheet(HTML) 8 Page - Maxim Integrated Products |
8 / 12 page +2.7V to +5.25V, Low-Power, 10-Bit Serial ADCs in SO-8 8 _______________________________________________________________________________________ Serial Interface Initialization after Power-Up and Starting a Conversion When power is first applied, and if SHDN is not pulled low, it takes the fully discharged 4.7µF reference bypass capacitor up to 20ms to provide adequate charge for specified accuracy. With an external refer- ence, the internal reset time is 10µs after the power supplies have stabilized. No conversions should be performed during these times. To start a conversion, pull CS low. At CS’s falling edge, the T/H enters its hold mode and a conversion is initiat- ed. After an internally timed conversion period, the end of conversion is signaled by DOUT pulling high. Data can then be shifted out serially with the external clock. Using S SH HD DN N to Reduce Supply Current Power consumption can be reduced significantly by shutting down the MAX1242/MAX1243 between con- versions. Figure 6 shows a plot of average supply cur- rent vs. conversion rate. Because the MAX1243 uses an external reference voltage (assumed to be present continuously), it “wakes up” from shutdown more quick- ly, providing lower average supply currents. The wake- up time, tWAKE, is the time from SHDN deasserted to the time when a conversion may be initiated (Figure 5). For the MAX1242, this time depends on the time in shutdown (Figure 7) because the external 4.7µF refer- ence bypass capacitor loses charge slowly during shutdown. The MAX1243’s wake-up time is largely dependent on the external reference’s power-up time. If the external reference is not shut down, the wake-up time is approximately 4µs. 10,000 100 1000 1 0.1 1 10 100 1k 10k 100k 10 CONVERSIONS/SEC VDD = VREF RLOAD = ∞, CLOAD = 50pF CODE = 0101010100 MAX1242 VDD = 3V MAX1242 VDD = 5V MAX1243 VDD = 3V Figure 6. Average Supply Current vs. Conversion Rate 1.0 0.0 0.001 0.01 0.1 1 10 0.8 0.6 0.4 0.2 TIME IN SHUTDOWN (sec) Figure 7. Typical Reference-Buffer Power-Up Delay vs. Time in Shutdown COMPLETE CONVERSION SEQUENCE tWAKE POWERED UP POWERED DOWN POWERED UP CONVERSION 0 CONVERSION 1 DOUT CS SHDN Figure 5. Shutdown Sequence |
Similar Part No. - MAX1242BCPA |
|
Similar Description - MAX1242BCPA |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.NET |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |