AD8280-EVALZ Analog Devices Inc, AD8280-EVALZ Datasheet
AD8280-EVALZ
Specifications of AD8280-EVALZ
Available stocks
Related parts for AD8280-EVALZ
AD8280-EVALZ Summary of contents
Page 1
... Each cell channel contains programmable deglitching circuitry to prevent alarms from transient input levels. The AD8280 also has two digital pins that can be used to select various combinations of inputs in the case where fewer than six cells are to be monitored. Most important, it has a self-test feature, ...
Page 2
... Threshold Inputs ........................................................................ 17 Top and Bottom Part Designation ........................................... 18 Typical Daisy-Chain Connections ........................................... 18 Shared or Separate Alarms ........................................................ 18 Deglitching Options ................................................................... 18 Enabling and Disabling the AD8280 ....................................... 20 Alarm Output ............................................................................. 20 Self-Test ....................................................................................... 20 Protection Components and Pull-Up/Pull-Down Resistors 23 EMI Considerations ................................................................... 23 System Accuracy Calculation ................................................... 23 ...
Page 3
... LDO source current ≤ 10.0 mA Seven settings: 0.0 sec, 0.1 sec, 0.8 sec, 1.6 sec, 3.2 sec, 6.4 sec, and 12.8 sec No capacitor on daisy chain From application enabled to LDO = 90% of value Rev Page AD8280 Min Typ Max Unit −25 +25 mV − ...
Page 4
... AD8280 Parameter Self-Test Completion Time Self-Test Valid Time, t STV Delay Time for Self-Test Start Delay Time for Data Valid Rise Time for Self-Test Pulse POWER SUPPLY Supply Voltage Range Quiescent Current Power Supply Enabled Power Supply Disabled Test Conditions/Comments Deglitch time = 0.0 sec Deglitch time > ...
Page 5
... V to LDO + 0.3 V Table 3. Thermal Resistance −0 VTOP + 0.3 V Package Type −0 LDO + 0.3 V −0 LDO + 0.3 V 48-Lead LQFP (ST-48) −0 LDO + 0.3 V −0 LDO + 0.3 V ESD CAUTION −0 VTOP + 0.3 V Rev Page AD8280 θ θ Unit °C/W ...
Page 6
... DGT2 Digital Select Pin 2. Used with DGT0 and DGT1 to select deglitch time (see Table 7). 25 AVOUTOT Alarm Voltage Output, Overtemperature. 26 AVOUTUV Alarm Voltage Output, Undervoltage. 27 AVOUTOV Alarm Voltage Output, Overvoltage PIN AD8280 Figure 2. Pin Configuration Rev Page VCC 35 GND1 34 GND2 33 NPTC ...
Page 7
... Alarm Current Input, Undervoltage. Used in daisy-chain configuration. 45 AIINOV Alarm Current Input, Overvoltage. Used in daisy-chain configuration. 46 TESTO Test Output. 47 BOT Used to identify part at lowest potential in daisy chain (see Table 6). 48 TOP Used to identify part at highest potential in daisy chain (see Table 6). Rev Page AD8280 ...
Page 8
... AD8280 TYPICAL PERFORMANCE CHARACTERISTICS SAMPLE SIZE = 2726 1800 1500 UNDERVOLTAGE OVERVOLTAGE 1200 900 600 300 0 –30 –20 –10 0 TRIP POINT ERROR (mV) Figure 3. Overvoltage and Undervoltage Trip Point Error, Voltage Between VIN0 and VIN1 1600 SAMPLE SIZE = 2726 UNDERVOLTAGE 1400 OVERVOLTAGE 1200 ...
Page 9
... Figure 14. Supply Current, Power-Down Mode Rev Page AD8280 4.9 5.0 5.1 5.2 5.3 LDO VOLTAGE (V) Figure 12. LDO Voltage 1.3 1.4 1.5 1.6 1.7 1.8 SUPPLY CURRENT (mA) Figure 13. Supply Current SAMPLE SIZE = 2726 – ...
Page 10
... AD8280 25 VOLTAGE BETWEEN VIN1 TO VIN2 AND VIN5 TO VIN6 –5 –10 –15 –20 –25 –50 –30 – TEMPERATURE (°C) Figure 15. Overvoltage Error vs. Temperature 25 VOLTAGE BETWEEN –5 –10 VIN2 TO VIN3 AND VIN3 TO VIN4 –15 –20 –25 –50 –30 – TEMPERATURE (°C) Figure 16. Undervoltage Error vs. Temperature ...
Page 11
... Figure 24. Supply Current vs. Stack Voltage (VIN6 – VIN0) STACK VOLTAGE = 7.5V STACK VOLTAGE = 18V STACK VOLTAGE = 29.8V –50 –30 – TEMPERATURE (°C) Figure 25. Enabled Supply Current vs. Temperature for Various Stack Voltages (VIN6 – VIN0) LDO REF SOURCE CURRENT (mA) Stack Voltage = 7.5 V AD8280 2.5 2.0 1.5 1.0 0 110 25 30 ...
Page 12
... AD8280 5.5 LDO 5.0 REF 4.5 4.0 3.5 3.0 2 SOURCE CURRENT (mA) Figure 27. LDO and Reference Voltage vs. LDO Source Current, Stack Voltage = 18 LDO REF 5 0 –50 –30 – TEMPERATURE (°C) Figure 28. LDO and Reference Source Current vs. Temperature 5.11 5.09 LDO 5.07 5.05 5 ...
Page 13
... Figure 35. TESTI and AVOUTxx, Deglitch Time = 0.0 sec, Self-Test Fails (UV TESTI 4 Figure 36. TESTI and AVOUTxx, Deglitch Time = 0.1 sec, Self-Test Passes TESTI 4 Figure 37. TESTI and AVOUTxx, Deglitch Time = 0.1 sec, Self-Test Fails (UV TESTI 2 Figure 38. TESTI Edge and AVOUTxx, Self-Test Fails (Enlarged) Rev Page AD8280 200ms/DIV 200ms/DIV 4µs/DIV ...
Page 14
... AD8280 TESTI 400ms/DIV Figure 39. Alarm Condition Entering Self-Test, Part Passes Self-Test TESTI 4µs/DIV Figure 40. Alarm Condition Entering Self-Test, Part Passes Self-Test (Enlarged) 1 ENBI OV 2 REF 3 TESTI 4 1ms/DIV Figure 41. Start-Up Time OV 1 CELL ALARM TRIPPED 2 Figure 42. Cell Voltage Change to Trip Alarm, Deglitch Time = 800 ms ...
Page 15
... THEORY OF OPERATION Figure 44 shows a block diagram of the AD8280. The AD8280 is a threshold monitor that can be used to monitor up to six cell voltages and two temperature voltages. The part can also be used in a daisy-chain configuration to monitor as many cells as required. The benefit of the daisy-chain configuration is that isolation is ...
Page 16
... REF pin and is better suited to drive the thermistor dividers voltage source other than that of the AD8280 LDO is used to drive the thermistor bridge (V VT1 and VT2 voltages be brought when the AD8280 is disabled or powered down because the VT1 and VT2 inputs must when the LDO is also 0.1µF ...
Page 17
... UV) with the reference, each divider should total no less than 50 kΩ. Rev Page VIN6 + VIN5 + VIN4 + VIN3 + VIN2 VIN1 VIN0 AD8280 Figure 48. Four-Cell Connections for the AD8280 VIN6 VIN5 VIN4 + VIN3 + VIN2 + VIN1 VIN0 AD8280 Figure 49. Three-Cell Connections for the AD8280 AD8280 ...
Page 18
... AIINUV, AIINOT, ENBO, and TESTO pins can be left floating, or they can be tied to VTOP. Standalone Part When the AD8280 is designated as a single part (used as a stand- alone part), the AIOUTOV, AIOUTUV, and AIOUTOT pins can be left floating, or they can be tied to part ground (VBOTx). ...
Page 19
... AIINxx ENBO VCCx LDOx REF/FB DGT0 DGT1 SEL0 AD8280 SEL1 BOT TOP ALRMSEL/ AVOUTxx DGT2/ NPTC TESTI AIOUTxx ENBI GNDx Figure 50. Typical Daisy-Chain Connections Rev Page AD8280 1.0µ REF REF REF 2.2µF 100nF REF REF REF REF REF REF ...
Page 20
... The AD8280 can be disabled or put into a standby mode by bringing the ENBI pin to logic low, lowering the quiescent current of the AD8280 from a maximum of 2 1.0 μA and dropping the LDO and reference output Bringing the ENBI pin to a logic high takes the part out of standby mode and enables it ...
Page 21
... Self-Test Timing and Monitoring Strategy When monitoring the signals for self-test on the AD8280, note the following items: • After initiating a self-test of the AD8280 with a rising edge on the TESTI pin, the alarm appearing at the AVOUTxx pin remains valid • When the rising edge of the TESTI pulse occurs, the user ...
Page 22
... AD8280 1 TESTI 0 1 AVOUTxx SELF-TEST PASS 0 1 AVOUTxx SELF-TEST FAIL TESTI 0 1 AVOUTxx SELF-TEST PASS 0 1 AVOUTxx t SELF-TEST FAIL RE 0 NOTES THE TIME FROM THE RISING EDGE OF THE TEST PULSE (TESTI) TO THE START OF THE SELF-TEST THE TIME FROM THE RISING EDGE OF THE TEST PULSE UNTIL THE PART COMPLETES ITS SELF-TEST (TEST PULSE MUST BE ...
Page 23
... Use ferrite beads on the VTOP lines as shown in Figure 50. • Use 100 nF capacitors across each of the six-cell battery stacks. • Place the AD8280 parts as close together as possible on the board to minimize the length of the daisy-chain lines. SYSTEM ACCURACY CALCULATION When calculating system accuracy, there are four error sources to consider: • ...
Page 24
... Model Temperature Range AD8280WASTZ −40°C to +105°C AD8280WASTZ-RL −40°C to +105°C AD8280-EVALZ RoHS Compliant Part Qualified for Automotive Applications. AUTOMOTIVE PRODUCTS The AD8280 models are available with controlled manufacturing to support the quality and reliability requirements of automotive applications. Note that these automotive models may have specifications that differ from the commercial models; therefore, designers should review the Specifications section of this data sheet carefully ...