ZHCSH81 December 2017 PGA302
PRODUCTION DATA.
PGA302 allows for Open Wire Diagnostics to be performed in the ECU. Specifically, the ECU can detect open VDD or Open GND wire by installing a pullup or pulldown on VOUT line.
Fault No. | Device VDD | Device GND | Device VOUT | Remark | Device status after removal of failure |
---|---|---|---|---|---|
1 | 5 V | 0 V | Pullup to VDD | Normal Connection with VOUT to Pulled to VDD | Resumes normal operation |
2 | 5 V | 0 V | Pulldown to GND | Normal Connection with VOUT to Pulled to GND | Device Reset |
3 | 20 V | 0 V | GND to VDD | Overvoltage | Device Reset |
4 | Open | 0 V | Pullup to VDD = 5 V | Open VDD with VOUT Pulled to VDD | Device Reset |
5 | Open | 0 V | Pulldown to GND | Open VDD with VOUT Pulled to GND | Device Reset |
6 | 5 V | Open | Pullup to VDD = 5 V | Open GND with VOUT Pulled to VDD | Device Reset |
7 | 5 V | Open | Pulldown to GND | Open GND with VOUT Pulled to GND | Device Reset |
8 | 0 V | 20 V | Pullup to VDD | Reverse Voltage with VOUT Pulled to VDD | Device Reset |
9 | 0 V | 20 V | Pulldown to GND | Reverse Voltage with VOUT Puledl to GND | Physical Damage possible. |
10 | 0 V | 0 V | Pullup to VDD | VDD Shorted to GND with VOUT Pulled to VDD | Device Reset |
11 | 0 V | 0 V | Pulldown to GND | VDD Shorted to GND with VOUT Pulled to GND | Device Reset |
12 | 20 V | 20 V | Pullup to VDD | GND Shorted to VDD with VOUT Pulled to VDD | Device Reset. Physical Damage possible. |
13 | 20 V | 20 V | Pulldown to GND | GND Shorted to VDD with VOUT Pulled to GND | Device Reset |
14 | 20 V | 0 V | 20 V | VOUT Shorted to VDD | Device Reset. Physical Damage possible. |
15 | 20 V | 0 V | 0 V | VOUT Shorted to GND | Resumes normal operation |
Figure 32 shows the possible harness open wire faults on VDD and GND pins.
Table 9 summarizes the open wire diagnostics and the corresponding resistor pull values that allows the ECU to detect open harness faults.
Open Harness | ECU Pull Direction | Max Pull Value (KΩ) | State of PGA302 during fault condition | ECU Voltage Level (VOUT/OWI pin) |
---|---|---|---|---|
VDD | Pullup | 50 | PGA302 is off. Leakage currents present (especially at high temp) | VDD – (Ileak1 × Rpullup) |
GND | Pullup | N/A | PGA302 is off, all power rails pulled up to VDD | VDD |
VDD | Pulldown | N/A | PGA302 is off, all power rails pulled down to ground | GND |
GND | Pulldown | 50 | PGA302 is off, leakage current pushed into VOUT pin (thru the chip's ground). | GND + (Ileak2 × Rpulldown) |