WM8310GEB/V Wolfson Microelectronics, WM8310GEB/V Datasheet - Page 279

• Manufacturer Part Number: WM8310GEB/V
• Description: POWER MANAGEMENT SUBSYSTEM, 169BGA
• Manufacturer: Wolfson Microelectronics

Specifications of WM8310GEB/V

• Supply Voltage: 7V
• No. Of Step-down Dc - Dc Converters: 4
• No. Of Ldo Regulators: 11
• Digital Ic Case Style: BGA
• No. Of Pins: 169
• No. Of Regulated Outputs: 13
• Operating Temperature Range: -40°C To
• Rohs Compliant: Yes
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Pre-Production
30.6 BATTERY TEMPERATURE MONITORING COMPONENTS
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Battery temperature monitoring is performed using a reference voltage output on the NTCBIAS pin. A
potential divider is formed between the NTC bias resistor and the NTC thermistor component within
the battery pack. The voltage present at the NTCMON pin is used to determine the battery
temperature. The recommended connections and the derivation of V
Figure 37 Battery Temperature Monitoring
The voltage thresholds for the Hot/Cold Battery Temperature conditions are fixed in the WM8310:
If the NTC thermistor has a nominal resistance of 100kΩ at 25°C, and follows the Vishay Resistance-
Temperature Curve 1, then the above equations result in the Hot Battery threshold = 40°C and the
Cold Battery threshold = 0°C.
For example, if the NTC thermistor resistance is 53.4kΩ at 40°C, then V
following equation:
The upper and lower temperature thresholds can be adjusted by modification of the NTC bias
resistor and/or the addition of another resistor between the battery pack and the NTCMON pin.
If only the NTC bias resistor is adjusted, then either the upper or lower threshold can be selected, but
not both; the other threshold will be determined by the thermistor characteristics.
If an additional resistor is inserted between the battery pack and the NTCMON pin, then the upper
and lower thresholds can be independently selected, with the constraint that the upper and lower
thresholds must be at least 40°C apart.
The Cold Battery condition is detected when V
The Hot Battery condition is detected when V
NTCMON
NTCMON
< 0.348 x V
> 0.765 x V
NTCMON
PP, December 2009, Rev 3.0
NTCBIAS
is shown in Figure 37.
NTCBIAS
NTCMON
is given by the
WM8310
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