Acutechnology Semiconductor Inc.
BQ8211
Application Notes
1. Typical Application
Notes:
1. Output voltage is 1.175V * (R1 +R2)/R2
2. Input and output capacitors should be located close to the device.
3. The BQ8211 will remain stable with C2 and C3 as low as 1.0
µF.
Overall transient performance is improved with increased capacitance.
4. The output is fully enabled when Enable is above 1V. EN may be driven by either a digital
or analog signal to control turn-on time.
2. Stability
A
Vin
Capacitor is also recommended. A 1µF capacitor is a bypassing for almost all applications.
A larger capacitor is also suitable depending on the cleanliness of the V
IN
source.
The
Output
capacitor is critical in maintaining regular stability. The BQ8211 is stable with an
output capacitor greater than 1µF. Any increase of the output capacitor will merely improve
the loop stability and the load transient response.
Tantalum Capacitors exhibit the best stability over a wide range of loads and are recommended.
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Rev. 1.3 September 13, 2006