| Autor: |
Yeonjung Lee, Ohjo Kwon, Sanghyun Cha, Kichang Jang, Sangduk Yu, Kyougsoo Kwon, Joongho Choi |
| Rok vydání: |
2008 |
| Předmět: |
|
| Zdroj: |
ISCAS |
| DOI: |
10.1109/iscas.2008.4541865 |
| Popis: |
The analog front end (AFE) chip is presented to perform precise automatic focus operations with a piezoelectric actuator for mobile phone camera applications. In order to achieve the desired frequency response of a piezoelectric actuator, the frequency of a multi-vibrator oscillator can be swept in various manners such as the frequency step and the number of transitions between frequency changes. A novel method using the resistor ladder circuit is incorporated for a bridge-driving signal generator whose frequency can be linearly swept and controlled according to the input digital code. The AFE chip is implemented in a 0.35-mum 1-poly 4-metal CMOS technology and runs at the single supply voltage of 2.8 V. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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