数据搜索系统,热门电子元器件搜索 |
|
ADR280 数据表(PDF) 6 Page - Analog Devices |
|
ADR280 数据表(HTML) 6 Page - Analog Devices |
6 / 8 page ADR280 –6– ADR280 –7– Negative Reference A negative reference can be precisely configured without using any expensive tight tolerance resistors, as shown in Figure 10. The voltage difference between VOUT and V– is 1.2 V. Since VOUT is at virtual ground, U2 will close the loop by forcing the V– pin to be the negative reference output. V+ VOUT 0.1F V– ADR280 U1 +5V V+ V– –2.7V AD8541 –1.2V –VREF U2 C1 Figure 10. Negative Reference Boosted Reference with Scalable Output A precision user defined output with boosted current capabil- ity can be implemented with the circuit shown in Figure 11. In this circuit, U2 forces VO to be equal to VREF (1 + R2/R1) by regulating the turn-on of M1; the load current is therefore fur- nished by the 5 V supply. For higher output voltage, U2 must be changed and the supply voltage of M1 and U2 must also be elevated and separated from the U1 input voltage. In this config- uration, a 100 mA load is achievable at a 5 V supply.The higher the supply voltage, the lower the current handling is because of the heat generated on the MOSFET. For heavy capacitive loads, additional buffering is needed at the output to enhance the transient response. V+ VOUT V– ADR280 U1 5V V+ V– U2 R1 R2 RL 25 VO 10.8k 0.1% 10k 0.1% C2 1pF 1.2V AD8541 0.1F C1 M1 2.5V/100mA M1 = FDB301N, 2N7000, 2N7002, OR EQUIVALENT Figure 11. 2.5 V Boosted Reference GSM and 3G Mobile Station Applications The ADR280 voltage reference is ideal for use with analog base- band ICs in GSM and 3G mobile station applications. Figure 12 illustrates the use of the ADR280 with the AD6535 GSM analog baseband.The AD6535 provides all of the data converters and power management functions needed to implement a GSM mobile station, including baseband and audio codecs, voltage regulators, and a battery charger. Besides low current consump- tion and a small footprint, the ADR280 is optimized for excellent power supply rejection ratio (PSRR) necessary for optimum AD6535 device performance when the main battery voltage fluctuates during RF power amplifier activity. DIGITAL BASEBAND AD6535 ANALOG BASEBAND BASEBAND CODEC AUDIO CODEC POWER MANAGEMENT RADIO ADR280 VOLTAGE REFERENCE Figure 12. GSM Mobile Station Application REV. A REV. A |
类似零件编号 - ADR280 |
|
类似说明 - ADR280 |
|
|
链接网址 |
隐私政策 |
ALLDATASHEETCN.COM |
ALLDATASHEET是否为您带来帮助? [ DONATE ] |
关于 Alldatasheet | 广告服务 | 联系我们 | 隐私政策 | 链接交换 | 制造商名单 All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |