- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄384961 > TCM4400ETQFP (Texas Instruments, Inc.) GSM/DCS BASEBAND AND VOICE A/D AND D/A RF INTERFACE CIRCUIT PDF資料下載
參數(shù)資料
| 型號： | TCM4400ETQFP |
| 廠商： | Texas Instruments, Inc. |
| 英文描述： | GSM/DCS BASEBAND AND VOICE A/D AND D/A RF INTERFACE CIRCUIT |
| 中文描述： | 的GSM / DCS的基帶和語音的A / D和D / A射頻接口電路 |
| 文件頁數(shù)： | 40/64頁 |
| 文件大?。?/td> | 888K |
| 代理商： | TCM4400ETQFP |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁第35頁第36頁第37頁第38頁第39頁當(dāng)前第40頁第41頁第42頁第43頁第44頁第45頁第46頁第47頁第48頁第49頁第50頁第51頁第52頁第53頁第54頁第55頁第56頁第57頁第58頁第59頁第60頁第61頁第62頁第63頁第64頁
TCM4400E
GSM/DCS BASEBAND AND VOICE A/D
AND D/A RF INTERFACE CIRCUIT
SLWS082A – JULY 1999 – REVISED MARCH 2000
40
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
PRINCIPLES OF OPERATION
voltage references
Voltage and current generators are integrated inside the GSM converter. Some additional components are
required for the decoupling and regulation of the internal references. In addition, the internal buffers are
automatically shut down with the corresponding functions being powered down.
There are six terminals reserved for voltage references decoupling and use: VGAP, IBIAS, VREF, MICBIAS,
and VMID (see Table 1):
VGAP:
This terminal is connected to the internal band gap reference voltage. It must be externally
connected to a 0.1-
μ
F capacitor. The band gap drives the current generator and the voltage
reference. This bandgap may be powered down by the PWRDN pin, depending on bit VGAPPN
of register PWDNRG2.
IBIAS:
This terminal is connected to the current reference. It must be externally connected to a 100 k
resistor. As this block is connected to the AFC function, the power down is controlled with similar
means. The current generator is shut down with the same bits as the band gap – one bit for the
power down selection of a hardware solution (with the external PWRDN terminal).
VREF:
This terminal is connected to the internal reference voltage. It must be externally connected to a
0.1-
μ
F capacitor. This band gap may be powered down with the control of the bits VREFPN and
VREFPD of the register PWDNRG2. This voltage reference is internally connected to three
buffers corresponding to the blocks of speech downlink, speech uplink, and GMSK downlink. The
two first blocks are powered down with the inactivity of the corresponding speech blocks. This last
block is shut down outside the radio downlink activations.
VMID:
This buffer gives the V
DD
/2 or 1.35 V common-mode output voltage of the baseband uplink path.
This voltage value is selected with the SELVMID bit.
MICBIAS:
This buffer is designed to drive an electret-type microphone. The output voltage can be chosen
by software (bit MICBIAS of VBCTL1 register) between the value 2 V to 2.5 V.
ADCMID:
For decoupling purposes, the ADCMID terminal is connected to the internal comparison threshold
of the ADC. Setup time before the ADC is powered on is dependent on the value of the external
decoupling capacitor.
Table 1. Voltage References
REFERENCE
VOLTAGE
DEFINITION
VGAP
1.22 V
Band gap used for all other references
VREF
1.75 V
Voltage reference of GMSK internal ADC and DAC
VMID
AVDD2/2
2 V / 2.5 V
Common-mode reference for uplink/downlink GMSK
MICBIAS
Microphone-driving voltage
ADCMID
AVDD3/2
Voltage dc biasing of the auxiliary ADCs
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| tcm5003d | 1/4 Inch 330k Pixel Color Image Sensor(1/4英寸330k像素彩色圖象傳感器) |
| TCM5089 | TONE ENCODER |
| TCM5092 | TONE ENCOER |
| TCM5094 | TONE ENCOER |
| TCM50 | TONE ENCODER |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| TCM46T | 制造商:MINICIR 功能描述:New |
| TCM4910 | 制造商:TI 制造商全稱:Texas Instruments 功能描述:PCM U-LOW COMPANDING CODES |
| TCM4949VPA | 制造商:ON Semiconductor 功能描述: |
| TCM50 | 制造商:TI 制造商全稱:Texas Instruments 功能描述:TONE ENCODER |
| TCM5087 | 制造商:TI 制造商全稱:Texas Instruments 功能描述:TONE ENCODER |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。