TCM4400 Datasheet, PDF (17/72 Pages) Texas Instruments – GSM/DCS BASEBAND AND VOICE A/D AND D/A RF INTERFACE CIRCUIT

2.3.4 Baseband Uplink Path
PARAMETER
TEST CONDITIONS
MIN
TYP MAX UNIT
I and Q DAC resolution
8
bit
Dynamic range on each output
Centered on VVMID
VVREF
Vpp
Differential output dynamic range†
BULQP-BULQN or BULIP-BULIN
2 × VVREF
Vpp
Output load resistance, differential
10
kΩ
Output load capacitance, differential
50
pF
Output common-mode voltage
Programmable by bit SELVMID
VVMID
V
I and Q output state in power down
HiZ
† _{Initial values after reset and at beginning of each burst are BULIP–BULIN=VREF and BULQP–BULQN=0 corresponding}
to a phase angle of 0°.
2.3.5 dc Accuracy – Baseband Uplink Path
PARAMETER
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{Offset error before calibration}
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{Offset error after calibration}
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{Offset correction range}
MIN
– 90
–5
– 100
TYP MAX UNIT
0
90 mV
0
5 mV
0 100 mV
2.3.6 Dynamic Parameters – Baseband Uplink Path
PARAMETER
TEST CONDITIONS
MIN TYP MAX UNIT
Absolute gain error relative to VVREF Measured with 67.7-kHz sine wave
–1
0
1 dB
Maximum output random modulation
spectrum relative to in-band average
level. Measured by average fast Fourier
transforms (FFTs) of random bursts
using a flat top window‡ with 30-kHz
bandwidth.
100 kHz
200 kHz
250 kHz
400 kHz
600 kHz
– 3 dB
– 34 dB
– 37 dB
– 65 dB
– 72 dB
800 kHz
– 72 dB
‡ _{Flat top window is defined as: Dw(i)=D(i) × wf0 × (wf1 + wf2 × cos (2 × i ×} Π_{/n) + wf3 × cos ( 4 × i ×} Π_{/n)). With}
wf0=2.0660373, wf1 = 0.2810639, wf2 = – 0.5208972, wf3 = 0.1980399.
2.3.7 Smoothing Filters Characteristics – Baseband Uplink Path
PARAMETER
TEST CONDITIONS
MIN
Group delay
0 Hz to 100 kHz
TYP MAX UNIT
1.5
µs
2.3.8 I and Q Channels Gain and Phase Matching – Baseband Uplink Path
PARAMETER
TEST CONDITIONS
MIN TYP MAX
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{Gain matching between}
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ^channels
0 Hz to 96 kHz
Measured on 67.7 kHz sine wave
before calibration
Measured on 67.7 kHz sine wave
after calibration
–1
– 0.3
0
1
0 0.3
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Phase matching between
channels
0 Hz to 96 kHz
– 0.5°
0 0.5°
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{–0.15 0.0 0.15}
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{I and Q gain imbalance}
Programmable with bits IQSEL, ^{– 0.42 – 0.27 – 0.12}
G1, and G0
– 0.68 – 0.53 – 0.38
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ _{–0.93 –0.78 –0.63}
UNIT
dB
dB
2–3