THS1230 Datasheet, PDF (6/22 Pages) Texas Instruments – 3.3-V, 12-BIT, 30 MSPS, LOW-POWER ANALOG-TO-DIGITAL CONVERTER WITH POWER DOWN

THS1230
SLAS291B – OCTOBER 2000 – REVISED MARCH 2004
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ELECTRICAL CHARACTERISTICS (CONTINUED)
over recommended operating conditions (AV_DD = DV_DD = 3.3 V, f_s = 30 MHz/50% duty cycle, MODE = 1, 1-V input span,
internal reference, T_min to T_max) (unless otherwise noted)
REFT, REFB REFERENCE VOLTAGES (all supplies = 3.3 V)
INTERNAL REFERENCE⁽¹⁾
PARAMETER
TEST CONDITION
MIN TYP MAX UNIT
V_REFT Upper reference voltage
V_REFB Lower reference voltage
V_REF Differential reference voltage, V_REFT – V_REFB
Differential reference voltage, V_REFT – V_REFB accuracy
EXTERNAL REFERENCE
2.15
1.15
V
0.95
1 1.05
–5%
5%
Externally applied V_REFT reference voltage range
Externally applied V_REFB reference voltage range
Externally applied (V_REFT – V_REFB) reference voltage range
External mode V_REFT to V_REFB impedance
INTERNAL OR EXTERNAL REFERENCE
2
2.5
1.05
1.3 V
0.75
1.05
9
kΩ
C_T
V_REFT decoupling capacitor value
C_B
V_REFB decoupling capacitor value
C_TB
Decoupling capacitor V_REFT to V_REFB
0.1
0.1
µF
10
(1) The internal reference voltage is not intended for use driving off chip.
THS1230
1.5 V
BAND
GAP
REFT
CT
CTB
Figure 1. Reference Generation
REFB
CB
6