Specifications

C8051F330/1
58 Rev. 1.1
Table 7.1. Voltage Reference Electrical Characteristics
VDD = 3.0 V; -40°C TO +85°C UNLESS OTHERWISE SPECIFIED
PARAMETER CONDITIONS MIN TYP MAX UNITS
INTERNAL REFERENCE (REFBE = 1)
Output Voltage 25°C ambient 2.38 2.44 2.50 V
VREF Short-Circuit Current 10 mA
VREF Temperature Coefficient 15 ppm/°C
Load Regulation Load = 0 to 200 µA to AGND 0.5 ppm/µA
VREF Turn-on Time 1 4.7µF tantalum, 0.1µF ceramic bypass 2 ms
VREF Turn-on Time 2 0.1µF ceramic bypass 20 µs
VREF Turn-on Time 3 no bypass cap 10 µs
Power Supply Rejection 140 ppm/V
EXTERNAL REFERENCE (REFBE = 0)
Input Voltage Range 0 VDD V
Input Current Sample Rate = 200 ksps; VREF = 3.0 V 12 µA
BIAS GENERATORS
ADC Bias Generator BIASE = ‘1’ 100 µA
Reference Bias Generator 40 µA
Figure 7.2. REF0CN: Reference Control Register
Bits7-4: UNUSED. Read = 0000b; Write = don’t care.
Bit3: REFSL: Voltage Reference Select.
This bit selects the source for the internal voltage reference.
0: VREF pin used as voltage reference.
1: VDD used as voltage reference.
Bit2: TEMPE: Temperature Sensor Enable Bit.
0: Internal Temperature Sensor off.
1: Internal Temperature Sensor on.
Bit1: BIASE: Internal Analog Bias Generator Enable Bit.
0: Internal Bias Generator off.
1: Internal Bias Generator on.
Bit0: REFBE: Internal Reference Buffer Enable Bit.
0: Internal Reference Buffer disabled.
1: Internal Reference Buffer enabled. Internal voltage reference driven on the VREF pin.
R R R R R/W R/W R/W R/W Reset Value
- - - - REFSL TEMPE BIASE REFBE 00000000
Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0 SFR Address:
0xD1