ZHCSE24B April 2015 – April 2019 AM3358-EP
PRODUCTION DATA.
The touch screen controller (TSC) and analog-to-digital converter (ADC) subsystem (TSC_ADC) is an 8-channel general-purpose ADC with optional support for interleaving TSC conversions for 4-wire, 5-wire, or 8-wire resistive panels. The TSC_ADC subsystem can be configured for use in one of the following applications:
Table 5-12 summarizes the TSC_ADC subsystem electrical parameters.
PARAMETER | TEST CONDITIONS | MIN | NOM | MAX | UNIT |
---|---|---|---|---|---|
Analog Input | |||||
VREFP(1) | (0.5 × VDDA_ADC) + 0.25 | VDDA_ADC | V | ||
VREFN(1) | 0 | (0.5 × VDDA_ADC) – 0.25 | V | ||
VREFP + VREFN(1) | VDDA_ADC | V | |||
Full-scale input range | Internal voltage reference | 0 | VDDA_ADC | V | |
External voltage reference | VREFN | VREFP | |||
Differential nonlinearity (DNL) | Internal voltage reference:
VDDA_ADC = 1.8 V External voltage reference: VREFP – VREFN = 1.8 V |
–1 | 0.5 | 1 | LSB |
Integral nonlinearity (INL) | Source impedance = 50 Ω
Internal voltage reference: VDDA_ADC = 1.8 V External voltage reference: VREFP – VREFN = 1.8 V |
–2 | ±1 | 2 | LSB |
Source impedance = 1 kΩ
Internal voltage reference: VDDA_ADC = 1.8 V External voltage reference: VREFP – VREFN = 1.8 V |
±1 | ||||
Gain error | Internal voltage reference:
VDDA_ADC = 1.8 V External voltage reference: VREFP – VREFN = 1.8 V |
±2 | LSB | ||
Offset error | Internal voltage reference:
VDDA_ADC = 1.8 V External voltage reference: VREFP – VREFN = 1.8 V |
±2 | LSB | ||
Input sampling capacitance | 5.5 | pF | |||
Signal-to-noise ratio (SNR) | Internal voltage reference:
VDDA_ADC = 1.8 V External voltage reference: VREFP – VREFN = 1.8 V Input signal: 30-kHz sine wave at –0.5-dB full scale |
70 | dB | ||
Total harmonic distortion (THD) | Internal voltage reference:
VDDA_ADC = 1.8 V External voltage reference: VREFP – VREFN = 1.8 V Input signal: 30-kHz sine wave at –0.5-dB full scale |
75 | dB | ||
Spurious free dynamic range | Internal voltage reference:
VDDA_ADC = 1.8 V External voltage reference: VREFP – VREFN = 1.8 V Input signal: 30-kHz sine wave at –0.5-dB full scale |
80 | dB | ||
Signal-to-noise plus distortion | Internal voltage reference:
VDDA_ADC = 1.8 V External voltage reference: VREFP – VREFN = 1.8 V Input signal: 30-kHz sine wave at –0.5-dB full scale |
69 | dB | ||
VREFP and VREFN input impedance | 20 | kΩ | |||
Input impedance of AIN[7:0](2) | ƒ = Input frequency | [1 / ((65.97 × 10–12) × ƒ)] | Ω | ||
Sampling Dynamics | |||||
ADC clock frequency | 3 | MHz | |||
Conversion time | 13 | ADC clock cycles | |||
Acquisition time | 2 | 257 | ADC clock cycles | ||
Sampling rate | ADC clock = 3 MHz | 200 | kSPS | ||
Channel-to-channel isolation | 100 | dB | |||
Touch Screen Switch Drivers | |||||
Pullup and pulldown switch ON resistance (Ron) | 2 | Ω | |||
Pullup and pulldown switch current leakage Ileak | Source impedance = 500 Ω | 0.5 | uA | ||
Drive current | 25 | mA | |||
Touch screen resistance | 6 | kΩ | |||
Pen touch detect | 2 | kΩ |