TL5501

6-BIT ANALOG-TO-DIGITAL CONVERTER

SLAS026 – OCTOBER 1989 – REVISED APRIL 1990

2

POST OFFICE BOX 655303

equivalents of analog input circuit

ANLG VCC

VI

D

ri

VrefB

(see Note A)

Ci

Ibias

ANLG GND

ANLG VCC

VI

NOTE A: Ci – nonlinear emitter-follower junction capacitance

ri – linear resistance model for input current transition caused by comparator switching.

VI < VrefB: Infinite; CLK high: infinite.

VrefB – voltage at REFB terminal

Ibias – constant input bias current

D – base-collector junction diode of emitter-follower transistor

equivalent of digital input circuit

Vref = 1.4 V

Output

25 k

Ω

3.1 k

Ω

25 k

Ω

GND

VI

DGTL VCC