CD4029B中文资料CMOS 可预置加/减计数器数据手册TI规格书

描述 Description

CD4029B consists of a four-stage binary or BCD-decade up/down counter with provisions for look-ahead carry in both counting modes. The inputs consist of a single CLOCK, CARRY-IN\\ (CLOCK ENABLE\\), BINARY/DECADE, UP/DOWN, PRESET ENABLE, and four individual JAN signals, Q1, Q2, Q3, Q4 and a CARRY OUT\\ signal are provided as outputs.

A high PRESET ENABLE signal allows information on the JAM INPUTS to preset the counter to any state asynchronously with the clock. A low on each JAM line, when the PRESET-ENABLE signal is high, resets the counter to its zero count. The counter is advanced one count at the positive transition of the clock when the CARRY-IN\\ and PRESET ENALBE signals are low. Advancement is inhibited when the CARRY-IN\\ or PRESET ENABLE signals are high. The CARRY-OUT\\ signal is normally high and goes low when the counter reaches its maximum count in the UP mode or the minimum count in the DOWN mode provided the CARRY-IN\\ signal is low. The CARRY-IN\\ signal in the low state can thus be considered a CLOCK ENABLE\\. The CARRY-IN\\ terminal must be connected to VSS when not in use.

Binary counting is accomplished when the BINARY/DECADE input is high; the counter counts in the decade mode when the BINARY/DECADE input is low. The counter counts up when the UP/DOWN input is high, and down when the UP/DOWN input is low. Multiple packages can be connected in either a parallel-clocking or a ripple-clocking arrangement as shown in Fig. 17.

Parallel clocking provides synchronous control and hence faster response from all counting outputs. Ripple-clocking allows for longer clock input rise and fall times.

The CD4029B-series types are supplied in 16-lead hermetic dual-in-line ceramic packages (F3A suffix), 16-lead dual-in-line plastic packages (E suffix), 16-lead small-outline packages (M, M96, MT and NSR suffixes), and 16-lead thin shrink small-outline packages (PW and PWR suffixes).

特性 Features

• Medium-speed operation… 8 MHz (typ.) @ CL = 50 pF and VDD–VSS = 10 V
• \"Preset Enable\" and individual \"Jam\" inputs provided
• BCD outputs in decade mode
• 5-V, 10-V, and 15-V parametric ratings
• Maximum input current of 1 µA at 18 V over full package-temperature range; 100 nA at 18 V and 25°C
• Meets all requirements of JEDEC Tentative Standard No. 13B, \"Standard Specifications for Description of ’B’ Series CMOS Devices\"
• Programmable binary and decade counting/frequency synthesizers-BCD output
• Up/Down binary counting
• Up/Down decade counting
• Difference counting