参数资料
型号: 5962-554901NXDR
厂商: TEXAS INSTRUMENTS INC
元件分类: 比较器
英文描述: DUAL COMPARATOR, 10000 uV OFFSET-MAX, 650 ns RESPONSE TIME, PDSO8
封装: SO-8
文件页数: 2/15页
文件大小: 238K
代理商: 5962-554901NXDR
TLC372, TLC372Q, TLC372Y
LinCMOS
DUAL DIFFERENTIAL COMPARATORS
SLCS114B – NOVEMBER 1983 – REVISED MARCH 1999
10
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
PRINCIPLES OF OPERATION
input protection circuit operation
Texas Instruments patented protection circuitry allows for both positive-and negative-going ESD transients.
These transients are characterized by extremely fast rise times and usually low energies, and can occur both
when the device has all pins open and when it is installed in a circuit.
positive ESD transients
Initial positive charged energy is shunted through Q1 to VSS. Q1 turns on when the voltage at the input rises
above the voltage on the VDD pin by a value equal to the VEB of Q1. The base current increases through R2
with input current as Q1 saturates. The base current through R2 forces the voltage at the drain and gate of Q2
to exceed its threshold level (VT ~ 22 V to 26 V) and turn Q2 on. The shunted input current through Q1 to VSS
is now shunted through the n-channel enhancement-type MOSFET Q2 to VSS. If the voltage on the input pin
continues to rise, the breakdown voltage of the zener diode D3 is exceeded, and all remaining energy is
dissipated in R1 and D3. The breakdown voltage of D3 is designed to be 24 to 27 V, which is well below the gate
oxide voltage of the circuit to be protected.
negative ESD transients
The negative charged ESD transients are shunted directly through D1. Additional energy is dissipated in R1
and D2 as D2 becomes forward biased. The voltage seen by the protected circuit is – 0.3 V to – 1 V (the forward
voltage of D1 and D2).
circuit-design considerations
LinCMOS
products are being used in actual circuit environments that have input voltages that exceed the
recommended common-mode input voltage range and activate the input protection circuit. Even under normal
operation, these conditions occur during circuit power up or power down, and in many cases, when the device
is being used for a signal conditioning function. The input voltages can exceed VICR and not damage the device
only if the inputs are current limited. The recommended current limit shown on most product data sheets is
±5 mA. Figures 5 and 6 show typical characteristics for input voltage versus input current.
Normal operation and correct output state can be expected even when the input voltage exceeds the positive
supply voltage. Again, the input current should be externally limited even though internal positive current limiting
is achieved in the input protection circuit by the action of Q1. When Q1 is on, it saturates and limits the current
to approximately 5-mA collector current by design. When saturated, Q1 base current increases with input
current. This base current is forced into the VDD pin and into the device IDD or the VDD supply through R2
producing the current limiting effects shown in Figure 5. This internal limiting lasts only as long as the input
voltage is below the VT of Q2.
When the input voltage exceeds the negative supply voltage, normal operation is affected and output voltage
states may not be correct. Also, the isolation between channels of multiple devices (duals and quads) can be
severely affected. External current limiting must be used since this current is directly shunted by D1 and D2 and
no internal limiting is achieved. If normal output voltage states are required, an external input voltage clamp is
required (see Figure 7).
相关PDF资料
PDF描述
5962-751401QHA DUAL OP-AMP, 2500 uV OFFSET-MAX, 0.046 MHz BAND WIDTH, CDFP10
5962-8760401GA OP-AMP, 3000 uV OFFSET-MAX, MBCY8
5962-8760601GX BUFFER AMPLIFIER, MBCY8
5962-8760601CX BUFFER AMPLIFIER, CDIP14
5962-8760601CA BUFFER AMPLIFIER, CDIP14
相关代理商/技术参数
参数描述
596256-000 制造商:TE Connectivity 功能描述:LM-1-TAPE-CR 制造商:TE Connectivity 功能描述:LM-1-TAPE-CR - Cable Rools/Shrink Tubing
5962-7602001VDA 制造商:Texas Instruments 功能描述:NAND Gate 4-Element 2-IN Bipolar 14-Pin CFPAK Tube
5962-7603901VFA 制造商:Texas Instruments 功能描述:Monostable Multivibrator Dual 16-Pin CFPAK Tube
5962-7700401EA 制造商:Texas Instruments 功能描述:Demultiplexer/Decoder, 2 To 4 Line, 16 Pin, Ceramic, DIP
5962-77008012A 制造商:Rochester Electronics LLC 功能描述:- Bulk