HTOP01

www.honeywell.com

4

SYMBOL

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

Digital Input Low Voltage

Applies to XCLK, SEL, SHDN pins

0.1

0.3

Volts

Supply Current w/SHDN

asserted

SHDN=1

150

A

Notes

(1) As temperature increases, current into the op amp inputs becomes dominated by leakage current from the input protect

diodes. At 250 C junction temperature, diode leakage current can reach

100nA when the input level is near VDD or VSS. Net

leakage current drops significantly as the input level approaches mid-rail, and is at a minimum when the input level is precisely

midway between VDD and VSS.

Additionally, the diode structures on each input are well matched to each other, and will exhibit nearly identical leakage current

behavior. Consequently, offset current IOS between the two inputs is typically about 1% of the IB level. Thus, if the input level is

maintained near mid-rail, IOS is very low (<|1nA|), even at 250 C junction temperature.

(2) Output drive current capability is related to output swing magnitude. The HTOP01 will sink and source 20mA minimum over

temperature with the output swinging to within 300mV of either rail. At lesser loads, the output can swing closer to the supply rails;

at loads of 1mA, the output will reach to within 10mV of either rail. For applications where the output remains 500mV away from

the rails, up to 40mA output current is available. Current limiting activates when output current exceeds approximately 50mA.

(3) Supply current consumed by each op amp is PTAT (Proportional To Absolute Temperature) in nature, and as the name

suggests increases proportional to temperature. The 5.0mA maximum current given in the table reflects the maximum current

consumed at 250 C junction temperature by both amplifiers. At 25 C junction temperature, supply current is typically 2mA. PTAT

biasing maintains a near-constant amplifier bandwidth over temperature, a desirable characteristic.

(4) The HTOP01 is designed to handle

50mA output current per amplifier continuously over temperature, with no reduction in

rated product life. In the event of an overload condition, current limiting activates and limits output current to

50mA nominally.

However, due to fabrication process variations, the current limiting threshold can vary up to

30%. Consequently, it is possible to

have a current limiting threshold as high as

65mA. In this situation, if the overload (65mA) is allowed to continue indefinitely at

225 C ambient, there can be a reduction in rated product life. For maximum product life, it is recommended that any overload

output current situation (>50mA) be attended to promptly.

(5) The pseudo-random amplifier auto-zero clock is derived from an on-chip oscillator running at a nominal frequency of 4.0MHz.

(6) With SEL=0 the HTOP01 uses an internally generated clock for offset compensation. Setting SEL=1 and using an external

clock provides superior offset performance over the internal clock. The recommended frequency range for an external clock is

from 4KHz to 100KHz. Optimum performance is achieved with an external clock frequency of approximately 30KHz.

TYPICAL PERFORMANCE PLOTS

Noise Voltage Density vs. Frequency

External Clock = 3kHz

0

100

200

300

400

500

600

700

800

1 Hz

10 Hz

100 Hz

1000 Hz

10000 Hz

Frequency (Hz)

-55C Average

23C Average

225C Average

No clock 23C