Rainbow Electronics MAX9034 - Manual (Page 6)

MAX9030/MAX9031/MAX9032/MAX9034
Detailed Description
The MAX9030/MAX9031/MAX9032/MAX9034 are sin-
gle/dual/quad low-cost comparators. They have an
operating supply voltage from +2.5V to +5.5V when
operating from a single supply and from ±1.25V to
±2.75V when operating from dual power supplies, and
consume only 35µA. Their common-mode input voltage
range extends from the negative supply to within 1.1V
of the positive supply. Internal hysteresis ensures clean
output switching, even with slow-moving input signals.
Shutdown Mode
The MAX9030 comparator comes with a power-saving
shutdown mode. When in shutdown, the supply current
drops from a typical 35µA to 0.05µA, and the outputs
become high impedance. SHDN has a high input imped-
ance and typically draws 0.1µA when connected to V
SS
or V DD . A maximum logic low voltage of 0.3V ✕ V DD
applied to SHDN places the device in the shutdown
mode. A minimum logic high voltage of 0.7V
✕ V DD
applied to SHDN will enable normal operation. To dis-
able shutdown, connect SHDN to V
DD .
Applications Information
Adding Hysteresis
Hysteresis extends the comparator’s noise margin by
increasing the upper threshold and decreasing the
lower threshold. A voltage-divider from the output of the
comparator sets the trip voltage. Therefore, the trip volt-
age is related to the output voltage.
These comparators have 4mV internal hysteresis.
Additional hysteresis can be generated with two resis-
tors using positive feedback (Figure 1). Use the follow-
ing procedure to calculate resistor values:
Low-Cost, Ultra-Small, Single/Dual/Quad
Single-Supply Comparators
6 _______________________________________________________________________________________
Pin Description
PIN
M A X9 0 3 0 M A X9 0 3 1 M A X9 0 3 2 M A X9 0 3 4
NAME FUNCTION
1 1 — — IN+ Comparator Noninverting Input
2 2 4 11 V SS N eg ati ve S up p l y V ol tag e. Byp ass w i th a 0.1µF cap aci tor .
3 3 — — IN- Comparator Inverting Input
4 4 — — OUT Comparator Output
5 — — — SHDN Shutdown
6 5 8 4 V DD P osi ti ve S up p l y V ol tag e. Byp ass w i th a 0.1µF cap aci tor .
— — 1 1 OUTA Comparator A Output
— — 2 2 INA- Comparator A Inverting Input
— — 3 3 INA+ Comparator A Noninverting Input
— — 5 5 INB+ Comparator B Noninverting Input
— — 6 6 INB- Comparator B Inverting Input
— — 7 7 OUTB Comparator B Output
— — — 8 OUTC Comparator C Output
— — — 9 INC- Comparator C Inverting Input
— — — 10 INC+ Comparator C Noninverting Input
— — — 12 IND+ Comparator D Noninverting Input
— — — 13 IND- Comparator D Inverting Input
— — — 14 OUTD Comparator D Output